[Federal Register Volume 89, Number 98 (Monday, May 20, 2024)]
[Rules and Regulations]
[Pages 43986-44049]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-08543]



[[Page 43985]]

Vol. 89

Monday,

No. 98

May 20, 2024

Part II





Department of Energy





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10 CFR Parts 429 and 431





Energy Conservation Program: Test Procedure for Air-Cooled, 
Evaporatively-Cooled, and Water-Cooled Commercial Package Air 
Conditioners and Heat Pumps; Final Rule

  Federal Register / Vol. 89, No. 98 / Monday, May 20, 2024 / Rules and 
Regulations  

[[Page 43986]]


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DEPARTMENT OF ENERGY

10 CFR Parts 429 and 431

[EERE-2023-BT-TP-0014]
RIN 1904-AD93


Energy Conservation Program: Test Procedure for Air-Cooled, 
Evaporatively-Cooled, and Water-Cooled Commercial Package Air 
Conditioners and Heat Pumps

AGENCY: Office of Energy Efficiency and Renewable Energy, Department of 
Energy.

ACTION: Final rule.

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SUMMARY: The U.S. Department of Energy (``DOE'') is amending the 
Federal test procedures for air-cooled commercial package air 
conditioners and heat pumps with a rated cooling capacity greater than 
or equal to 65,000 Btu/h, evaporatively-cooled commercial package air 
conditioners, and water-cooled commercial package air conditioners to 
incorporate by reference the latest versions of the applicable industry 
test standards. Specifically, DOE is amending the current test 
procedure for this equipment for measuring the current cooling and 
heating metrics--integrated energy efficiency ratio (``IEER'') and 
coefficient of performance (``COP''), respectively; and establishing a 
new test procedure for this equipment that adopts two new metrics--
integrated ventilation, economizer, and cooling (``IVEC'') and 
integrated ventilation and heating efficiency (``IVHE''). Testing to 
the IVEC and IVHE metrics will not be required until such time as 
compliance is required with any amended energy conservation standard 
based on the new metrics. Additionally, DOE is amending certain 
provisions of DOE's regulations related to representations and 
enforcement for the subject equipment.

DATES: The effective date of this rule is August 5, 2024. The 
amendments will be mandatory for testing the subject equipment starting 
May 15, 2025.
    The incorporation by reference of certain material listed in this 
rule is approved by the Director of the Federal Register on August 5, 
2024. The incorporation by reference of certain other materials listed 
in this rule were approved by the Director of the Federal Register as 
of January 22, 2016.

ADDRESSES: The docket, which includes Federal Register notices, public 
meeting webinar attendee lists and transcripts, comments, and other 
supporting documents/materials, is available for review at 
www.regulations.gov under docket number EERE-2023-BT-TP-0014. All 
documents in the docket are listed in the www.regulations.gov index. 
However, not all documents listed in the index may be publicly 
available, such as those containing information that is exempt from 
public disclosure.
    A link to the docket web page can be found at www.regulations.gov/docket/EERE-2023-BT-TP-0014. The docket web page contains instructions 
on how to access all documents, including public comments, in the 
docket.
    For further information on how to review the docket, contact the 
Appliance and Equipment Standards Program staff at (202) 287-1445 or by 
email: [email protected].

FOR FURTHER INFORMATION CONTACT: Mr. Troy Watson, U.S. Department of 
Energy, Office of Energy Efficiency and Renewable Energy, Building 
Technologies Office, EE-5B, 1000 Independence Avenue SW, Washington, DC 
20585-0121. Telephone: (240) 449-9387. Email: 
[email protected].
    Mr. Eric Stas, U.S. Department of Energy, Office of the General 
Counsel, GC-33, 1000 Independence Avenue SW, Washington, DC 20585-0121. 
Telephone: (202) 586-4798. Email: [email protected].
    For further information on how to review the docket, contact the 
Appliance and Equipment Standards Program staff at (202) 287-1445 or by 
email: [email protected].

SUPPLEMENTARY INFORMATION: DOE maintains a previously approved 
incorporation by reference and incorporates by reference the following 
industry standards into parts 429 and 431:
    AHRI Standard 340/360-2022 (I-P), 2022 Standard for Performance 
Rating of Commercial and Industrial Unitary Air-conditioning and Heat 
Pump Equipment, AHRI-approved January 26, 2022 (``AHRI 340/360-2022'').
    AHRI Standard 1340-2023 (I-P), 2023 Standard for Performance Rating 
of Commercial and Industrial Unitary Air-conditioning and Heat Pump 
Equipment, AHRI-approved November 16, 2023 (``AHRI 1340-2023'').
    Copies of AHRI 340/360-2022 and AHRI 1340-2023 can be obtained from 
the Air-Conditioning, Heating, and Refrigeration Institute (``AHRI''), 
2311 Wilson Blvd., Suite 400, Arlington, VA 22201, (703) 524-8800, or 
online at: www.ahrinet.org/standards/search-standards.
    ANSI/ASHRAE Standard 37-2009, Methods of Testing for Rating 
Electrically Driven Unitary Air-Conditioning and Heat Pump Equipment, 
ASHRAE-approved June 24, 2009 (``ANSI/ASHRAE 37-2009'').
    Copies of ANSI/ASHRAE 37-2009 can be obtained from the American 
Society of Heating, Refrigerating and Air-Conditioning Engineers 
(``ASHRAE''), 180 Technology Parkway NW, Peachtree Corners, GA 30092, 
(404) 636-8400, or online at: www.ashrae.org.
    See section IV.N of this document for a further discussion of these 
standards.

Table of Contents

I. Synopsis of the Final Rule
II. Authority and Background
    A. Authority
    B. Background
III. Discussion
    A. Scope of Applicability
    B. Definitions
    1. CUAC and CUHP Definition
    2. Basic Model Definition
    3. Double-Duct Definition
    4. Metric Definitions
    C. Updates to Industry Standards
    1. AHRI 340/360
    2. AHRI 1340
    3. ASHRAE 37
    D. Term Sheet Recommendations and Metrics
    1. IVEC
    2. IVHE
    E. DOE Adopted Test Procedures and Comments Received
    1. Overall
    2. Double-Duct Systems
    3. ECUACs and WCUACs
    a. Overall
    b. ESP Requirements for ECUACs and WCUACs
    c. ECUAC and WCUAC Test Temperatures and WCUAC Heat Rejection 
Components
    4. IVHE for Colder Climates
    5. Test Conditions Used for Current Metrics in Appendix A
    6. Test Conditions Used for New Metrics in Appendix A1
    7. Provisions Introduced in the AHRI 1340-202X Draft
    a. Cooling Weighting Factors Adjustment
    b. ESP Testing Target Calculation
    c. Test Instructions for Splitting ESP Between Return and Supply 
Duct
    d. Default Fan Power and Maximum Pressure Drop for Coil-Only 
Systems
    e. Component Power Measurement
    f. Non-Standard Low-Static Indoor Fan Motors
    g. IVHE Equations
    8. Heating Test Provisions Not Included in the AHRI 1340-202X 
Draft
    a. General
    b. Definitions of Heating Operating Levels
    c. Boost2 Heating Operating Level and COP25
    d. Extrapolation of Boost Heating Operating Level to 21 [deg]F
    e. Operating Levels Used for Optional COP217 
Representations
    9. Test Procedure Revisions Recommended for a Future Rulemaking
    F. Configuration of Unit Under Test
    1. Summary
    2. Background

[[Page 43987]]

    3. Proposed Approach for Exclusion of Certain Components
    a. Components Addressed Through Test Provisions of 10 CFR Part 
431, Subpart F, Appendices A and A1
    b. Components Addressed Through Representation Provisions of 10 
CFR 429.43
    c. Enforcement Provisions of 10 CFR 429.134
    d. Testing Specially Built Units That Are Not Distributed in 
Commerce
    4. Updates in AHRI 1340-2023
    5. Comments Received and Adopted Provisions
    a. Overall Approach
    b. Coated Coils
    G. Represented Values
    1. Cooling Capacity
    a. Representations of Cooling Capacity
    b. Verification of Cooling Capacity
    2. AEDM Tolerance for IVEC and IVHE
    3. Minimum Part-Load Airflow
    H. Enforcement Procedure for Verifying Cut-In and Cut-Out 
Temperatures
    I. Organization of the Regulatory Text for CUACs and CUHPs
    J. Effective and Compliance Dates
    K. Test Procedure Costs and Impact
    1. Appendix A
    2. Appendix A1
IV. Procedural Issues and Regulatory Review
    A. Review Under Executive Orders 12866, 13563, and 14094
    B. Review Under the Regulatory Flexibility Act
    1. Estimate of Small Entities Regulated
    2. Description and Estimate of Compliance Requirements
    a. Cost and Compliance Associated With Appendix A
    b. Cost and Compliance Associated With Appendix A1
    3. Significant Alternatives to the Rule
    4. Certification Statement
    C. Review Under the Paperwork Reduction Act of 1995
    D. Review Under the National Environmental Policy Act of 1969
    E. Review Under Executive Order 13132
    F. Review Under Executive Order 12988
    G. Review Under the Unfunded Mandates Reform Act of 1995
    H. Review Under the Treasury and General Government 
Appropriations Act, 1999
    I. Review Under Executive Order 12630
    J. Review Under Treasury and General Government Appropriations 
Act, 2001
    K. Review Under Executive Order 13211
    L. Review Under Section 32 of the Federal Energy Administration 
Act of 1974
    M. Congressional Notification
    N. Description of Materials Incorporated by Reference
V. Approval of the Office of the Secretary

I. Synopsis of the Final Rule

    In this final rule, DOE updates its test procedures for CUACs and 
CUHPs by: (1) updating the reference in the Federal test procedure to 
the most recent version of the industry test procedure, AHRI 340/360-
2022, for measuring integrated energy efficiency ratio (``IEER''), 
energy efficiency ratio (``EER''), and coefficient of performance 
(``COP''), consistent with the latest version of ASHRAE Standard 90.1; 
and (2) establishing a new test procedure that references a new 
industry test procedure, AHRI 1340-2023, which is consistent with 
recommendations from the ACUAC and ACUHP Working Group TP Term Sheet, 
including ones for the adoption of new efficiency metrics (i.e., 
integrated ventilation, economizer, and cooling (``IVEC'') and 
integrated ventilation and heating efficiency (``IVHE'')) and new 
testing requirements.
    To implement the changes, DOE is: (1) amending appendix A to 
incorporate by reference AHRI 340/360-2022 for CUACs and CUHPs, while 
maintaining the current efficiency metrics (i.e., EER, IEER, and COP); 
and (2) adding a new appendix A1 to subpart F of 10 CFR part 431. At 10 
CFR 431.96, ``Uniform test method for the measurement of energy 
efficiency of commercial air conditioners and heat pumps,'' DOE is 
listing appendix A1 as the applicable test method for CUACs and CUHPs 
for any subsequent energy conservation standards denominated in terms 
of IVEC and IVHE. Appendix A1 utilizes AHRI 1340-2023, including the 
new IVEC and IVHE efficiency metrics recommended by the ACUAC and ACUHP 
Working Group TP Term Sheet. Use of appendix A1 will not be required 
until such time as compliance is required with any amended energy 
conservation standard based on the new metrics, should DOE adopt such 
standards. After the date on which compliance with appendix A1 is 
required, appendix A will no longer be used as part of the Federal test 
procedure. DOE is also amending certain provisions within DOE's 
regulations for representation and enforcement consistent with the test 
procedure amendments.
    Table I-1 summarizes the adopted amendments to the DOE test 
procedure for CUACs and CUHPs, the test procedure provision prior to 
the amendment, and the reason for each adopted change.

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[GRAPHIC] [TIFF OMITTED] TR20MY24.126

    DOE has determined that the amendments to appendix A will not alter 
the measured efficiency of CUACs and CUHPs or require retesting or 
recertification solely as a result of DOE's adoption of the amendments 
to the test procedure. Additionally, DOE has determined that the 
amendments to appendix A will not increase the cost of testing. 
Representations of energy use or energy efficiency will be required to 
be based on testing in accordance with the amended test procedure in 
appendix A beginning 360 days after the date of publication of this 
test procedure final rule in the Federal Register.
    DOE has determined that the new test procedure at appendix A1 will 
alter the measured efficiency of CUACs and CUHPs and, as a result, 
manufacturers would need to retest, or rerun the alternative efficiency 
determination method where allowed, prior to making any representations 
under the test procedure in appendix A1. Cost estimates for retesting 
are discussed in section III.K of this document. As discussed, use of 
appendix A1 will not be required until the compliance date of any 
amended energy conservation standard denominated in terms of the new 
metrics in appendix A1, should DOE adopt such standards.
    The amendments to representation requirements in 10 CFR 429.43 will 
not be required until either 360 days after publication in the Federal 
Register of this test procedure final rule or beginning on the 
compliance date of amended standards for CUACs and CUHPs based on IVEC 
and IVHE (as applicable), depending on the specific provisions.
    The effective date for the amended test procedures adopted in this 
final rule is 75 days after publication of this document in the Federal 
Register.

II. Authority and Background

    Small, large, and very large commercial package air conditioning 
and heating equipment are included in the list of ``covered equipment'' 
for which DOE is authorized to establish and amend energy conservation 
standards and test procedures. (42 U.S.C. 6311(1)(B)-(D)) Commercial 
package air conditioning and heating equipment includes as equipment 
categories air-cooled commercial unitary air conditioners with a rated 
cooling capacity greater than or equal to 65,000 Btu/h (``ACUACs'') and 
air-cooled commercial unitary heat pumps with a rated cooling capacity 
greater than or equal to 65,000 Btu/h (``ACUHPs''), evaporatively-
cooled commercial unitary air conditioners (``ECUACs''), and water-
cooled commercial unitary air conditioners (``WCUACs''), which are the 
subject of this final rule.\1\ (ECUACs, WCUACs, ACUACs, and ACUHPs, 
which includes double-duct equipment, are collectively referred to as 
``CUACs and CUHPs'' in this document.) DOE's test procedures for CUACs 
and CUHPs are currently prescribed at title 10 of the Code of Federal 
Regulations (``CFR''), part 431, subpart F, Sec.  431.96, table 1. The 
following sections discuss DOE's

[[Page 43989]]

authority to establish and amend test procedures for CUACs and CUHPs 
and relevant background information regarding DOE's amendments to the 
test procedures for this equipment.
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    \1\ While ACUACs with a rated cooling capacity less than 65,000 
Btu/h are included in the broader category of CUACs, they are not 
addressed in this final rule. The test procedure for ACUACs with 
rated cooling capacity less than 65,000 Btu/h have been addressed in 
a separate rulemaking: see Docket No. EERE-2017-BT-TP-0031. All 
references within this final rule to ACUACs and ACUHPs exclude 
equipment with rated cooling capacity less than 65,000 Btu/h.
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A. Authority

    The Energy Policy and Conservation Act, Public Law 94-163 (42 
U.S.C. 6291-6317, as codified), as amended (``EPCA''),\2\ authorizes 
DOE to regulate the energy efficiency of a number of consumer products 
and certain industrial equipment. Title III, Part C \3\ of EPCA, added 
by Public Law 95-619, Title IV, section 441(a), established the Energy 
Conservation Program for Certain Industrial Equipment, which sets forth 
a variety of provisions designed to improve energy efficiency. This 
covered equipment includes small, large, and very large commercial 
package air conditioning and heating equipment. (42 U.S.C. 6311(1)(B)-
(D)) Commercial package air conditioning and heating equipment includes 
CUACs and CUHPs, the subject of this document.
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    \2\ All references to EPCA in this document refer to the statute 
as amended through the Energy Act of 2020, Public Law 116-260 (Dec. 
27, 2020), which reflect the last statutory amendments that impact 
Parts A and A-1 of EPCA.
    \3\ For editorial reasons, upon codification in the U.S. Code, 
Part C was redesignated Part A-1.
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    The energy conservation program under EPCA consists essentially of 
four parts: (1) testing; (2) labeling; (3) Federal energy conservation 
standards, and (4) certification and enforcement procedures. Relevant 
provisions of EPCA include definitions (42 U.S.C. 6311), energy 
conservation standards (42 U.S.C. 6313), test procedures (42 U.S.C. 
6314), labeling provisions (42 U.S.C. 6315), and the authority to 
require information and reports from manufacturers (42 U.S.C. 6316; 42 
U.S.C. 6296).
    The Federal testing requirements consist of test procedures that 
manufacturers of covered equipment must use as the basis for: (1) 
certifying to DOE that their equipment complies with the applicable 
energy conservation standards adopted pursuant to EPCA (42 U.S.C. 
6316(b); 42 U.S.C. 6296), and (2) making other representations about 
the efficiency of that equipment (42 U.S.C. 6314(d)). Similarly, DOE 
uses these test procedures to determine whether the equipment complies 
with relevant standards promulgated under EPCA.
    Federal energy efficiency requirements for covered equipment 
established under EPCA generally supersede State laws and regulations 
concerning energy conservation testing, labeling, and standards. (42 
U.S.C. 6316(a) and (b); 42 U.S.C. 6297) DOE may, however, grant waivers 
of Federal preemption in limited circumstances for particular State 
laws or regulations, in accordance with the procedures and other 
provisions of EPCA. (42 U.S.C. 6316(b)(2)(D))
    Under 42 U.S.C. 6314, EPCA sets forth the criteria and procedures 
DOE must follow when prescribing or amending test procedures for 
covered equipment. Specifically, EPCA requires that any test procedures 
prescribed or amended under this section must be reasonably designed to 
produce test results which reflect energy efficiency, energy use, or 
estimated annual operating cost of a given type of covered equipment 
(or class thereof) during a representative average use cycle (as 
determined by the Secretary) and requires that such test procedures not 
be unduly burdensome to conduct. (42 U.S.C. 6314(a)(2)-(3))
    EPCA generally requires that, at least once every seven years, DOE 
evaluate test procedures for each type of covered equipment, including 
CUACs and CUHPs, to determine whether amended test procedures would 
more accurately or fully comply with the requirements for the test 
procedures to not be unduly burdensome to conduct and be reasonably 
designed to produce test results that reflect energy efficiency, energy 
use, and estimated operating costs during a representative average use 
cycle. (42 U.S.C. 6314(a)(1)-(3)) DOE refers to these provisions as the 
``lookback'' provisions and rulemakings conducted under these 
provisions as ``lookback'' rulemakings.
    Specific to certain commercial equipment, including CUACs and 
CUHPs, EPCA requires that the test procedures be those generally 
accepted industry testing procedures or rating procedures developed or 
recognized by AHRI or ASHRAE, as referenced in ASHRAE Standard 90.1, 
``Energy Standard for Buildings Except Low-Rise Residential Buildings'' 
(``ASHRAE Standard 90.1''). (42 U.S.C. 6314(a)(4)(A)) Further, if such 
an industry test procedure is amended, DOE must update its test 
procedure to be consistent with the amended industry test procedure 
unless DOE determines, by rule published in the Federal Register and 
supported by clear and convincing evidence, that the amended test 
procedure would not meet the requirements in 42 U.S.C. 6314(a)(2) and 
(3) related to representative use and test burden, in which case DOE 
may establish an amended test procedure that does satisfy those 
statutory provisions. (42 U.S.C. 6314(a)(4)(B) and (C)) DOE refers to 
these provisions as the ``ASHRAE trigger'' provisions and rulemakings 
conducted under these provisions as ``ASHRAE trigger'' rulemakings. As 
noted in the recent update to DOE's procedures, interpretations, and 
policies for consideration of new or amended energy conservation 
standards and test procedures, DOE considers an ASHRAE trigger to occur 
only when ASHRAE Standard 90.1 is updated to include an amended 
industry test procedure, and that referenced test procedure includes 
amendments relative to the existing DOE test procedure. 89 FR 24340, 
24351 (April 8, 2024).
    Whether pursuant to the lookback provision or the trigger 
provision, if DOE determines that a test procedure amendment is 
warranted, the Department must publish proposed test procedures in the 
Federal Register, and afford interested persons an opportunity (of not 
less than 45 days duration) to present oral and written data, views, 
and arguments on the proposed test procedures. (42 U.S.C. 6314(b)) If 
DOE determines that test procedure revisions are not appropriate, DOE 
must publish in the Federal Register its determination not to amend the 
test procedures. (42 U.S.C. 6314(a)(1)(A)(ii))
    DOE is publishing this final rule in satisfaction of its 
aforementioned statutory obligations under EPCA. Specifically, in 
accordance with the ASHRAE trigger provisions at 42 U.S.C. 
6314(a)(4)(B), DOE is updating appendix A to reference the most recent 
version of the industry test procedure, AHRI 340/360-2022, which was 
adopted in ASHRAE Standard 90.1-2022, and which includes amendments 
relative to the existing Federal test procedure at appendix A to 
subpart F to 10 CFR part 431.\4\ Pursuant to section 6314(a)(4)(B), DOE 
also evaluated whether AHRI 340/360-2022 could provide representative 
results for the new efficiency metrics recommended by the Working Group 
(i.e., IVEC and IVHE). While AHRI 340/360-2022 provides representative 
results for the current energy efficiency metrics, IEER, EER, and COP, 
it does not include, among other things, operating modes other than 
mechanical-cooling-only operation in the cooling metric, part-load 
heating tests, higher ESP requirements, or crankcase heater operation, 
which are integral to the IVEC and IVHE metrics recommended

[[Page 43990]]

by the Working Group. A more complete discussion of the differences 
between the current efficiency metrics and the IVEC and IVHE efficiency 
metrics can be found in section III.D. Accordingly, as detailed below, 
DOE has determined, supported by clear and convincing evidence, that 
AHRI 340/360-2022 cannot provide representative energy use results for 
the IVEC and IVHE efficiency metrics.
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    \4\ As discussed in section I.B of this document, DOE was also 
triggered by updated industry test procedures in ASHRAE Standard 
90.1-2016 and ASHRAE Standard 90.1-2019, both of which included 
amendments relative to the existing Federal test procedure. However, 
ASHRAE Standard 90.1-2022, and its referenced industry test 
procedure, AHRI 340/360-2022, supersedes these previous versions.
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    As a result, consistent with 42 U.S.C. 6314(a)(4)(C), DOE is 
establishing a new test procedure, appendix A1, to measure energy use 
for the IVEC and IVHE efficiency metrics. DOE has determined that 
appendix A1 is reasonably designed to reflect energy use for the IVEC 
and IVHE efficiency metrics during a representative average use cycle 
without being unduly burdensome to conduct. (See 42 U.S.C. 
6314(a)(4)(C); id. section 6314 (a)(2)) In particular, DOE notes that 
appendix A1 includes: (1) a more mathematically accurate representation 
of cooling efficiency; (2) an integrated heating metric rather than the 
single-point full-load COP metric, which includes performance at 
multiple outdoor air temperatures as well as other operating modes not 
previously accounted for in the COP metric (i.e., part-load heating, 
heating-season ventilation hours, unoccupied no-load hours, and 
supplemental electric resistance heat operation); (3) operating modes 
other than mechanical-cooling-only operation in the cooling metric 
(i.e., integrated mechanical and economizer cooling, economizer-only 
cooling, cooling season ventilation, unoccupied no-load hours); (4) 
higher external static pressure (``ESP'') requirements; (5) crankcase 
heater operation; and (6) oversizing of units in field installations.
    As DOE has determined that the updated version of the industry test 
procedure, AHRI 340/360-2022, adopted in appendix A is more 
representative than the previous version of the test procedure 
referenced in appendix A (because it would more fully comply with the 
requirements that the test procedure be not unduly burdensome to 
conduct and be reasonably designed to produce test results that reflect 
energy efficiency, energy use, and estimated operating costs during a 
representative average use cycle) and because the test procedure 
adopted in appendix A1 is more representative for the new IVEC and IVHE 
metrics, this rulemaking also satisfies DOE's obligations under the 
lookback provisions at 42 U.S.C. 6314(a)(1)(A). For more details on the 
improved representativeness of AHRI 340/360-2022, see section III.E of 
this document.

B. Background

    DOE's existing test procedure for CUACs and CUHPs appears at 10 CFR 
431.96 (Uniform test method for the measurement of energy efficiency of 
commercial air conditioners and heat pumps). The test procedure for 
ACUACs and ACUHPs with a rated cooling capacity of greater than or 
equal to 65,000 Btu/h specified in 10 CFR 431.96 references appendix A 
to subpart F of part 431 (``Uniform Test Method for the Measurement of 
Energy Consumption of Air-Cooled Small (>=65,000 Btu/h), Large, and 
Very Large Commercial Package Air Conditioning and Heating Equipment,'' 
referred to as ``appendix A'' in this document). Appendix A references 
certain sections of ANSI/AHRI Standard 340/360-2007, ``2007 Standard 
for Performance Rating of Commercial and Industrial Unitary Air-
Conditioning and Heat Pump Equipment,'' approved by ANSI on October 27, 
2011 and updated by addendum 1 in December 2010 and addendum 2 in June 
2011 (``ANSI/AHRI 340/360-2007''); ANSI/ASHRAE Standard 37-2009, 
``Methods of Testing for Rating Electrically Driven Unitary Air-
Conditioning and Heat Pump Equipment'' (``ANSI/ASHRAE 37-2009''); and 
specifies other test procedure requirements related to minimum external 
static pressure (``ESP''), optional break-in period, refrigerant 
charging, setting indoor airflow, condenser head pressure controls, 
standard airflow and air quantity, tolerance on capacity at part-load 
test points, and condenser air inlet temperature for part-load tests.
    The DOE test procedure for ECUACs and WCUACs with a rated cooling 
capacity of greater than or equal to 65,000 Btu/h specified in 10 CFR 
431.96 incorporates by reference ANSI/AHRI 340/360-2007, excluding 
section 6.3 of ANSI/AHRI 340/360-2007 and including paragraphs (c) and 
(e) of 10 CFR 431.96.\5\ The DOE test procedure for ECUACs and WCUACs 
with a rated cooling capacity of less than 65,000 Btu/h incorporates by 
reference ANSI/AHRI Standard 210/240-2008, ``2008 Standard for 
Performance Rating of Unitary Air-Conditioning & Air-Source Heat Pump 
Equipment,'' approved by ANSI on October 27, 2011 and updated by 
addendum 1 in June 2011 and addendum 2 in March 2012 (``ANSI/AHRI 210/
240-2008''), excluding section 6.5 of ANSI/AHRI 210/240-2008 and 
including paragraphs (c) and (e) of 10 CFR 431.96.
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    \5\ Paragraphs (c) and (e) of 10 CFR 431.96 address optional 
break-in provisions and additional provisions regarding set-up, 
respectively.
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    On October 26, 2016, ASHRAE published ASHRAE Standard 90.1-2016, 
which included updates to the test procedure references for CUACs and 
CUHPs (excluding CUACs and CUHPs with a rated cooling capacity less 
than 65,000 Btu/h) to reference AHRI Standard 340/360-2015, ``2015 
Standard for Performance Rating of Commercial and Industrial Unitary 
Air-Conditioning and Heat Pump Equipment'' (``AHRI 340/360-2015'').\6\ 
This action by ASHRAE triggered DOE's obligations under 42 U.S.C. 
6314(a)(4)(B), as outlined previously because AHRI 340/360-2015 
included substantive changes compared to the current DOE test procedure 
at appendix A to subpart F of 10 CFR part 431. On July 25, 2017, DOE 
published a request for information (``RFI'') (``July 2017 TP RFI'') in 
the Federal Register to collect information and data to consider 
amendments to DOE's test procedures for certain categories of 
commercial package air conditioning and heating equipment including 
CUACs and CUHPs. 82 FR 34427.
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    \6\ The previous version of ASHRAE Standard 90.1 (i.e., ASHRAE 
Standard 90.1-2013) references ANSI/AHRI 340/360-2007.
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    At the time DOE published the July 2017 TP RFI, the applicable 
version of ASHRAE Standard 90.1 was the 2016 edition, which referenced 
AHRI Standard 340/360-2015, ``2015 Standard for Performance Rating of 
Commercial and Industrial Unitary Air-Conditioning and Heat Pump 
Equipment'' as the test procedure for CUACs and CUHPs. However, on 
October 24, 2019, ASHRAE published ASHRAE Standard 90.1-2019, which 
updated the relevant AHRI Standard 340/360 reference to the 2019 
edition, ``2019 Standard for Performance Rating of Commercial and 
Industrial Unitary Air-Conditioning and Heat Pump Equipment'' (``AHRI 
340/360-2019''). This action by ASHRAE again triggered DOE's 
obligations under 42 U.S.C. 6314(a)(4)(B), as outlined previously, 
because AHRI 340/360-2019 included substantive changes compared to the 
current DOE test procedure at appendix A to subpart F of 10 CFR part 
431. In January 2022, AHRI published additional updates to its test 
procedure standard for CUACs and CUHPs, with the publication of AHRI 
Standard 340/360-2022, ``2022 Standard for Performance Rating of 
Commercial and Industrial Unitary Air-conditioning and Heat Pump 
Equipment'' (``AHRI 340/360-2022''), which DOE references in

[[Page 43991]]

the amended test procedure in appendix A to subpart F of 10 CFR part 
431, as established in this final rule.
    For ECUACs and WCUACs with a rated cooling capacity less than 
65,000 Btu/h, ASHRAE Standard 90.1-2016 references ANSI/AHRI 210/240-
2008, which is referenced by the current Federal test procedure at 10 
CFR 431.96 for this equipment. After the publication of the July 2017 
RFI, AHRI published AHRI Standard 210/240-2017, ``2017 Standard for 
Performance Rating of Unitary Air-conditioning & Air-source Heat Pump 
Equipment'' (``AHRI 210/240-2017''). ASHRAE Standard 90.1-2019 updated 
its reference to AHRI 210/240-2017 as the test procedure for ECUACs and 
WCUACs with rated cooling capacities less than 65,000 Btu/h. This 
action by ASHRAE triggered DOE's obligations under 42 U.S.C. 
6314(a)(4)(B), as outlined previously, because AHRI 210/240-2017 
included substantive changes compared to the current DOE test procedure 
for ECUACs and WCUACs with a rated cooling capacity less than 65,000 
Btu/h at 10 CFR 431.96. However, after the publication of AHRI 210/240-
2017, AHRI released two updates to that industry standard: (1) AHRI 
Standard 210/240-2017 with Addendum 1, ``2017 Standard for Performance 
Rating of Unitary Air-conditioning & Air-source Heat Pump Equipment'' 
(``AHRI 210/240-2017 with Addendum 1''), which was published in April 
2019; and (2) AHRI Standard 210/240-2023, ``2023 Standard for 
Performance Rating of Unitary Air-conditioning & Air-source Heat Pump 
Equipment'' (``AHRI 210/240-2023''), which was published in May 
2020.\7\
---------------------------------------------------------------------------

    \7\ AHRI 210/240-2023 notes at the beginning of the standard 
that while it was first published in May 2020, it establishes a 
method to rate residential central air conditioners and heat pumps 
consistent with the Federal test procedure for residential central 
air conditioners and heat pumps codified in 10 CFR part 430, subpart 
B, appendix M1 (``appendix M1''). Appendix M1 was required to be 
used coincident with the January 1, 2023 compliance date of Federal 
energy conservation standards denominated in terms of seasonal 
energy efficiency ratio 2 (``SEER2''), energy efficiency ratio 2 
(``EER2''), and heating seasonal performance factor 2 (``HSPF2''). 
Therefore, despite being published in May 2020, this version was 
named AHRI 210/240-2023.
---------------------------------------------------------------------------

    On May 12, 2020, DOE published an RFI in the Federal Register 
regarding energy conservation standards for ACUACs, ACUHPs, and 
commercial warm air furnaces (``May 2020 ECS RFI''). 85 FR 27941. In 
response to the May 2020 ECS RFI, DOE received comments from various 
stakeholders, including ones related to the test procedure for ACUACs 
and ACUHPs.
    On May 25, 2022, DOE published an RFI in the Federal Register 
regarding test procedures and energy conservations standards for CUACs 
and CUHPs (``May 2022 TP/ECS RFI''). 87 FR 31743.
    On July 29, 2022, DOE published in the Federal Register a notice of 
intent to establish a working group for commercial unitary air 
conditioners and heat pumps (``Working Group'') to negotiate proposed 
test procedures and amended energy conservation standards for this 
equipment (``July 2022 Notice of Intent''). 87 FR 45703. The Working 
Group was established under the Appliance Standards and Rulemaking 
Federal Advisory Committee (``ASRAC'') in accordance with the Federal 
Advisory Committee Act (FACA) (5 U.S.C. App 2) and the Negotiated 
Rulemaking Act (``NRA'') (5 U.S.C. 561-570, Pub. L. 104-320). The 
purpose of the Working Group was to discuss, and if possible, reach 
consensus on recommended amendments to the test procedures and energy 
conservation standards for ACUACs and ACUHPs. The Working Group 
consisted of 14 voting members, including DOE. (See appendix A, Working 
Group Members, to Document No. 65 in Docket No. EERE-2022-BT-STD-0015) 
On December 15, 2022, the Working Group signed a term sheet of 
recommendations regarding ACUAC and ACUHP test procedures to be 
submitted to ASRAC, the contents of which are referenced throughout 
this final rule (referred to hereafter as the ``ACUAC and ACUHP Working 
Group TP Term Sheet''). (See Id.) The ACUAC and ACUHP Working Group TP 
Term Sheet was approved by ASRAC on March 2, 2023. These 
recommendations are discussed further in section III.D of this final 
rule.
    In January 2023, ASHRAE published ASHRAE Standard 90.1-2022, which 
included updates to the test procedure references for CUACs and CUHPs 
with cooling capacities greater than or equal to 65,000 Btu/h, 
specifically referencing AHRI 340/360-2022. For ECUACs and WCUACs with 
capacities less than 65,000 Btu/h, ASHRAE Standard 90.1-2022 references 
AHRI 210/240-2023. Notably, ECUACs and WCUACs with a rated cooling 
capacity less than 65,000 Btu/h were removed from the scope of AHRI 
210/240-2023 and are instead included in the scope of AHRI 340/360-
2022.\8\ DOE discusses this change in scope to the industry test 
procedure and comments received related to ECUACs and WCUACs with a 
cooling capacity less than 65,000 Btu/h in section III.E.3 of this 
final rule. These actions by ASHRAE again triggered DOE's obligations 
under 42 U.S.C. 6314(a)(4)(B) for ACUACs and ACUHPs, as outlined 
previously, because AHRI 340/360-2022 again included substantive 
changes compared to the current DOE test procedure at appendix A to 
subpart F of 10 CFR 431. While DOE was triggered previously with the 
publication of ASHRAE 90.1-2016 and ASHRAE 90.1-2019, the latest 
version, ASHRAE 90.1-2022, and its referenced industry test procedure, 
AHRI 340/360-2022, supersedes these previous versions. Therefore, in 
this final rule DOE evaluated the amendments under ASHRAE 90.1-2022 
(i.e., AHRI 340/360-2022) relative to the current Federal test 
procedures for the CUACs and CUHPs.
---------------------------------------------------------------------------

    \8\ ECUACs and WCUACs with a rated cooling capacity greater than 
or equal to 65,000 Btu/h are included in the scope of ANSI/AHRI 340/
360-2007 and continue to be included in scope of the latest version 
of AHRI 340/360 (i.e., AHRI 340/360-2022).
---------------------------------------------------------------------------

    DOE published a notice of proposed rulemaking (``NOPR'') in the 
Federal Register on August 17, 2023, presenting DOE's proposals to 
amend the CUAC and CUHP test procedure (``August 2023 TP NOPR''). 88 FR 
56392. The August 2023 TP NOPR also summarized and responded to 
comments pertaining to test procedures for CUACs and CUHPs received in 
response to the July 2017 TP RFI, the May 2020 ECS RFI, and the May 
2022 TP/ECS RFI. Id. DOE held a public webinar related to the August 
2023 TP NOPR on September 7, 2023 (hereafter, the ``NOPR public 
webinar'').
    DOE received comments in response to the August 2023 TP NOPR from 
the interested parties listed in Table II-1, along with each 
commenter's abbreviated name used throughout this final rule. 
Discussion of relevant comments and DOE's responses are provided in 
appropriate sections of this document.

[[Page 43992]]

[GRAPHIC] [TIFF OMITTED] TR20MY24.127

    A parenthetical reference at the end of a comment quotation or 
paraphrase provides the location of the item in the public record.\9\ 
To the extent that interested parties have provided written comments 
that are substantively consistent with any oral comments provided 
during the September 7, 2023 NOPR public webinar, DOE cites the written 
comments throughout this final rule. DOE did not identify any oral 
comments provided during the NOPR public webinar that are not 
substantively addressed by written comments.
---------------------------------------------------------------------------

    \9\ The parenthetical reference provides a reference for 
information located in the docket of DOE's rulemaking to develop 
test procedures for CUACs and CUHPs. (Docket No. EERE-2023-BT-TP-
0014, which is maintained at www.regulations.gov) The references are 
arranged as follows: (commenter name, comment docket ID number, page 
of that document).
---------------------------------------------------------------------------

    In response to the August 2023 TP NOPR, DOE received multiple 
comments regarding energy conservation standards for CUACs and CUHPs, 
particularly regarding standards for ECUACs, WCUACs, and double-duct 
systems. Comments regarding energy conservation standards are outside 
the scope of consideration for this test procedure rulemaking and are 
not addressed in this final rule. Topics related to energy conservation 
standards for CUACs and CUHPs would be addressed in separate rulemaking 
processes.
    Following the publication of the August 2023 TP NOPR, AHRI 
published AHRI Standard 1340-2023, ``2023 Standard for Performance 
Rating of Commercial and Industrial Unitary Air-conditioning and Heat 
Pump Equipment'' (``AHRI 1340-2023''). This is an update to AHRI 
Standard 340/360 that incorporates the recommendations in the ACUAC and 
ACUHP Working Group TP Term Sheet. This updated industry standard has 
not yet been adopted in ASHRAE Standard 90.1, and as such does not 
constitute an ASHRAE trigger, as outlined previously.

III. Discussion

    In the following sections, DOE outlines certain amendments to its 
test procedures for CUACs and CUHPs. For each amendment, DOE provides 
relevant background information, explains why the amendment is 
necessary, discusses relevant public comments, and discusses the 
approach DOE has implemented.

A. Scope of Applicability

    This rulemaking applies to ACUACs and ACUHPs with a rated cooling 
capacity greater than or equal to 65,000 Btu/h, including double-duct 
air conditioners and heat pumps, as well as ECUACs and WCUACs of all 
capacities. Definitions that apply to CUACs and CUHPs are discussed in 
section III.B of this final rule.
    DOE's regulations for CUACs and CUHPs cover both single-package 
units and split systems. See the definition of ``commercial package 
air-conditioning and heating equipment'' at 10 CFR 431.92. A split 
system consists of a condensing unit--which includes a condenser coil, 
condenser fan and motor, and compressor--that is paired with a separate 
component that includes an evaporator coil to form a complete 
refrigeration circuit for space conditioning. One application for

[[Page 43993]]

condensing units is to be paired with an air handler (which includes an 
evaporator coil), such that the combined system (i.e., the condensing 
unit with air handler) meets the definition of a split system CUAC or 
CUHP. It should be pointed out that AHRI has a certification program 
for unitary large equipment that includes certification of CUACs, 
CUHPs, and condensing units. DOE notes that as part of the AHRI 
certification program for unitary large equipment, manufacturers who 
sell air-cooled condensing units with a rated cooling capacity greater 
than or equal to 65,000 Btu/h and less than 135,000 Btu/h must certify 
condensing units as a complete system (i.e., paired with an air 
handler) according to the AHRI 340/360 test procedure.\10\ However, for 
condensing units with a rated cooling capacity greater than or equal to 
135,000 Btu/h and less than 250,000 Btu/h, the AHRI certification 
program allows manufacturers to certify condensing units as a complete 
system according to AHRI 340/360 or optionally certify as a condensing 
unit only according to AHRI Standard 365, ``Standard for Performance 
Rating of Commercial and Industrial Unitary Air-Conditioning Condensing 
Units'' (``AHRI 365'').
---------------------------------------------------------------------------

    \10\ See appendix A of the AHRI Unitary Large Equipment 
Certification Program Operations Manual (January 2024). This can be 
found at www.ahrinet.org/system/files/2023-10/ULE_OM.pdf.
---------------------------------------------------------------------------

    In the August 2023 TP NOPR, DOE emphasized that these AHRI testing 
and certification requirements differ from the Federal test procedure 
at 10 CFR 431.96, which requires testing to ANSI/AHRI 340/360-2007 and 
does not permit certifying to DOE as a condensing unit only according 
to AHRI 365. 88 FR 56392, 56398-56399 (August 17, 2023). Additionally, 
the AHRI certification program does not include unitary split systems 
or condensing units with cooling capacities above 250,000 Btu/h, 
whereas the Federal test procedure and standards (codified at 10 CFR 
431.96 and 431.97, respectively) cover all CUACs and CUHPs with cooling 
capacities up to 760,000 Btu/h. Once again, in the August 2023 TP NOPR, 
DOE emphasized that condensing unit models distributed in commerce with 
air handlers with cooling capacities up to 760,000 Btu/h are covered as 
commercial package air-conditioning and heating equipment (see 
definition at 10 CFR 431.92), and as such, they are subject to the 
Federal regulations specified for CUACs and CUHPs regarding test 
procedures (10 CFR 431.96), energy conservation standards (10 CFR 
431.97), and certification and representation requirements (10 CFR 
429.43). 88 FR 56392, 56398-56399 (August 17, 2023).
    In response to the August 2023 TP NOPR, DOE received several 
comments regarding DOE's clarification of coverage of condensing units. 
Trane commented that single-package and split-system equipment are 
included in the DOE regulation, but stated that the AHRI certification 
program structure specific to split systems exists for several reasons. 
(Trane, No. 14 at p. 2) Trane stated that split systems between 65,000 
Btu/h and 250,000 Btu/h are often matched sets, but split systems 
between 135,000 Btu/h to 250,000 Btu/h may be installed in applications 
where a stand-alone condenser is matched in the field with a non-
matched air-handling unit, which Trane commented warrants a separate 
stand-alone condenser rating. Trane stated that in larger split-system 
applications (with capacities greater than 250,000 Btu/h) condensing 
units are often paired with: (1) semi-custom and custom air-handling 
units that are unique to that installation; (2) more than one air-
handling unit, or (3) air-handling units manufactured by different HVAC 
manufacturers, or the system is built up in the field and all controls 
for the system are installed on site. Trane asserted that even 
considering only the air handlers offered by a single manufacturer, 
there would be thousands of condenser and air handler combinations that 
would require testing, alternative efficiency determination method 
(``AEDM'') development, and certification. Trane also stated that in 
split-system replacements, condensing units are often replaced more 
frequently than the air-handling unit. Id.
    AHRI commented that certifying condensing units as a complete 
system (paired with an air handler) is appropriate for the capacity 
range between 65,000 and 135,000 Btu/h, but that rating models with 
capacities greater than or equal to 135,000 Btu/h as either a complete 
system (using AHRI 340/360) or as a condensing unit only (using AHRI 
365) allows manufacturers to provide condensing units for installation 
in a system that may be connected to a number of different indoor 
equipment types. (AHRI, No. 15 at pp. 4-5) AHRI commented that using 
AHRI 365 to rate models allows manufacturers to meet customer needs 
when indoor equipment and controls with which the condensing unit would 
be paired in the field are not known. AHRI stated that there is no 
procedure in AHRI 340/360 nor AHRI 1340 for rating outdoor units such 
as condensing units without an indoor match. Furthermore, AHRI 
commented that DOE had not investigated the impact of this proposed 
change sufficiently and asserted that there could be serious 
consequences. Id.
    In response to concerns raised by AHRI and Trane, DOE emphasizes 
that the clarification provided in the August 2023 TP NOPR regarding 
the coverage of condensing units paired with air handlers is not a 
change from the existing requirements for rating these models. Neither 
the current DOE test procedure nor the amended test procedures adopted 
in this final rule reference AHRI 365 for testing or rating condensing 
units only. Accordingly, in this final rule, DOE reiterates that 
condensing unit models distributed in commerce with air handlers with 
cooling capacities up to 760,000 Btu/h are covered as commercial 
package air-conditioning and heating equipment (see definition at 10 
CFR 431.92), and as such, they are subject to the Federal regulations 
specified for CUACs and CUHPs regarding test procedures (10 CFR 
431.96), energy conservation standards (10 CFR 431.97), and 
certification and representation requirements (10 CFR 429.43).
    Regarding Trane's assertion as to the extent of testing, AEDM 
development, and certification needed, DOE notes that its regulations 
do not require that ratings for CUACs and CUHPs (including split 
systems that comprise a condensing unit and air handler) be developed 
through testing, and that AEDMs can be used to rate all such systems. 
DOE further notes that to the extent that manufacturers have developed 
simulations of condensing unit model performance in accordance with 
AHRI 365, such simulations could be used as the basis of an AEDM to 
rate condensing units paired with air handlers, provided the AEDM 
satisfies the minimum requirements specified at 10 CFR 429.70(c).

B. Definitions

1. CUAC and CUHP Definition
    As in this final rule, DOE has previously used the colloquial terms 
``commercial unitary air conditioners'' and ``commercial unitary heat 
pump'' (i.e., CUACs and CUHPs), to refer to certain commercial package 
air conditioning and heating equipment, recognizing that CUAC is not a 
statutory term and is not currently used in the CFR. See 79 FR 58948, 
58950 (Sept. 30, 2014); 80 FR 52676, 52676 (Sept. 1, 2015). As codified 
in regulation, the classes for which EPCA prescribed standards have 
been grouped under the headings ``commercial air conditioners

[[Page 43994]]

and heat pumps'' (10 CFR 431.96(b), table 1) and ``air conditioning and 
heating equipment'' (10 CFR 431.97(b), table 1), although these are not 
defined terms. These classes have also been identified by the broader 
equipment type with which they are associated (i.e., small, large, or 
very large commercial package air conditioning and heating equipment). 
Id.
    In the August 2023 TP NOPR, DOE proposed to establish a definition 
for ``commercial unitary air conditioner and commercial unitary heat 
pump'' to assist in distinguishing between the regulated categories of 
commercial package air conditioning and heating equipment. 88 FR 56392, 
56399-56400 (August 17, 2023). The proposed definition was structured 
to indicate categories of commercial package air conditioning and 
heating equipment that are excluded from the definition, rather than 
stipulating features or characteristics of CUACs and CUHPs. The 
proposed definition excluded single package vertical air conditioners 
and heat pumps (``SPVUs''), variable refrigerant flow multi-split air 
conditioners and heat pumps, and water-source heat pumps. Specifically, 
DOE proposed to define ``commercial unitary air conditioner and 
commercial unitary heat pump'' as any small, large, or very large air-
cooled, water-cooled, or evaporatively-cooled commercial package air 
conditioning and heating equipment that consists of one or more 
factory-made assemblies that provide space conditioning; but does not 
include: (1) single package vertical air conditioners and heat pumps; 
(2) variable refrigerant flow multi-split air conditioners and heat 
pumps; (3) water-source heat pumps; (4) equipment marketed only for use 
in computer rooms, data processing rooms, or other information 
technology cooling applications, and (5) equipment only capable of 
providing ventilation and conditioning of 100-percent outdoor air 
marketed only for ventilation and conditioning of 100-percent outdoor 
air. Id. at 88 FR 56399. DOE also requested comment on the proposed 
definition for ``commercial unitary air conditioners and heat pumps.'' 
Id. at 88 FR 56400.
    DOE received feedback from several commenters regarding the 
proposed definition for CUACs and CUHPs. AHRI, Rheem, and Trane 
commented that they did not agree that the proposed definition for 
CUACs and CUHPs is necessary or addresses any existing problems. (AHRI, 
No. 15 at p. 3; Rheem, No. 12 at pp. 1-2; Trane, No. 14 at p. 3) AHRI 
asserted that manufacturers, regulators, and design engineers 
understand the phrase ``unitary central air conditioners and central 
air-conditioning heat pumps for commercial application'' within the 
existing definition for ``commercial package air-conditioning and 
heating equipment'' as referring to CUACs and CUHPs. (AHRI, No. 15 at 
p. 3) AHRI also stated that the proposed definition for CUACs and CUHPs 
creates a circular reference to the existing definition of ``Commercial 
package air-conditioning and heating equipment.'' (Id.) AHRI further 
asserted that the proposed definition for CUACs and CUHPs should not be 
implemented, as the term is not referenced (or proposed) in 42 U.S.C. 
6311. (Id at p. 4) AHRI did not support any changes that would separate 
small, large, or very large commercial package air conditioning and 
heating equipment from their designation as ``ASHRAE equipment'' per 42 
U.S.C. 6313. (Id.)
    Carrier, NEEA, and NYSERDA supported the proposed definition of 
``commercial unitary air conditioner and commercial unitary heat 
pump.'' (Carrier, No. 8 at pp. 1-2; NEEA, No. 16 at pp. 3-4; NYSERDA, 
No. 13 at p. 3) Carrier recommended DOE also adopt the definitions for 
``Commercial and Industrial Unitary Air-Conditioning Equipment'' and 
``Commercial and Industrial Unitary Heat Pump'' in sections 3.4 and 3.5 
of AHRI 340/360-2022 and sections 3.5 and 3.6 of AHRI 1340-202X Draft 
to provide additional clarity. (Carrier, No. 8 at pp. 1-2) NYSERDA 
recommended including ``packaged or split'' in the definition for 
additional clarity. (NYSERDA, No. 13 at p. 3)
    NEEA also commented that the definition proposed for CUACs and 
CUHPs includes excluded products, which appeared contradictory to DOE's 
statement that models can meet the definition for multiple equipment 
categories. (NEEA, No. 16 at pp. 3-4) NEEA requested clarification 
regarding DOE's intent with the proposed definition. (Id.) AHRI also 
requested clarification as to why DOE used distinct descriptions for 
the fourth and fifth exclusions in the proposed CUAC and CUHP 
definition rather than using the already defined terms in 10 CFR 
431.92, ``Computer room air conditioners,'' and ``Unitary dedicated 
outdoor air systems'' respectively. (AHRI, No. 15 at pp. 3-4)
    After consideration of the comments received and upon further 
review, DOE is declining to finalize the proposed definition for CUACs 
and CUHPs in this final rule. DOE may consider adopting a definition 
for CUACs and CUHPs in a future rulemaking action.
2. Basic Model Definition
    The current definition for ``basic model'' in DOE's regulations 
includes a provision applicable for ``small, large, and very large air-
cooled or water-cooled commercial package air conditioning and heating 
equipment (excluding air-cooled, three-phase, small commercial package 
air conditioning and heating equipment with a cooling capacity of less 
than 65,000 Btu/h).'' 10 CFR 431.92. Additionally, the term in the 
current ``basic model'' definition includes ACUACs, ACUHPs, and WCUACs, 
but does not explicitly include ECUACs. However, the definition of 
``commercial package air-conditioning and heating equipment'' at 10 CFR 
431.92 makes clear that that term includes evaporatively-cooled 
equipment. Consequently, ECUACs are part of the relevant basic model 
definition, so the omission of the term ``evaporatively-cooled'' from 
the heading should not impact the proper functioning and use of the 
test procedure.
    In the August 2023 TP NOPR, DOE proposed to update the definition 
of ``basic model'' so that this provision instead applies to the 
proposed defined term ``commercial unitary air conditioner and 
commercial unitary heat pump,'' which would also inherently include 
evaporatively-cooled equipment. 88 FR 56392, 56400 (August 17, 2023). 
DOE also proposed editorial changes more generally to the definition of 
``basic model'' specified in 10 CFR 431.92 to address that the current 
wording could be misinterpreted to read as a definition of each 
equipment category, rather than as the definition of what constitutes a 
basic model for each equipment category. Id.
    DOE did not receive any comments in response to its proposal to 
update the definition for ``basic model.'' As discussed in section 
III.B.1, DOE is not finalizing the proposed defined term ``commercial 
unitary air conditioner and commercial unitary heat pump.'' As such, 
DOE is applying the definition of ``basic model'' to the existing 
defined term ``commercial package air-conditioning and heating 
equipment'' at 10 CFR 431.92. Therefore, other than this terminology 
change, DOE is amending the definition for ``basic model'' as proposed, 
for the reasons discussed in the preceding paragraphs and in the August 
2023 TP NOPR.
3. Double-Duct Definition
    DOE established a definition for ``double-duct air conditioner or 
heat pump'' at 10 CFR 431.92 (referred to as ``double-duct air 
conditioners and heat

[[Page 43995]]

pumps'' or ``double-duct systems'') in an energy conservation standards 
direct final rule published in the Federal Register on January 15, 2016 
(``January 2016 Direct Final Rule''). 81 FR 2420, 2529. This definition 
was included in a term sheet by the ASRAC working group for commercial 
package air conditioners (``Commercial Package Air Conditioners Working 
Group'') as part of the rulemaking that culminated with the January 
2016 Direct Final Rule. (See Document No. 93 in Docket No. EERE-2013-
BT-STD-0007, pp. 4-5) DOE defines ``double-duct systems'' as air-cooled 
commercial package air conditioning and heating equipment that: (1) is 
either a horizontal single package or split-system unit or a vertical 
unit that consists of two components that may be shipped or installed 
either connected or split; (2) is intended for indoor installation with 
ducting of outdoor air from the building exterior to and from the unit, 
as evidenced by the unit and/or all of its components being non-
weatherized, including the absence of any marking (or listing) 
indicating compliance with UL 1995,\11\ ``Heating and Cooling 
Equipment,'' or any other equivalent requirements for outdoor use; (3) 
if it is a horizontal unit, a complete unit has a maximum height of 35 
inches; if it is a vertical unit, a complete unit has a maximum depth 
of 35 inches; and (4) has a rated cooling capacity greater than or 
equal to 65,000 Btu/h and up to 300,000 Btu/h. 10 CFR 431.92.
---------------------------------------------------------------------------

    \11\ Underwriters Laboratory (UL) 1995, UL Standard for Safety 
for Heating and Cooling Equipment (UL 1995).
---------------------------------------------------------------------------

    In the August 2023 TP NOPR, DOE proposed to amend the ``double-duct 
air conditioner or heat pump'' definition consistent with the 
definition in both AHRI 340/360-2022 and the AHRI 1340-202X Draft. 88 
FR 56392, 56400-56401 (August 17, 2023). AHRI 340/360-2022 and the AHRI 
1340-202X Draft specify the following definition for ``double-duct 
systems'': an air conditioner or heat pump that complies with all of 
the following: (1) is either a horizontal single package or split-
system unit; or a vertical unit that consists of two components that 
can be shipped or installed either connected or split; or a vertical 
single packaged unit that is not intended for exterior mounting on, 
adjacent interior to, or through an outside wall; (2) is intended for 
indoor installation with ducting of outdoor air from the building 
exterior to and from the unit, where the unit and/or all of its 
components are non-weatherized; (3) if it is a horizontal unit, the 
complete unit shall have a maximum height of 35 in. or the unit shall 
have components that do not exceed a maximum height of 35 in. If it is 
a vertical unit, the complete (split, connected, or assembled) unit 
shall have components that do not exceed maximum depth of 35 in.; (4) 
has a rated cooling capacity greater than and equal to 65,000 Btu/h and 
less than or equal to 300,000 Btu/h.
    In comparison to DOE's definition, DOE noted the following 
regarding the definition for double-duct system in AHRI 340/360-2022 
and the AHRI 1340-202X Draft: (1) vertical single packaged units not 
intended for exterior mounting on, adjacent interior to, or through an 
outside wall can be classified as double-duct systems; (2) the maximum 
dimensions apply to each component of a split system; and (3) the AHRI 
340/360-2022 and AHRI 1340-202X Draft definition does not include 
compliance with UL 1995 as a criterion for determining whether a model 
is non-weatherized. In the August 2023 TP NOPR, DOE tentatively 
concluded that the definition for ``double-duct system'' in section 3.7 
of AHRI 340/360-2022 and section 3.12 of the AHRI 1340-202X Draft more 
appropriately classifies double-duct systems and differentiates this 
equipment from other categories of commercial package air conditioning 
and heating equipment. 88 FR 56392, 56400-56401 (August 17, 2023).
    DOE did not receive comment regarding the proposed revisions to the 
definition for ``double-duct air conditioner or heat pump.'' DOE has 
determined that the substance of the definitions for ``double-duct 
system'' in AHRI 340/360-2022 and AHRI 1340-2023 better implement the 
intent of DOE and the Commercial Package Air Conditioners Working Group 
to create a separate equipment class of ACUACs and ACUHPs that are 
designed for indoor installation and that require ducting of outdoor 
air from the building exterior. 81 FR 2420, 2446 (Jan. 15, 2016). Thus, 
DOE is revising the definition of ``double-duct air conditioner or heat 
pump'' in 10 CFR 431.92 as proposed in the August 2023 TP NOPR, which 
is consistent with the definition in section 3.2.7 of AHRI 1340-2023.
4. Metric Definitions
    As mentioned in sections III.D.1 and III.D.2, and discussed in 
further detail in section III.E of this final rule, DOE is adopting new 
cooling and heating metrics in appendix A1 (i.e., IVEC and IVHE). 
Additionally, DOE is adopting three metrics for optional 
representations in appendix A1, as discussed further in section III.E.6 
of this final rule: energy efficiency ratio 2 (``EER2''), coefficient 
of performance 2 (``COP2''), and IVHE for colder climates 
(``IVHEC''). In the August 2023 TP NOPR, DOE proposed to add 
new definitions at 10 CFR 431.92 for the terms ``IVEC,'' ``IVHE,'' 
``EER2,'' and ``COP2'' that describe what each metric represents, the 
test procedure used to determine each metric, and specific designations 
applicable to each metric (e.g., IVHEC). 88 FR 56392, 56401 
(August 17, 2023). DOE did not receive comment on the proposed 
definitions for ``IVEC,'' ``IVHE,'' ``EER2,'' and ``COP2.'' Therefore, 
DOE is adopting the definitions as proposed in the August 2023 TP NOPR.

C. Updates to Industry Standards

    The following sections discuss the changes included in the most 
recent updates to AHRI 340/360 and ASHRAE 37, which are incorporated by 
reference in the current DOE test procedure for ACUACs and ACUHPs with 
a rated cooling capacity greater than or equal to 65,000 Btu/h at 10 
CFR 431.96 and 10 CFR part 431, subpart F, appendix A. AHRI 340/360 is 
also incorporated by reference in the current DOE test procedure for 
ECUACs and WCUACs with a rated cooling capacity greater than or equal 
to 65,000 Btu/h at 10 CFR 431.96. The following sections also discuss 
the new industry test standard, AHRI 1340-2023, which DOE is 
incorporating by reference for use in the new DOE test procedure for 
CUACs and CUHPs at 10 CFR part 431, subpart F, appendix A1.
1. AHRI 340/360
    As noted previously, DOE's current test procedures for ACUACs, 
ACUHPs, and ECUACs and WCUACs with a rated cooling capacity greater 
than or equal to 65,000 Btu/h incorporates by reference ANSI/AHRI 340/
360-2007. DOE's current test procedure for ECUACs and WCUACs with a 
rated cooling capacity less than 65,000 Btu/h incorporates by reference 
ANSI/AHRI 210/240-2008.
    The most recent version of ASHRAE Standard 90.1 (i.e., ASHRAE 
Standard 90.1-2022) references AHRI 340/360-2022 as the test procedure 
for ACUACs, ACUHPs, and ECUACs and WCUACs with a rated cooling capacity 
greater than or equal to 65,000 Btu/h. ASHRAE Standard 90.1-2022 
included updates to the test procedure references for ECUACs and WCUACs 
with capacities less than 65,000 Btu/h to reference AHRI 210/240-2023. 
However, ECUACs and WCUACs with capacities less than 65,000 Btu/h are 
outside of the scope of AHRI 210/240-2023 and are instead included in 
AHRI 340/360-2022. Given

[[Page 43996]]

these changes to the relevant industry test standards, DOE believes 
that such reference was an oversight.
    The following list includes substantive additions in AHRI 340/360-
2022 as compared to the current Federal test procedures that apply to 
CUACs and CUHPs, which reference ANSI/AHRI 340/360-2007 and ANSI/AHRI 
210/240-2008:
    1. A method for testing double-duct systems at non-zero outdoor air 
ESP (see section 6.1.3.7 and appendix I of AHRI 340/360-2022);
    2. A method for comparing relative efficiency of indoor integrated 
fan and motor combinations (``IFMs'') that allows CUACs and CUHPs with 
non-standard (i.e., higher ESP) IFMs to be rated in the same basic 
model as otherwise identical models with standard IFMs (see section 
D4.2 of appendix D of AHRI 340/360-2022);
    3. Requirements for indoor and outdoor air condition measurement 
(see appendix C of AHRI 340/360-2022);
    4. Detailed provisions for setting indoor airflow and ESP (see 
sections 6.1.3.3-6.1.3.5 of AHRI 340/360-2022) and refrigerant charging 
instructions to be used in cases in which manufacturer's instructions 
conflict or are incomplete (see section 5.8 of AHRI 340/360-2022); and
    5. ECUACs and WCUACs with cooling capacities less than 65,000 Btu/h 
are included within the scope of the standard.
    As discussed, DOE is amending its test procedure for CUACs and 
CUHPs by incorporating by reference AHRI 340/360-2022 in appendix A. 
Section III.E discusses the specific sections of AHRI 340/360-2022 that 
DOE references in the amendments to appendix A adopted in this final 
rule. As discussed, DOE is adopting these amendments in accordance with 
the requirement that the test procedures for commercial package air 
conditioning and heating equipment be those generally accepted industry 
testing procedures or rating procedures developed or recognized by AHRI 
or ASHRAE, as referenced in ASHRAE Standard 90.1. (42 U.S.C. 
6314(a)(4)(A)) As DOE has noted, ASHRAE Standard 90.1 references an 
incorrect industry standard for ECUACs and WCUACs with capacities less 
than 65,000 Btu/h, AHRI 210/240-2023, so DOE is amending appendix A to 
reference the applicable industry standard, AHRI 340/360-2022.
2. AHRI 1340
    The recommendations of the ACUAC and ACUHP Working Group TP Term 
Sheet have been incorporated into an updated version of AHRI 340/360, 
denoted as AHRI 1340-2023, which supersedes AHRI 340/360-2022, but has 
not yet been adopted in ASHRAE Standard 90.1. In the August 2023 TP 
NOPR, DOE proposed to adopt the AHRI 1340-202X Draft, a draft version 
of AHRI 1340 available at the time. DOE noted its intent to update its 
incorporation by reference to the final published version of the AHRI 
1340-202X Draft, unless there were substantive changes between the 
draft and published versions. 88 FR 56392, 56402 (August 17, 2023). 
Differences between the ACUAC/ACUHP Working Group TP Term Sheet, the 
AHRI 1340-202X Draft, and AHRI 1340-2023 are discussed in the 
paragraphs that follow.
    The AHRI 1340-202X Draft proposed for adoption in the August 2023 
TP NOPR includes recommendations from the ACUAC and ACUHP Working Group 
TP Term Sheet described in section III.D of this final rule (including 
the IVEC and IVHE metrics). The AHRI 1340-202X Draft also included the 
following revisions and additions to the IVEC and IVHE metrics not 
included in the ACUAC and ACUHP Working Group TP Term Sheet, which are 
discussed in detail in section III.E of this final rule:
    1. Detailed test instructions for splitting ESP between the return 
and supply ductwork, consistent with ESP requirements recommended in 
the ACUAC and ACUHP Working Group TP Term Sheet;
    2. Corrections to the hour-based IVEC weighting factors included in 
the ACUAC and ACUHP Working Group TP Term Sheet;
    3. Correction of the equation in the ACUAC and ACUHP Working Group 
TP Term Sheet for calculating adjusted ESP for any cooling or heating 
tests conducted with an airflow rate that differs from the full-load 
cooling airflow;
    4. Addition of separate hour-based weighting factors and bin 
temperatures to calculate a separate version of IVHE that is 
representative of colder climates, designated IVHEC;
    5. Changes to the default fan power and maximum pressure drop used 
for testing coil-only systems;
    6. Additional instruction for component power measurement during 
testing;
    7. Corrections to equations used for calculating IVHE;
    8. Provisions for testing with non-standard low-static indoor fan 
motors; and
    9. Revision to the power adder for WCUACs that reflects power that 
would be consumed by field-installed heat rejection components.
    Since publication of the August 2023 TP NOPR, the AHRI 1340-202X 
Draft was finalized and published as AHRI 1340-2023 in December 2023. 
DOE has reviewed AHRI 1340-2023 and has identified that AHRI 1340-2023 
includes the previously discussed revisions and additions to the IVEC 
and IVHE metrics in the AHRI 1340-202X Draft that were not included in 
the ACUAC and ACUHP Working Group TP Term Sheet. AHRI 1340-2023 also 
includes several revisions and updates to the test procedures specified 
in the AHRI 1340-202X Draft. DOE reviewed these revisions and updates, 
which include the following items, and discusses them in detail in 
sections III.E.3, III.E.7, III.E.8, III.F, and III.H of this document. 
Those sections also include discussion of the justification for 
adopting the content of these changes (which are largely consistent 
with corresponding proposals in the August 2023 TP NOPR) in this final 
rule.
    1. A method for calculating capacity and fan power adjustments for 
coil-only systems operating at part-load airflow, consistent with DOE's 
proposal in the August 2023 TP NOPR;
    2. Addition of a method to verify cut-in and cut-out temperatures, 
consistent with DOE's proposal in the August 2023 TP NOPR but with 
additional specificity;
    3. Addition of an optional boost 2 test for optional 
representations of 5 [deg]F capacity and performance for systems with 
more than two operating levels;
    4. Allowance for the test conducted at 5 [deg]F and 17 [deg]F at 
the boost heating operating level to be used for IVHE bins ranging from 
5 [deg]F to 21 [deg]F;
    5. Revisions to appendix D of AHRI 1340 to align with the specific 
components approach proposed by DOE in the August 2023 TP NOPR, and 
inclusion of provision for how to test models with drain pan heaters 
present; and
    6. Revisions to the test temperatures for ECUACs and WCUACs and 
corresponding revision to the tower fan and pump power values for 
WCUACs.
    Consistent with the proposals in the August 2023 TP NOPR, in this 
final rule DOE is incorporating by reference AHRI 1340-2023 in the new 
test procedure at appendix A1 as DOE has determined, supported by clear 
and convincing evidence, that AHRI 340/360-2022 cannot provide 
representative energy use results for the IVEC and IVHE efficiency 
metrics. Further, DOE has determined that AHRI 1340-2023 would not be 
unduly burdensome to conduct and reflects energy efficiency during a 
representative average use cycle for the

[[Page 43997]]

IVEC and IVHE efficiency metrics. Specific aspects of AHRI 1340-2023 
are discussed in more detail in section III.E. Section III.E of this 
document also discusses comments received on DOE's proposal to adopt 
the AHRI 1340-202X Draft, as well as the specific sections of AHRI 
1340-2023 that DOE references in appendix A1.
3. ASHRAE 37
    ANSI/ASHRAE 37-2009, which provides a method of test for many 
categories of air conditioning and heating equipment, is referenced for 
testing CUACs and CUHPs by AHRI 340/360-2022 and AHRI 1340-2023. More 
specifically, sections 5 and 6 and appendices C, D, and E of AHRI 340/
360-2022 and sections 5 and 6 and appendices C, D, and E of AHRI 1340-
2023 reference methods of test in ANSI/ASHRAE 37-2009. DOE currently 
incorporates by reference ANSI/ASHRAE 37-2009 in 10 CFR 431.95, and the 
current incorporation by reference applies to the current Federal test 
procedure for ACUACs and ACUHPs specified at appendix A. The current 
Federal test procedures at 10 CFR 431.96 for ECUACs and WCUACs do not 
explicitly reference ANSI/ASHRAE 37-2009. In the August 2023 TP NOPR, 
DOE proposed to maintain the incorporation by reference of ANSI/ASHRAE 
37-2009 to the proposed appendix A, which would also apply ANSI/ASHRAE 
37-2009 to testing ECUACs and WCUACs, and to incorporate by reference 
ANSI/ASHRAE 37-2009 for use with appendix A1. 88 FR 56392, 56402 
(August 17, 2023). DOE did not receive any comments regarding its 
proposal to incorporate by reference ANSI/ASHRAE 37-2009 to both 
appendices A and A1. Therefore, as proposed, DOE is maintaining its 
incorporation by reference of ANSI/ASHRAE 37-2009 in appendix A and 
incorporating by reference ANSI/ASHRAE 37-2009 in appendix A1. Section 
III.E of this document discusses the specific sections of ANSI/ASHRAE 
37-2009 that DOE references in appendices A and A1.

D. Term Sheet Recommendations and Metrics

    As previously mentioned, DOE published in the Federal Register the 
July 2022 Notice of Intent. 87 FR 45703 (July 29, 2022). DOE then 
established the Working Group in accordance with FACA and NRA. The 
Working Group consisted of 14 members and met six times, while the 
Working Group's subcommittee met an additional seven times. The Working 
Group meetings were held between September 20, 2022, and December 15, 
2022, after which the Working Group successfully reached consensus on 
an amended test procedure. The Working Group signed a term sheet of 
recommendations on December 15, 2022. (See EERE-2022-BT-STD-0015-0065) 
The Working Group addressed the following aspects of the test procedure 
for ACUACs and ACUHPs:
    1. Mathematical representation of cooling efficiency: The current 
cooling metric specified by AHRI 340/360-2022 (i.e., IEER) represents a 
weighted average of the measured energy efficiency ratios (EER) 
measured at four distinct test conditions, whereas the IVEC metric is 
calculated as the total annual cooling capacity divided by the total 
annual energy use, as discussed further in section III.D.1 of this 
document. The Working Group agreed that this calculation approach 
provides a more mathematically accurate way of representing the cooling 
efficiency of ACUACs and ACUHPs compared to the current approach used 
for IEER. As part of this equation format, the IVEC metric also uses 
hour-based weighting factors to represent the time spent per year in 
each operating mode.
    2. Integrated heating metric: The current heating metric for ACUHPs 
(i.e., COP) represents the ratio of heating capacity to the power 
input, calculated at a single test condition of 47 [deg]F. COP does not 
account for the performance at part-load or over the range of 
temperatures seen during an average heating season, and it does not 
include energy use in heating season ventilation mode. IVHE accounts 
for both full-load and part-load operation at a range of typical 
ambient temperatures seen during the heating season, and it includes 
energy use in heating season ventilation mode. Analogous to IVEC, the 
IVHE metric is calculated as the total annual heating load divided by 
the total annual energy use, as discussed further in section III.D.2 of 
this document, and the metric also uses hour-based weighting factors to 
represent the time spent per year in each operating mode.
    3. Operating modes other than mechanical cooling: The IEER metric 
currently does not include the energy use of operating modes other than 
mechanical cooling, such as economizer-only cooling and cooling season 
ventilation. The newly established IVEC metric includes the energy use 
of these other modes.
    4. ESP: The IVEC and IVHE metrics require increased ESPs--in 
comparison to the ESPs required for determining IEER and COP--to more 
accurately represent ESPs and corresponding indoor fan power that would 
be experienced in real-world installations.
    5. Crankcase heater operation: The current IEER metric includes 
crankcase heater power consumption only when operating at part-load 
compressor stages (i.e., for part-load cooling operation, crankcase 
heater power is included only for higher-stage compressors that are 
staged off, and it is not included for lower-stage compressors when all 
compressors are cycled off). The COP metric does not include any 
crankcase heater power consumption. In contrast, the IVEC and IVHE 
metrics include all annual crankcase heater operation, including when 
all compressors are cycled off in part-load cooling or heating, 
ventilation mode, unoccupied no-load hours, and in heating season (for 
ACUACs only).
    6. Oversizing: The current IEER and COP metrics do not consider 
that ACUACs and ACUHPs are typically oversized in field installations. 
In contrast, the IVEC and IVHE metrics include an oversizing factor of 
15 percent (i.e., it is assumed that the unit's measured full-load 
cooling capacity is 15 percent higher than the peak building cooling 
load and peak building heating load). Accounting for oversizing is more 
representative of the load fractions seen in field applications and 
better enables the test procedure to differentiate efficiency 
improvements from the use of modulating/staged components.
    Based on discussions related to these six topics, the Working Group 
developed the ACUAC and ACUHP Working Group TP Term Sheet, which 
includes the following recommendations:
    1. A recommendation to adopt the latest version of AHRI 340/360-
2022 with IEER and COP metrics required for compliance beginning 360 
days from the date a test procedure final rule publishes (see 
Recommendation #0);
    2. The IVEC efficiency metric, to be required on the date of 
amended energy conservation standards for ACUACs and ACUHPs (see 
Recommendation #1);
    3. Hour-based weighting factors for the IVEC metric (see 
Recommendation #2);
    4. Details on determination of IVEC, including provisions for 
determining IVEC in appendix B of the ACUAC and ACUHP Working Group TP 
Term Sheet (see Recommendation #3);
    5. Target load fractions and temperature test conditions for IVEC, 
which account for oversizing (see Recommendation #4);
    6. A requirement that representations of full-load EER be made in 
accordance

[[Page 43998]]

with the full-load ``A'' test (see Recommendation #5); \12\
---------------------------------------------------------------------------

    \12\ Similar to the current test procedure for determining IEER, 
the test procedure recommended in the ACUAC and ACUHP Working Group 
TP Term Sheet includes four cooling tests designated with letters 
``A,'' ``B,'' ``C,'' and ``D.'' The ``A'' test is a full-load 
cooling test, while the ``B,'' ``C,'' and ``D'' tests are part-load 
cooling tests.
---------------------------------------------------------------------------

    7. A requirement to provide representations of airflow used for the 
full-load ``A'' test and the part-load ``D'' test (i.e., the airflow 
used in the lowest-stage test for the D point), and a provision for 
determining the minimum airflow that can be used for testing (see 
Recommendation #6);
    8. The IVHE efficiency metric (see Recommendation #7);
    9. Hour-based weighting factors, load bins, and outdoor air 
temperatures for each bin (i.e., temperatures used for the building 
heating load line, not test temperature conditions) for the IVHE metric 
(see Recommendation #8);
    10. The test conditions and list of required and optional tests and 
representations for the IVHE metric (see Recommendation #9);
    11. Provisions for manufacturers to certify cut-in and cut-out 
temperatures for heat pumps to DOE and provisions for a DOE 
verification test of those temperatures (see Recommendation #10);
    12. Commitment of the Working Group to analyze ventilation and fan-
only operation included in the IVEC and IVHE metrics to validate that 
these metrics adequately capture fan energy use during the energy 
conservation standards portion of the negotiated rulemaking. If the 
IVEC and IVHE levels do not adequately drive more efficient air moving 
systems that are technologically feasible and economically justified, 
the Working Group committed to developing a metric addressing furnace 
fan energy use (see Recommendation #11);
    13. ESP requirements for the IVEC and IVHE metrics, requirements 
for splitting the ESP requirements between the return and supply ducts, 
and a requirement that certified airflow for full load and D bin be 
made public in the DOE Compliance Certification Database (see 
Recommendation #12);
    14. Provisions requiring manufacturers to certify crankcase heater 
wattages and tolerances for certification (see Recommendation #13); and
    15. Provisions that the contents of the ACUAC and ACUHP Working 
Group TP Term Sheet be implemented in a test procedure NOPR and final 
rule, with the final rule issuing no later than any energy conservation 
standards direct final rule (see Recommendation #14).
    The following sections provide a summary of the development and 
final recommendations regarding the IVEC and IVHE cooling and heating 
metrics in the ACUAC and ACUHP Working Group TP Term Sheet.
1. IVEC
    For the new cooling metric, the Working Group determined to 
prospectively modify the climate zones and building types accounted for 
in the test procedure as compared to those included in the existing DOE 
test procedure, in order to improve the representativeness of the 
metrics to better reflect the broad range of applications of CUACs and 
CUHPs. To do so, the Working Group utilized hour-based weighting 
factors, which represent the average time spent per year in each 
operating mode and load bin. To develop these weighting factors, 
members of the Working Group used building modeling developed by 
Carrier that was based on 10 ASHRAE Standard 90.1 building prototypes 
across all U.S. climate zones. (See EERE-2022-BT-STD-0015-0019) The 
resulting hour-based weighting factors are provided in Recommendation 
#2 of the ACUAC and ACUHP Working Group TP Term Sheet. (See EERE-2022-
BT-STD-0015-0065)
    The ACUAC and ACUHP Working Group concluded that including 
economizer-only cooling and cooling season ventilation operating modes 
in a seasonal cooling metric would improve the representativeness for 
ACUACs and ACUHPs, and as such, included these modes in the IVEC metric 
outlined in Recommendation #1 and the hour-based weighting factors in 
Recommendation #2 of the ACUAC and ACUHP Working Group TP Term Sheet. 
Appendix B of the ACUAC and ACUHP Working Group TP Term Sheet provides 
the recommended calculation method for the IVEC method and includes 
sections specifying the methods for including ventilation and 
economizer-only cooling operation in the calculation of IVEC. (See 
EERE-2022-BT-STD-0015-0065)
    The Working Group also considered ESP requirements for the IVEC and 
IVHE metrics. Stakeholders indicated the need for higher ESP 
requirements to improve representativeness of field performance. 
Additionally, stakeholders discussed the importance of maintaining 
uniformity in testing of units at higher ESP conditions. (See EERE-
2022-BT-STD-0015-0062 at p. 11) The ESP requirements agreed to by the 
Working Group are provided in Recommendation #12 of the ACUAC and ACUHP 
Working Group TP Term Sheet (see EERE-2022-BT-STD-0015-0065) and 
include the following:
    1. Higher ESP requirements for testing: As discussed previously, 
the minimum ESP conditions recommended by the Working Group are 
provided in Table III-1.
[GRAPHIC] [TIFF OMITTED] TR20MY24.128

    2. Economizer pressure drop: ASHRAE Standard 90.1-2022 requires the 
use of economizers for comfort cooling applications for almost all U.S. 
climate zones. The analysis conducted by Carrier in support of the 
Working Group indicates that over 96 percent of buildings require the 
use of economizers. (see EERE-2022-BT-STD-0015-0019 at p. 14) 
Economizers installed in CUACs and CUHPs add internal static pressure 
that the indoor

[[Page 43999]]

fan has to overcome, even when the economizer dampers are closed. The 
current DOE test procedure does not require the installation of an 
economizer on a tested unit, and DOE is aware that manufacturers 
generally do not test CUACs and CUHPs with economizers installed. The 
ESP requirements specified by the current DOE test procedure are the 
same regardless of whether a unit is tested with or without an 
economizer. As such, testing a unit without an economizer does not 
reflect the total static pressure that would be experienced in the 
field for installations that require the use of an economizer. 
Accordingly, in order to better represent the fan power of ACUACs and 
ACUHPs that are typically installed with economizers, the Working Group 
recommended that for all units tested without an economizer installed, 
0.10 in. H2O shall be added to the full-load ESP values specified in 
Table III-1.\13\
---------------------------------------------------------------------------

    \13\ An economizer is an apparatus that supplies outdoor air to 
reduce or eliminate the need for mechanical cooling during mild or 
cooler weather.
---------------------------------------------------------------------------

    3. Return and supply static split requirements: Test procedures for 
CUACs and CUHPs include ESP requirements that reflect the total ESP 
applied within the return and supply ductwork of the test set-up. The 
current Federal test procedure does not specify requirements for how 
ESP is distributed during testing (i.e., the relative contribution from 
return ductwork versus supply ductwork). Given the recommendation to 
increase the required ESP levels for testing, the Working Group 
concluded that the higher ESP conditions could cause variability in 
test results if the distribution of ESP between return ductwork and 
supply ductwork were not specified in the revised test procedure. 
Therefore, to ensure repeatable and reproducible testing conditions for 
CUAC and CUHP units, the Working Group recommended specifying that ESP 
requirements be split with 25 percent applied in the return ductwork 
and the remaining 75 percent applied in the supply ductwork. The 
Working Group further recommended that the fraction of ESP applied in 
the return ductwork shall have a -5/+0 percent tolerance (i.e., the 
return static must be within 20 to 25 percent of the total ESP) for the 
full-load cooling test. In a case where there is no additional 
restriction on the return duct and more than 25 percent of the ESP is 
already applied in the return ductwork without a restriction, then 
greater than 25 percent ESP in the return ductwork will be allowed. 
Once set for the full-load cooling test, these restriction settings 
shall remain unchanged for the other cooling and heating tests 
conducted.
    To incorporate the various changes involved in testing requirements 
and weighting factors already discussed, the Working Group created the 
IVEC metric provided in Recommendation #1 with further specifications 
in appendix B of the ACUAC and ACUHP Working Group TP Term Sheet. The 
IVEC metric is a summation formula analogous to the seasonal energy 
efficiency ratio 2 (``SEER2'') metric designated for residential 
central air conditioner and central air conditioning heat pumps (``CAC/
HP'') equipment. (See appendix M1 to subpart B of 10 CFR part 430, 
``Uniform Test Method for Measuring the Energy Consumption of Central 
Air Conditioners and Heat Pumps.'') Stated simply, the IVEC metric is 
calculated by dividing the total annual cooling capacity by the total 
annual energy use. Key aspects encompassed in the IVEC metric include 
the following:
    1. Accounting for energy consumed in different modes: The IVEC 
metric includes energy use during mechanical cooling, integrated 
mechanical and economizer cooling, economizer-only cooling, cooling 
season ventilation, unoccupied no-load hours, and heating season 
operation of crankcase heat (for CUACs only). Appendix B of the ACUAC 
and ACUHP Working Group TP Term Sheet specifies instructions for 
determining energy consumption during each mode.
    2. Testing parameters: The ACUAC and ACUHP Working Group TP Term 
Sheet further specifies instructions in appendix B for the mechanical 
cooling tests at each target mechanical load. These methodologies and 
tolerances mirror those specified in AHRI 340/360-2022, including a 3-
percent tolerance on the target mechanical load for part-load tests, 
and in cases when the target mechanical load cannot be met within 
tolerance, instructions for using interpolation and cyclic degradation 
to determine the performance at the target test point.
    3. Target load percentages: Recommendation #4 of the ACUAC and 
ACUHP Working Group TP Term Sheet includes target conditions for 
testing, including load percentages for testing units at part-load 
conditions. For each bin, the specified target load percent (%Loadi) 
reflects the average load as a percentage of the full-load capacity for 
that bin met by using all modes of cooling, and is used for determining 
total annual cooling provided in the numerator of the IVEC equation. 
The target mechanical load percent (%Loadi,mech) is the average load 
for each bin met only through mechanical cooling (i.e., mechanical-only 
cooling and the mechanical portion of integrated mechanical and 
economizer cooling) and is the target load fraction used for the part-
load cooling test for each bin.
    As mentioned, the IVEC metric includes the annual operation of 
crankcase heaters for CUACs and CUHPs. Appendix B of the ACUAC and 
ACUHP Working Group TP Term Sheet further specifies the accounting of 
crankcase heater energy consumption in each operating mode. 
Recommendation #2 of the ACUAC and ACUHP Working Group TP Term Sheet 
specifies hour-based weighting factors to account for crankcase heat 
operation in unoccupied no-load cooling season hours for CUACs and 
CUHPs, as well as heating season hours for CUACs. Appendix B of the 
ACUAC and ACUHP Working Group TP Term Sheet also specifies that for 
part-load cooling tests, crankcase heat is accounted for in power 
measurements of higher-stage compressors that are staged off during 
testing, while crankcase heat operation of lower-stage compressors when 
cycled off as well as crankcase heat operation in other operating modes 
is calculated using the certified crankcase heater power.
    The IVEC metric also accounts for a 15-percent oversizing factor. 
Accordingly, the target load percentages specified in Recommendation #4 
include this 15-percent oversizing factor. Additionally, the A test 
condition is excluded from the IVEC calculation; however, the A test is 
still a required test point for determining full-load capacity.
    IVEC includes outdoor and return air dry-bulb and wet-bulb test 
temperatures that differ from those used in the current test procedure 
for determining IEER, as shown in Table III-2.

[[Page 44000]]

[GRAPHIC] [TIFF OMITTED] TR20MY24.129

    The IVEC metric also limits the minimum airflow that can be used 
for testing. This minimum airflow limit calculation method is based on 
the average ventilation rate determined in building modeling performed 
to develop IVEC and is a function of the full-load cooling capacity. 
Unlike AHRI 340/360-2022 (see section 6.1.3.4.5), the provisions for 
determining IVEC do not specify separate test provisions for setting 
airflow during part-load tests of multi-zone variable air volume 
(``MZVAV'') units. Rather, the part-load airflow used for testing all 
CUACs and CUHPs will be based on the certified part-load cooling 
airflow.
2. IVHE
    The IVHE metric specified in the ACUAC and ACUHP Working Group TP 
Term Sheet differs from the COP heating efficiency metric specified in 
the current DOE test procedure by the inclusion of heating season 
operating modes not currently accounted for, a combined seasonal 
performance metric rather than individual ratings at specific 
temperature conditions, and additional optional test conditions. In 
alignment with the development of the IVEC metric described in section 
III.D.1 of this final rule, the Working Group determined to utilize 
hour-based weighting factors to account for heating loads across more 
building types and climate zones than are included in the current DOE 
test procedure. The building heating load lines and hours developed for 
the IVHE metric rely on a similar ASHRAE Standard 90.1 building and 
climate zone analysis as the one conducted for the IVEC metric 
development. Additionally, in developing the heating load line on which 
the hour-based weighting factors rely, the Working Group utilized the 
previously discussed 15-percent oversizing factor and assumed a heat-
to-cool ratio of 1, as outlined in Recommendation #8 (i.e., assumed the 
peak building cooling load equals the peak building heating load).
    The heating rating requirements recommended in the ACUAC and ACUHP 
Working Group TP Term Sheet include several distinct provisions 
regarding testing requirements from the existing DOE test procedure. In 
the current DOE test procedure, CUHPs are required to be tested only at 
a 47 [deg]F full-load condition to generate a COP rating. 
Recommendation #9 of the ACUAC and ACUHP Working Group TP Term Sheet, 
however, introduces several provisions with significant differences 
from the existing DOE test procedure. First, the recommendation 
includes required testing at 47 [deg]F and 17 [deg]F full-load 
conditions, aligning with those previously specified in AHRI 340/360-
2022. Additionally, the recommendation introduces optional part-load 
test conditions at both 47 [deg]F and 17 [deg]F temperature conditions, 
as well as test conditions for optional testing at a 5 [deg]F full-load 
condition. Finally, the recommendation includes test requirements for 
optional boost tests at the 17 [deg]F and 5 [deg]F test conditions for 
variable-speed units. Additionally, the IVHE metric incorporates two 
operating modes previously excluded from the DOE test procedure: 
heating season ventilation mode and supplemental electric resistance 
heat operation. Lastly, the IVHE test conditions rely on the same ESP 
requirements per capacity bin as those specified for IVEC, as detailed 
in Recommendation #12. The airflow provisions pertaining to IVEC 
mentioned in section III.D.1 of this final rule (i.e., a limit on 
minimum airflow used for testing and no separate test provisions for 
MZVAV units) apply to the test provisions for the IVHE metric as well.
    The results from optional and required testing, as well as the 
newly included operating modes, are included in the calculation of the 
IVHE metric utilizing the weighting factors outlined in Recommendation 
#8 and calculation methods from appendix C of the ACUAC and ACUHP 
Working Group TP Term Sheet. The calculation methods for IVHE that 
implement these changes are further detailed in the paragraphs that 
follow.
    The IVHE metric includes contributions from both mechanical and 
resistance heating to meet building heating load. Similar to the IVEC 
calculation approach, the IVHE metric is calculated by dividing the 
total annual building heating load by the total annual energy use.
    Recommendations #8, #9, and #10, as well as appendices B and C of 
the ACUAC and ACUHP Working Group TP Term Sheet, provide the 
calculation methods for the IVHE metric. The hour-based weighting 
factors and bin temperatures for IVHE are included in Recommendation #8 
of the ACUAC and ACUHP Working Group TP Term Sheet, which specifies 10 
distinct load-based bins alongside weighting factors for heating season 
ventilation and operation of crankcase heat in unoccupied no-load 
heating season hours. The calculation methods outlined for the IVHE 
metric in the ACUAC and ACUHP Working Group TP Term Sheet are specified 
as the following:
    1. Building load calculation: Recommendation #8 includes the 
calculation method for the building load in each load bin based on the 
measured full-load cooling capacity.
    2. Interpolation between temperatures: Appendix C of the ACUAC and 
ACUHP Working Group TP Term Sheet specifies interpolation instructions 
for the various test temperatures specified in Recommendation #8. 
Interpolation instructions are specified for bins with temperatures 
between 17 [deg]F and 47 [deg]F. Appendix C also includes the following 
instructions for bins with temperatures less than 17 [deg]F: (1) 
interpolation instructions to be used if the optional

[[Page 44001]]

5 [deg]F test is conducted, and (2) extrapolation instructions 
utilizing the 47 [deg]F and 17 [deg]F test data to be used if the 5 
[deg]F test is not conducted.
    3. Determination of heating stage, auxiliary heat, and cyclic 
degradation: For load bins in which the calculated building load 
exceeds the highest-stage mechanical heating capacity determined for 
the bin temperature, appendix C of the ACUAC and ACUHP Working Group TP 
Term Sheet includes calculation methods for determining the power 
required by auxiliary resistance heat and is included in the overall 
IVHE calculation. For load bins in which the calculated building load 
is lower than the lowest-stage mechanical heating capacity determined 
for the bin temperature, appendix C of the ACUAC and ACUHP Working 
Group TP Term Sheet includes calculation methodology for calculating 
power and incorporating cyclic degradation with a cyclic degradation 
factor of 0.25. This cyclic degradation methodology is consistent with 
the methodology specified in appendix M1 to subpart B of 10 CFR part 
430 for residential central heat pumps. For load bins in which the 
calculated building load is in between the lowest-stage and highest-
stage mechanical heating capacities determined for the bin temperature, 
appendix C of the ACUAC and ACUHP Working Group TP Term Sheet includes 
calculations for determining power based on interpolation between 
performance of mechanical heating stages.
    4. Defrost degradation: The capacity calculations for all load bins 
with temperatures less than 40 [deg]F include a defrost degradation 
coefficient, with calculations specified in appendix C of the ACUAC and 
ACUHP Working Group TP Term Sheet.
    5. Cut-out factor: Recommendation #10 of the ACUAC and ACUHP 
Working Group TP Term Sheet specifies that manufacturers will certify 
cut-in and cut-out temperatures, or the lack thereof, to DOE to ensure 
resistance-only operation is included at temperatures below which 
mechanical heating would not operate. This restriction is implemented 
in calculations through a cut-out factor included in appendix C. DOE is 
not amending the certification or reporting requirements for ACUHPs in 
this final rule to require reporting cut-in and cut-out temperatures. 
Instead, DOE may consider proposals to amend the certification and 
reporting requirements for this equipment under a separate rulemaking 
regarding appliance and equipment certification.
    6. Crankcase heater power contribution: In alignment with the 
inclusion of crankcase heater power contribution in IVEC, appendix C of 
the ACUAC and ACUHP Working Group TP Term Sheet specifies a method for 
incorporating crankcase heat power for all heating season operating 
modes for ACUHPs. Specifically, for part-load heating tests, crankcase 
heat is accounted for in power measurements of higher-stage compressors 
that are staged off during testing, while crankcase heat operation of 
lower-stage compressors when cycled off, as well as crankcase heat 
operation in other operating modes, is calculated using the certified 
crankcase heater power.

E. DOE Adopted Test Procedures and Comments Received

    In the August 2023 TP NOPR, DOE proposed to maintain the current 
efficiency metrics of IEER, EER, and COP in appendix A, and reference 
AHRI 340/360-2022 in appendix A for measuring the existing metrics. 88 
FR 56392, 56403-56404 (August 17, 2023). Additionally, DOE proposed to 
establish a new test procedure at appendix A1 that adopts the substance 
of the AHRI 1340-202X Draft, including the new IVEC and IVHE metrics, 
through incorporation by reference of a finalized version of that 
industry test standard. Id. The following sections discuss DOE's 
proposals, comments received, and DOE's adopted provisions regarding 
(1) AHRI 1340-2023 and the IVEC and IVHE metrics; (2) double-duct 
systems; (3) ECUACs and WCUACs; (4) the IVHE metric for colder 
climates; (5) the test conditions used in appendix A; (6) the test 
conditions used in appendix A1; (7) provisions introduced in the AHRI 
1340-202X Draft that are not included in the ACUAC and ACUHP Working 
Group TP Term Sheet; and (8) heating test provisions introduced in AHRI 
1340-2023.
1. Overall
    As discussed, DOE proposed to establish a new test procedure at 
appendix A1 that would adopt the AHRI 1340-202X Draft, including the 
newly proposed IVEC and IVHE metrics. DOE noted its intent to ideally 
incorporate by reference a finalized version of that industry test 
standard. DOE further stated that if a finalized version of the AHRI 
1340-202X Draft is not published before the test procedure final rule, 
or if there are substantive changes between the draft and published 
versions of the standard that are not supported by stakeholder comments 
in response to this NOPR, DOE may adopt the substance of the AHRI 1340-
202X Draft or provide additional opportunity for comment on the final 
version of that industry consensus standard. Id. As noted in the August 
2023 TP NOPR, certain provisions in the current appendix A and table 1 
to 10 CFR 431.96(b) (e.g., regarding minimum ESP, optional break-in) 
would be redundant with the reference to AHRI 340/360-2022, and, as 
such, DOE proposed to remove those explicit provisions from table 1 to 
10 CFR 431.96(b) and appendix A, and instead reference them through the 
relevant provisions of the updated AHRI 340/360. Id.
    Further, in both appendix A and appendix A1, DOE proposed to 
incorporate by reference ANSI/ASHRAE 37-2009. Id.
    Specifically for appendix A1, DOE proposed to adopt certain 
sections of the AHRI 1340-202X Draft to determine IVEC and IVHE, which 
are generally consistent with the recommendations from the ACUAC and 
ACUHP Working Group TP Term Sheet. Id. The ACUAC and ACUHP Working 
Group TP Term Sheet applies only to the test procedures for ACUACs and 
ACUHPs, excluding double-duct systems. However, the AHRI 1340-202X 
Draft proposed for adoption in the August 2023 TP NOPR, as well as the 
final version of the standard (i.e., AHRI 1340-2023), include 
additional provisions for determining IVEC and IVHE for double-duct 
systems, ECUACs, and WCUACs, indicating industry consensus that these 
metrics are appropriate for these categories of CUACs and CUHPs. Id. 
DOE requested comment on the proposed adoption of the IVEC and IVHE 
metrics as determined using the AHRI 1340-202X Draft in appendix A1 for 
all CUACs and CUHPs. Id.
    On this topic, AHRI, ASAP & ACEEE, Carrier, the CA IOUs, Lennox, 
NEEA, Rheem, and Trane generally supported the proposal to adopt the 
IVEC and IVHE metrics as determined in the AHRI 1340-202X Draft, 
consistent with the ACUAC and ACUHP Working Group TP Term Sheet. (AHRI, 
No. 15 at pp. 1, 5; ASAP & ACEEE, No. 11 at p. 1; Carrier, No. 8 at p. 
2; CA IOUs, No. 10 at pp. 1-2; Lennox, No. 9 at p. 2; NEEA, No. 16 at 
pp. 1-2; Rheem, No. 12 at p. 2, Trane, No. 14 at p. 1) NEEA 
specifically supported the ESP requirements proposed by DOE consistent 
with the recommendations of the ACUAC and ACUHP Working Group TP Term 
Sheet. (NEEA, No. 16 at p. 2) The CA IOUs stated that the new test 
procedure improves representativeness. (CA IOUs, No. 10 at p. 1) AHRI 
and ASAP & ACEEE acknowledged the efforts made by the AHRI Commercial 
Unitary Standards Technical Committee

[[Page 44002]]

(``STC'') and supported the corrections and additions to the ACUAC and 
ACUHP Working Group TP Term Sheet included in the AHRI 1340-202X Draft. 
(AHRI, No. 15 at pp. 1-2; ASAP & ACEEE, No. 11 at p. 1)
    As proposed, DOE is adopting the most recent version of AHRI 
Standard 340/360 (i.e., AHRI 340/360-2022) in appendix A for testing 
CUACs and CUHPs (including ACUACs, ACUHPs, ECUACs, WCUACs, and double-
duct systems) to measure the current metrics--EER, IEER, and COP. 
Specifically, DOE is adopting the following sections of AHRI 340/360-
2022: sections 3 (with certain exclusions \14\), 4, 5, and 6, and 
appendices A, C, D (excluding sections D1 through D3), and E. As 
proposed, DOE is also removing certain provisions from table 1 to 10 
CFR 431.96(b) and the current appendix A that are redundant with the 
reference to AHRI 340/360-2022 adopted in appendix A in this final 
rule. As discussed, DOE is adopting these amendments in accordance with 
the requirement that the test procedures for commercial package air 
conditioning and heating equipment be those generally accepted industry 
testing procedures or rating procedures developed or recognized by AHRI 
or ASHRAE, as referenced in ASHRAE Standard 90.1. (42 U.S.C. 
6314(a)(4)(A))
---------------------------------------------------------------------------

    \14\ DOE is not referencing the following provisions in section 
3 of AHRI 340/360-2022 because the terms are either defined at 10 
CFR 431.92 or are not needed for the DOE test procedure: 3.2 (Basic 
Model), 3.4 (Commercial and Industrial Unitary Air-conditioning 
Equipment), 3.5 (Commercial and Industrial Unitary Heat Pump), 3.7 
(Double-duct System), 3.8 (Energy Efficiency Ratio), 3.12 (Heating 
Coefficient of Performance), 3.14 (Integrated Energy Efficiency 
Ratio), 3.23 (Published Rating), 3.26 (Single Package Air-
Conditioners), 3.27 (Single Package Heat Pumps), 3.29 (Split System 
Air-conditioners), 3.30 (Split System Heat Pump), and 3.36 (Year 
Round Single Package Air-conditioners).
---------------------------------------------------------------------------

    As discussed in section III.C.2 of this document, AHRI 1340-2023 
includes certain updates that are not included in the ACUAC and ACUHP 
Working Group TP Term Sheet. Most of these updates were included in the 
AHRI 1340-202X Draft, and they are discussed in detail in section 
III.E.7 of this final rule. There are also several updates included 
AHRI 1340-2023 that were not included in the AHRI 1340-202X Draft, 
notably regarding ECUACs and WCUACs (discussed in further detail in 
section III.E.3 of this document) and boost heating tests (described in 
further detail in section III.E.8 of this document). Based on comments 
received and DOE's review of AHRI 1340-2023, DOE has determined that 
the updates to the test procedure in AHRI 1340-2023 are appropriate, 
consistent with the intent of the ACUAC and ACUHP Working Group TP Term 
Sheet and the intent of the provisions proposed in the August 2023 TP 
NOPR, and improve the representativeness of the test procedure.
    DOE has determined that the recommendations specified in the ACUAC 
and ACUHP Working Group TP Term Sheet are consistent with the EPCA 
requirement that test procedures for covered equipment, including CUACs 
and CUHPs, be reasonably designed to produce test results that reflect 
energy efficiency, energy use, and estimated operating costs of a type 
of industrial equipment (or class thereof) during a representative 
average use cycle (as determined by the Secretary), and shall not be 
unduly burdensome to conduct (42 U.S.C. 6314(a)(2)). As a result, DOE 
is adopting a new test procedure in appendix A1 in accordance with the 
Term Sheet. Therefore, DOE is amending the test procedure for CUACs and 
CUHPs to adopt in the new appendix A1 the test provisions in AHRI 1340-
2023 and ASHRAE 37-2009. DOE is adopting the following sections of AHRI 
1340-2023 in appendix A1: sections 3 (with certain exclusions),\15\ 4, 
5 (excluding section 5.2), and 6.1 through 6.3, and appendices A, C, D 
(excluding sections D.1 and D.2), and E. Use of appendix A1 will not be 
required until the compliance date of amended energy conservation 
standards denominated in terms of the new metrics in appendix A1, 
should such standards be adopted.
---------------------------------------------------------------------------

    \15\ DOE is not referencing the following provisions in section 
3 of AHRI 1340-2023 because the terms are either defined at 10 CFR 
431.92 or are not needed for the DOE test procedure: 3.2.2 
(Barometric Relief Dampers), 3.2.3 (Basic Model), 3.2.5 (Commercial 
and Industrial Unitary Air-conditioning Equipment), 3.2.5.1 
(Commercial and Industrial Unitary Air-Conditioning System), 3.2.5.2 
(Commercial and Industrial Unitary Heat Pump), 3.2.7 (Double-duct 
System), 3.2.9 (Desiccant Dehumidification Component), 3.2.10 (Drain 
Pan Heater), 3.2.11.1 (Air Economizer), 3.2.12 (Energy Efficiency 
Ratio 2), 3.2.13 (Evaporative Cooling), 3.2.13.1 (Direct Evaporative 
Cooling System), 3.2.13.2 (Indirect Evaporative Cooling System), 
3.2.14 (Fresh Air Damper), 3.2.15 (Fire, Smoke, or Isolation 
Damper), 3.2.17 (Hail Guard), 3.2.19 (Heating Coefficient of 
Performance 2), 3.2.20 (High-Effectiveness Indoor Air Filtration), 
3.2.22 (Indoor Single Package Air-conditioners), 3.2.23 (Integrated 
Ventilation, Economizing, and Cooling Efficiency (IVEC)), 3.2.34 
(Integrated Ventilation and Heating Efficiency (IVHE)), 3.2.29 (Non-
standard Ducted Condenser Fan), 3.2.31.2 (Boost2 Heating Operational 
Level (B2)), 3.2.34 (Power Correction Capacitor), 3.2.35 (Powered 
Exhaust Air Fan), 3.2.36 (Powered Return Air Fan), 3.2.37 (Process 
Heat Recovery, Reclaim, or Thermal Storage Coil), 3.2.38 (Published 
Rating), 3.2.41 (Refrigerant Reheat Coil), 3.2.42 (Single Package 
Air-Conditioners), 3.2.43 (Single Package Heat Pumps), 3.2.45 (Sound 
Trap), 3.2.46 (Split System), 3.2.51 (Steam or Hydronic Heat Coils), 
3.2.53 (UV Lights), 3.2.55 (Ventilation Energy Recovery System 
(VERS)), 3.2.56 (Year Round Single Package Air-conditioners), and 
3.2.57 (Year Round Single Package Heat Pump).
---------------------------------------------------------------------------

    As proposed, for appendices A and A1, DOE is incorporating by 
reference ANSI/ASHRAE 37-2009. Appendices A and A1 reference all 
sections of the industry test standard except sections 1 (Purpose), 2 
(Scope), and 4 (Classifications).
2. Double-Duct Systems
    As discussed in section III.B.3 of this final rule, double-duct 
systems are equipment classes of ACUACs and ACUHPs, either single 
package or split, designed for indoor installation in constrained 
spaces, such that outdoor air must be ducted to and from the outdoor 
coil.
    Pursuant to the current DOE test procedure (which references ANSI/
AHRI 340/360-2007), double-duct systems are tested and rated under the 
same test conditions at zero outdoor air ESP as conventional ACUACs and 
ACUHPs (i.e., that are not double-duct systems). AHRI 340/360-2022 
includes two different set of test provisions that can be used for 
testing double-duct systems. Section 6.1.3.7 of AHRI 340/360-2022 
includes provisions for measuring performance at zero outdoor air ESP 
to determine the EER, IEER, and/or COP metrics, consistent with the 
current DOE test procedure. AHRI 340/360-2022 added an additional test 
method in appendix I for double-duct systems that specifies an outdoor 
air ESP requirement of 0.50 in. H2O for double-duct systems. 
When testing with 0.50 in. H2O outdoor air ESP, ratings are 
designated with the subscript ``DD'' (e.g., EERDD, 
COPDD, and IEERDD) to distinguish them from the 
ratings determined by testing at zero outdoor air ESP. ASHRAE Standard 
90.1-2022 does not include any separate provisions for double-duct 
systems or the EERDD, COPDD, and/or 
IEERDD metrics; therefore, testing per Appendix I to AHRI 
340/360-2022 is not required per ASHRAE Standard 90.1-2022. As a 
result, DOE's statutory obligation to consider the test procedures for 
CUACs and CUHPs referenced in ASHRAE Standard 90.1 (per 42 U.S.C. 
6314(a)(4)(A)) does not include Appendix I to AHRI 340/360-2022.
    The ACUAC and ACUHP Working Group TP Term Sheet did not include 
provisions for double-duct systems. However, the AHRI 1340-202X Draft 
included provisions for determining the new IVEC and IVHE metrics for 
double-duct systems. Specifically, similar to appendix I of AHRI 340/
360-2022, the AHRI 1340-202X Draft applied a 0.50 in. H2O 
outdoor air ESP requirement for determining IVEC and IVHE for double-

[[Page 44003]]

duct systems. Other than this outdoor air ESP requirement, the AHRI 
1340-202X Draft specified no differences in determining IVEC and IVHE 
for double-duct systems as compared to conventional ACUACs and ACUHPs. 
In the August 2023 TP NOPR, DOE proposed to: (1) maintain the existing 
metrics for double-duct systems and reference AHRI 340/360-2022 for 
double-duct systems in appendix A, and (2) adopt the IVEC and IVHE 
metrics for double-duct systems in appendix A1 as specified in the AHRI 
1340-202X Draft. 88 FR 56392, 56421-56422 (August 17, 2023).
    In response, Carrier supported the adoption of the IVEC and IVHE 
metric, as specified in AHRI 1340-202X, in appendix A1, as well as the 
proposal to maintain the test procedure from AHRI 340/360-2022 in 
appendix A without the provisions of appendix I of that test procedure. 
(Carrier, No. 8 at p. 3) AHRI similarly supported the adoption of IVEC 
and IVHE for double-duct systems in appendix A1. (AHRI, No. 15 at p. 2)
    DOE notes that AHRI 1340-2023 maintains the same ESP conditions and 
method for determining IVEC and IVHE for double-duct systems as the 
method specified in the AHRI 1340-202X Draft. Because double-duct 
systems are installed indoors with ducting of outdoor air to and from 
the outdoor coil, DOE has concluded that testing at a non-zero outdoor 
air ESP (as specified in the AHRI 1340-2023) would be more 
representative of field applications than testing at zero outdoor air 
ESP (as specified in the current Federal test procedure). DOE has also 
concluded that the IVEC and IVHE metrics specified in AHRI 1340-2023 
better capture actual energy use in the field than the COP, EER, and 
IEER metrics specified in the current DOE test procedure, for the 
reasons discussed throughout this final rule for ACUACs and ACUHPs more 
generally. Further, DOE has concluded that the application of the IVEC 
and IVHE metrics in AHRI 1340-2023 to double-duct systems reflect 
industry consensus that these metrics are suitable for double-duct 
systems. For these reasons and given the support expressed by 
stakeholders, DOE is adopting the provisions in AHRI 1340-2023 for 
determining IVEC and IVHE for double-duct systems in appendix A1.
    As mentioned previously, the current cooling energy conservation 
standards for double-duct systems are in terms of EER and the current 
heating energy conservation standards are in terms of COP. Testing to 
the IVEC and IVHE metrics will not be required until such time as 
compliance is required with amended energy conservation standards for 
double-duct systems denominated in terms of IVEC and IVHE, should DOE 
adopt such standards. As discussed, DOE is also updating the current 
test procedure for all CUACs and CUHPs, including double-duct systems, 
in appendix A to reference AHRI 340/360-2022, maintaining the current 
EER and COP metrics until the compliance date of any energy 
conservation standards for double-duct systems denominated in terms of 
IVEC and IVHE. As discussed, ASHRAE Standard 90.1-2022 does not include 
any provisions specific to double-duct systems or standards denominated 
in terms of the EERDD, COPDD, and/or 
IEERDD metrics; therefore, testing double-duct systems at 
non-zero outdoor air ESP per Appendix I to AHRI 340/360-2022 which 
generates results in terms of EERDD, COPDD, and/
or IEERDD (as opposed to testing a zero outdoor air ESP per 
section 6.1.3.7 of AHRI 340/360-2022 which generates results in terms 
of EER, COP, and/or IEER) is not required per ASHRAE Standard 90.1-
2022. As a result, DOE's statutory obligation to consider the test 
procedures for CUACs and CUHPs referenced in ASHRAE Standard 90.1 (per 
42 U.S.C. 6314(a)(4)(A)) does not include Appendix I to AHRI 340/360-
2022.
3. ECUACs and WCUACs
a. Overall
    The current DOE test procedure for ECUACs and WCUACs is specified 
at 10 CFR 431.96 and includes the EER metric. The ACUAC and ACUHP 
Working Group TP Term Sheet does not include provisions for ECUACs and 
WCUACs. However, the AHRI 1340-202X Draft includes provisions for 
determining the new IVEC and optional EER2 metric for ECUACs and 
WCUACs. The AHRI 1340-202X Draft and AHRI 1340-2023 provisions for 
determining IVEC and EER2 for ECUACs and WCUACs are largely the same as 
the provisions for ACUACs and ACUHPs; however, there are several 
provisions specific or unique to ECUACs and WCUACs, specifically 
regarding: (1) ESP requirements, (2) test temperatures, and (3) 
accounting for power of WCUAC heat rejection components.
    In the August 2023 TP NOPR, DOE proposed to adopt the IVEC metric 
for ECUACs and WCUACs in appendix A1, as specified in the AHRI 1340-
202X Draft, and sought comment on this proposal, including the test 
temperature requirements. 88 FR 56392, 56419-56420 (August 17, 2023).
    In response to the August 2023 TP NOPR, Carrier supported the 
adoption of the IVEC metric for ECUACs and WCUACs in appendix A1 as 
specified in the proposed AHRI 1340-202X Draft. (Carrier, No. 8 at p. 
2) Carrier also commented that the working version of AHRI 1340 (at the 
time of Carrier's comment) included updated test temperatures for 
determining IVEC and EER2 for ECUACs and WCUACs, and Carrier presented 
these updated test conditions. (Id.) AHRI also expressed support for 
DOE's proposal to adopt the IVEC and IVHE metrics for ECUACs and 
WCUACs. (AHRI, No. 15 at pp. 2, 5)
    Trane supported the product classifications and water temperatures 
for WCUACs in AHRI 1340 but did not support adopting the IVEC metric 
for WCUACs as specified in AHRI 1340. Trane further stated that issues 
specific to WCUACs need to be addressed in order to adopt an IVEC 
metric for WCUACs that is truly representative of field applications. 
Trane asserted that the provisions in AHRI 1340 do not adequately 
consider the difference between indoor and outdoor single package units 
and stated that the vast majority of WCUACs are indoor packaged units. 
Trane further commented that WCUACs installed indoors most often use 
waterside economizers rather than airside economizers and are typically 
installed in the core of a multi-story office building, such that 
outdoor air for economizing or ventilation is not introduced through 
the WCUAC air handling section. Trane also commented that because 
WCUACs typically distribute conditioned air only within a single floor 
of a building, duct runs are typically shorter than for traditional 
rooftop systems, and, therefore, the ESP conditions included in AHRI 
1340 should be different for WCUACs. (Trane, No. 14 at pp. 3-4)
    Regarding Trane's concerns about the IVEC metric for WCUACs, DOE 
acknowledges that WCUACs have a range of applications that may not 
always align with the assumptions included in the analyses to develop 
the IVEC metric. However, DOE notes that this is also true for ACUACs 
and ACUHPs, which serve a wide range of applications and operate in a 
wide variety of different operating conditions. The intent of the IVEC 
metric, as developed by the Working Group, was to representatively 
capture performance of the U.S. national average of CUAC and CUHP 
applications, understanding that this ``average performance'' cannot 
perfectly represent the unique aspects of certain applications. DOE 
notes that the IVEC metric is specified for WCUACs in the recently 
published industry consensus test procedure AHRI 1340-

[[Page 44004]]

2023 consistent with DOE's proposals (with certain updated test 
conditions, as discussed). Therefore, DOE understands AHRI 1340-2023 
and the IVEC metric specified in the test procedure to represent 
general industry consensus on a representative test procedure and 
metric for CUACs and CUHPs, including WCUACs.
    AHRI 1340-2023 includes updates to the provisions for determining 
IVEC for ECUACs and WCUACs--specifically, the test temperature and 
accounting for power of WCUAC heat rejection components. The ESP 
requirements specified for ECUACs and WCUACs are unchanged from the 
AHRI 1340-202X Draft. These provisions are discussed in detail in the 
following subsections. DOE has concluded that the IVEC metric specified 
in AHRI 1340-2023 for ECUACs and WCUACs (including the ESP 
requirements, updated test temperatures, and updated WCUAC heat 
rejection component power allowances) is consistent with the proposed 
adoption of the IVEC metric specified in the AHRI 1340-202X Draft and 
meets the criteria in 42 U.S.C. 6314(a)(2)-(3). Accordingly, DOE is 
adopting the IVEC metric (as well as the optional EER2 metric) and 
associated test provisions specified in AHRI 1340-2023 in appendix A1 
for ECUACs and WCUACs.
    As mentioned previously, the current energy conservation standards 
for ECUACs and WCUACs are in terms of EER. Testing to the IVEC metric 
will not be required until such time as compliance is required with 
amended energy conservation standards for ECUACs and WCUACs denominated 
in terms of IVEC, should DOE adopt such standards. As discussed, DOE is 
also updating the current test procedure for all CUACs and CUHPs, 
including ECUACs and WCUACs, in appendix A to reference AHRI 340/360-
2022, maintaining the current EER metric until the compliance date of 
any energy conservation standards for ECUACs and WCUACs denominated in 
terms of the IVEC metric. As discussed in section III.C.1 of this final 
rule, DOE has concluded that this amendment in Appendix A is consistent 
with the intent of the test procedure references for ECUACs and WCUACs 
in the latest published version of ASHRAE Standard 90.1.
b. ESP Requirements for ECUACs and WCUACs
    The IVEC and EER2 metrics include higher ESP requirements than the 
current DOE test procedures and AHRI 340/360-2022. For ECUACs and 
WCUACs with cooling capacity greater than or equal to 65,000 Btu/h, the 
AHRI 1340-202X Draft specifies the same ESP requirements for 
determining IVEC and EER2 for ECUACs and WCUACs as for ACUACs and 
ACUHPs. For ECUACs and WCUACs with cooling capacity less than 65,000 
Btu/h, there are no air-cooled equipment of comparable cooling capacity 
within the scope of the AHRI 1340-202X Draft. Therefore, the AHRI 1340-
202X Draft includes an ESP requirement of 0.5 in. H2O for 
testing ECUACs and WCUACs with cooling capacity less than 65,000 Btu/h, 
which is consistent with the ESP requirement specified in AHRI 210/240-
2023 for comparable air-cooled equipment (i.e., air-cooled, three-phase 
CUACs and CUHPs with cooling capacity less than 65,000 Btu/h). As 
discussed in the August 2023 TP NOPR, DOE understood that the 
provisions for determining IVEC and EER2 for ECUACs and WCUACs, 
specifically including the higher ESP requirements outlined in the AHRI 
1340-202X Draft, reflect industry consensus that the IVEC metric (and 
optional EER2 metric) provide a more representative measure of energy 
efficiency for ECUACs and WCUACs. 88 FR 56392, 56419-56420 (August 17, 
2023). AHRI 1340-2023 maintains the same ESP requirements as those 
outlined in the AHRI 1340-202X Draft. In this final rule, DOE maintains 
its conclusion that the ESP requirements specified for ECUACs and 
WCUACs in AHRI 1340-2023 are representative of field installations for 
ECUACs and WCUACs. As such, DOE is adopting the ESP requirements for 
testing ECUACs and WCUACs as outlined in AHRI 1340-2023.
c. ECUAC and WCUAC Test Temperatures and WCUAC Heat Rejection 
Components
    ECUACs and WCUACs use different test temperatures than ACUACs and 
ACUHPs, and in the August 2023 TP NOPR, DOE presented test temperature 
requirements for full-load and part-load test points for determining 
IVEC for ECUACs and WCUACs, as specified in the AHRI 1340-202X Draft. 
88 FR 56392, 56419-56420 (August 17, 2023).
    WCUACs are typically installed in the field with separate heat 
rejection components \16\ that reject heat from the water loop to 
outdoor ambient air, but these separate heat rejection components are 
not installed nor is their power measured during testing of WCUACs 
under the current DOE test procedure. These heat rejection components 
typically consist of a circulating water pump (or pumps) and a cooling 
tower. To account for the power that would be consumed by these 
components in field installations, section 6.1.1.7 of AHRI 340/360-2022 
specifies that WCUACs with cooling capacities less than 135,000 Btu/h 
shall add 10.0 W to the total power of the unit for every 1,000 Btu/h 
of cooling capacity.
---------------------------------------------------------------------------

    \16\ Separate heat rejection components (e.g., a cooling tower 
or circulating water pump) are required for WCUACs but not used with 
ACUACs or ECUACs. ACUACs and ECUACs contain all components needed to 
reject heat to the ambient air surrounding the ACUAC or ECUAC. 
WCUACs, however, reject heat to a building's water loop. Separate 
components are needed to circulate the water in the water loop and 
reject heat from the water loop to the ambient air surrounding the 
building.
---------------------------------------------------------------------------

    Section 6.2.4.3 of the AHRI 1340-202X Draft includes similar 
provisions for accounting for the power of heat rejection components 
for WCUACs to those in AHRI 340/360-2022. However, unlike AHRI 340/360-
2022, the heat rejection component power addition was not limited to 
units with cooling capacities less than 135,000 Btu/h in the AHRI 1340-
202X Draft, and instead, it applied to WCUACs of all cooling 
capacities. DOE proposed the adoption of the approach specified in the 
AHRI 1340-202X Draft in the August 2023 TP NOPR. 88 FR 56392, 56420-
56421 (August 17, 2023).
    As noted by Carrier's comment (summarized in section III.E.3.a of 
this document), based on further discussions and analysis in AHRI 
Commercial Unitary STC meetings after the issuance of the AHRI 1340-
202X Draft, the test conditions for ECUACs and WCUACs were updated in 
the published AHRI 1340-2023. Additionally, AHRI 1340-2023 includes 
different values to account for the power of heat rejection components 
of WCUACs as compared to the AHRI 1340-202X Draft. Both of these 
changes were related to a changed assumption in operation of cooling 
towers in water loops serving WCUACs.
    The analysis conducted to develop the heat rejection component 
power adder and the WCUAC entering water temperature (``EWT'') test 
conditions in the AHRI 1340-202X Draft assumed constant cooling tower 
fan speed regardless of load level. In other words, the analysis to 
develop the AHRI 1340-202X Draft method assumed that the cooling tower 
fans do not slow down when there is less heat to reject in the cooling 
tower, and thus: (1) the cooling tower fan power does not reduce at 
lower load levels; and (2) the cooling tower approach \17\ reduces 
significantly

[[Page 44005]]

at lower load levels. Specifically, as the cooling load reduces, the 
same amount of cooling tower airflow is being provided to reject less 
heat in the cooling tower, so the water is cooled in the cooling tower 
to a temperature closer to the outdoor air wet-bulb temperature, and, 
therefore, the water leaving the cooling tower (and entering the WCUAC) 
is at a lower temperature, resulting in a lower WCUAC EWT test 
condition.
---------------------------------------------------------------------------

    \17\ For an evaporative cooling tower, the ``cooling tower 
approach'' is the difference between the cold water temperature 
(i.e., the temperature of the cooled water leaving the cooling 
tower) and the outdoor air wet-bulb temperature.
---------------------------------------------------------------------------

    The analysis conducted to develop the heat rejection component 
power adder and the WCUAC EWT test conditions in AHRI 1340-2023 assumes 
that variable frequency drives (``VFDs'') are used on cooling tower 
fans to reduce cooling tower fan speed (and thus cooling tower fan 
power) for lower cooling loads. The use of VFDs on cooling tower fans 
impacts both the cooling tower fan power and the WCUAC EWT. First, the 
cooling tower fan VFD reduces cooling tower fan power at part load. 
Therefore, instead of a single power adder in W per 1,000 Btu/h of 
cooling capacity applied regardless of the test being conducted (i.e., 
independent of the test bin) as specified in the AHRI 1340-202X Draft, 
AHRI 1340-2023 includes four different condenser tower fan and pump 
power rate adders (in units of W per 1,000 Btu/h of cooling capacity)--
a separate adder for each test bin, with the adders decreasing at lower 
load levels. Second, the reduced cooling tower fan speed at part load 
means that the cooling tower approach does not significantly reduce at 
lower load levels, because cooling tower airflow driving heat transfer 
in the cooling tower reduces along with the amount of heat 
rejected.\18\ Correspondingly, the WCUAC part-load EWT test conditions 
in AHRI 1340-2023 are higher than the EWT test conditions in the AHRI 
1340-202X Draft. The EWT test conditions for WCUACs in AHRI 1340-2023, 
which were developed based on the assumption that VFDs are used on 
cooling tower fans to reduce cooling tower fan speed, are the same as 
those included in Carrier's comment (Carrier, No. 8 at p. 2) in 
response to the August 2023 TP NOPR.
---------------------------------------------------------------------------

    \18\ For the AHRI 1340-2023 EWTs, the assumed cooling tower 
approach is the same for B, C, and D bins -i.e., as shown in Table 
III-3 and Table III-4, the difference between the outdoor air wet-
bulb temperature in Table III-3 and the EWT in Table III-4 is 8 
[deg]F for the B, C, and D bins. Therefore, the EWT test conditions 
in AHRI 1340-2023 decrease for each part-load bin by the same amount 
as the outdoor air wet-bulb temperature test conditions.
---------------------------------------------------------------------------

    Additionally, AHRI 1340-2023 includes slight changes to the outdoor 
air wet-bulb temperature test conditions for ECUACs, based on updated 
analysis of representative temperatures. The outdoor air wet-bulb 
temperature requirements for ECUACs in AHRI 1340-2023 are the same as 
those included in Carrier's comment (Carrier, No. 8 at p. 2) in 
response to the August 2023 TP NOPR.
    Table III-3 and Table III-4 show the test temperatures included in 
the AHRI 1340-202X Draft and the final test temperatures included in 
AHRI 1340-2023 for ECUACs and WCUACs, respectively.
[GRAPHIC] [TIFF OMITTED] TR20MY24.130

[GRAPHIC] [TIFF OMITTED] TR20MY24.131


[[Page 44006]]


    Regarding the minor revisions to the ECUAC outdoor air wet-bulb 
temperatures in AHRI 1340-2023, DOE has concluded that these updated 
temperatures are representative of applications for ECUACs, and that 
adopting these slight updates to the proposed ECUAC test temperatures 
is consistent with the intent of the proposed approach and with 
comments from Carrier that included these updated temperatures. 
Therefore, in this final rule, DOE is adopting the ECUAC test 
temperatures specified in AHRI 1340-2023.
    Regarding the test temperatures and heat rejection component power 
for WCUACs, DOE has concluded that VFDs are typically used on cooling 
tower fans to reduce cooling tower fan speed with reduced cooling load, 
and, therefore, concludes that assuming the presence of cooling tower 
fan VFDs is a more representative basis for determining the WCUAC EWTs 
and tower fan and pump power rate or ``TFPPR'' adders. Additionally, 
DOE has concluded that the updates to the approach in AHRI 1340-2023 
(i.e., updated WCUAC test temperatures and updated TFPPR approach) are 
generally consistent with the approach proposed in the August 2023 TP 
NOPR, but with more representative technical details. Further, DOE 
concludes that adopting the updated WCUAC test temperatures (and, thus, 
generally, the updated approach for developing WCUAC test temperatures 
and TFPPR values that assumes cooling tower fan VFDs) is consistent 
with comments from Carrier that included these updated temperatures.
    However, DOE is aware of three issues in the WCUAC heat rejection 
components power adders (referred to in AHRI 1340-2023 as the TFPPR) 
used in Table 7 to AHRI 1340-2023. The first issue is a mismatch 
between how the TFPPR values were developed and how they were 
implemented in AHRI 1340-2023. Specifically, the TFPPR values in Table 
7 to AHRI 1340-2023 were determined based on the full-load cooling 
capacity; therefore, the TFPPR value for each bin was intended to be 
multiplied by the full-load capacity. However, the approach implemented 
in AHRI 1340-2023 is inconsistent with these values--specifically, 
equations 8, 10, 11, and 13 specify to multiply the TFPPR by the 
cooling capacity determined for the test(s) performed for a given 
cooling bin. Because part-load cooling capacities are lower than full-
load cooling capacities, multiplying the TFPPR value for a part-load 
cooling bin by the part-load capacity for that bin results in an 
unrepresentatively low tower fan and pump power calculated for the bin. 
To resolve this issue, DOE has concluded that the values should instead 
be based on the target cooling capacity for each part-load cooling bin, 
which aligns with the approach in equations 8, 10, 11, and 13 of AHRI 
1340-2023 (i.e., multiplying the TFPPR values by the measured cooling 
capacity for each bin).
    The second issue is that the full-load cooling tower fan power was 
developed without consideration of the cooling tower fan motor 
efficiency; therefore, the calculation reflected a fan motor efficiency 
of 100 percent. Because 100 percent is a physically impossible motor 
efficiency (and, therefore, underestimates the amount of power a fan 
motor consumes), DOE has concluded that the TFPPR values should include 
a more representative (i.e., lower) full-load fan motor efficiency.
    The third issue is that the TFPPR values in AHRI 1340-2023 are 
based on an unrepresentatively low fan power at low loads. 
Specifically, the fan power was assumed to decrease cubically with 
decreasing cooling load.\19\ However, this assumption does not account 
for VFD, motor, and transmission losses which do not decrease cubically 
with decreasing cooling load. At low cooling load (e.g., for the D 
bin), this significantly underestimates cooling tower fan power because 
the VFD, motor, and transmission losses are underestimated. DOE has 
concluded that a more representative approach would be to account for 
the VFD, motor, and transmission losses when developing the 
relationship between cooling tower fan power and load. Accounting for 
these losses impacts the TFPPR values for the B, C, and D part-load 
bins.
---------------------------------------------------------------------------

    \19\ The theoretical fan laws indicate that fan power decreases 
cubically with decreasing fan speed. It was assumed that cooling 
tower fan speed is proportional to cooling load (i.e., heat to be 
rejected in the cooling tower), and, therefore, that cooling tower 
fan power decreases cubically with decreasing cooling load.
---------------------------------------------------------------------------

    Corrected TFPPR values that address these three issues with the 
values published in AHRI 1340-2023 are shown in Table III-5. DOE 
understands that the AHRI Commercial Unitary STC also plans to address 
the aforementioned issues with the TFPPR values that were published in 
AHRI 1340-2023. DOE expects that AHRI will consider including the 
corrected TFPPR values shown in Table III-5 and adopted in this final 
rule in a future version of AHRI 1340.
[GRAPHIC] [TIFF OMITTED] TR20MY24.132

    For the reasons discussed in detail in the previous paragraphs, DOE 
has concluded that the updated TFPPR values shown in Table III-5 are 
generally consistent with the approach proposed in the August 2023 TP 
NOPR, but that the corrected TFPPR values provide a more representative 
accounting of WCUAC heat rejection component power than the values 
published in AHRI 1340-2023 or the AHRI 1340-202X Draft.
    For these reasons, DOE is adopting the updated WCUAC IVEC test 
temperatures for IVEC in AHRI 1340-2023 and the TFPPR approach in AHRI 
1340-2023 as modified by the revised TFPPR values shown in Table III-5.
4. IVHE for Colder Climates
    As discussed in the August 2023 TP NOPR (see 88 FR 56392, 56416 
(August 17, 2023)), it is likely that in the future manufacturers will 
develop CUHPs that

[[Page 44007]]

are designed for operation in colder climates, and correspondingly that 
the market for CUHPs in colder climates is expected to grow. Because 
the IVHE metric is based on the US national average climate across all 
US climate zones, the lowest bin temperature for calculating IVHE is 
15.9 [deg]F, and a small fraction of heating hours are at colder 
temperatures (i.e., 19 percent of heating hours are in a load bin with 
a temperature colder than 32 [deg]F, and less than 1 percent of heating 
hours are in a load bin with a temperature colder than 17 [deg]F).
    As a result, the AHRI 1340-202X Draft includes provisions that are 
distinct from the provisions used for IVHE, including weighting factors 
and temperature bins, for calculating a colder climate-specific IVHE 
metric, designated as IVHEC. Specifically, IVHEC 
was developed using the same building heating analysis that was used to 
develop IVHE (as discussed in section III.D.2 of this final rule), but 
the IVHEC weighting factors and load bins were developed 
using the results for climates zones 5 and above (i.e., climate zone 5 
as well as all climate zones colder than climate zone 5), weighted by 
the share of the U.S. population in each of those climate zones. The 
use of only climate zones 5 and colder for IVHEC results in 
the following, compared to IVHE: lower outdoor dry-bulb temperature for 
each load bin, more heating season hours in all load bins, and a higher 
heating season building load. Specifically, for IVHEC, 56 
percent of heating hours are in a load bin with a temperature colder 
than 32 [deg]F, and 12 percent of heating hours are in a load bin with 
a temperature colder than 17 [deg]F. Further, because the defrost 
degradation coefficients specified in appendix C of the ACUAC and ACUHP 
Working Group TP Term Sheet depend on the outdoor temperature for each 
load bin (and IVHEC has colder bin temperatures than IVHE), 
the AHRI 1340-202X Draft also specifies separate defrost degradation 
coefficients for calculating IVHEC. In the August 2023 TP 
NOPR, DOE proposed to adopt provisions for determining the 
IVHEC metric in appendix A1 via reference to the AHRI 1340-
202X Draft and to allow for optional representations of 
IVHEC for CUHPs. 88 FR 56392, 56416 (August 17, 2023).
    In response to the August 2023 TP NOPR, NEEA and NYSERDA supported 
DOE's proposal to include in the test procedure and allow optional 
representations of the colder climate IVHEC. (NEEA, No. 16 
at pp. 2-3; NYSERDA, No. 13 at p. 2)
    Given the potential for the development of CUHPs designed for 
operation in colder climates and the expected increased number of 
shipments of CUHPs into colder climates, DOE recognizes the utility in 
having CUHP ratings for a separate IVHE metric that is specific to 
colder climates. AHRI 1340-2023 includes provisions for determining 
IVHEC that are generally consistent with the AHRI 1340-202X 
Draft, with the additional specificity discussed in section III.E.8 of 
this final rule. Correspondingly, DOE has concluded that the 
IVHEC metric as specified in AHRI 1340-2023 (including the 
minor updates in the published AHRI 1340-2023 that provide additional 
specificity as discussed in section III.E.8 of this document) is more 
representative of field conditions for CUHPs installed in colder US 
climates. Therefore, DOE is adopting provisions for determining the 
IVHEC metric in appendix A1 via reference to AHRI 1340-2023 
and allowing for optional representations of IVHEC for 
CUHPs. Specifically, DOE is amending the test procedure so that IVHE 
will be the regulated heating metric when testing to appendix A1; 
therefore, should DOE adopt amended standards for CUHPs denominated in 
terms of IVEC and IVHE, all CUHPs will be required to certify 
compliance with IVHE standards, and additional representations of 
IVHEC will be optional.
5. Test Conditions Used for Current Metrics in Appendix A
    AHRI 340/360-2022 designates certain test conditions for test 
procedures characterized as ``standard rating tests'' and certain other 
test conditions for test procedures characterized as ``performance 
operating tests.'' The ``standard rating tests'' are used for 
determining representations of cooling capacity, heating capacity, and 
cooling and heating efficiencies. The ``performance operating tests'' 
evaluate other operating conditions, such as ``maximum operating 
conditions'' (see section 8 of AHRI 340/360-2022). Specifically, Table 
6 of AHRI 340/360-2022 specifies test conditions for standard rating 
and performance operating tests for CUACs and CUHPs. The relevant 
conditions for EER and IEER cooling tests are those referred to as 
``standard rating conditions'' in AHRI 340/360-2022.
    To clarify this distinction and consistent with its proposal to 
adopt AHRI 340/360-2022 in appendix A, DOE proposed in the August 2023 
TP NOPR to specify explicitly in section 3 of appendix A that the 
cooling test conditions used for representations as required under the 
DOE regulations would be: (1) for equipment subject to standards in 
terms of EER, the ``Standard Rating Conditions, Cooling'' conditions 
specified in Table 6 of AHRI 340/360-2022; and (2) for equipment 
subject to standards in terms of IEER, the ``Standard Rating 
Conditions, Cooling'' and ``Standard Rating Part-Load Conditions 
(IEER)'' conditions specified in Table 6 of AHRI 340/360-2022. 88 FR 
56392, 56412 (August 17, 2023).
    For heating mode tests of CUHPs, Table 6 of AHRI 340/360-2022 
includes ``Standard Rating Conditions'' for both a ``High Temperature 
Steady-state Test for Heating'' and a ``Low Temperature Steady-state 
Test for Heating'' (conducted at 47 [deg]F and 17 [deg]F outdoor air 
dry-bulb temperatures, respectively). To clarify which conditions are 
applicable for representations as required under the DOE regulations 
and consistent with its proposal to adopt AHRI 340/360-2022 in appendix 
A, DOE proposed to specify explicitly in section 3 of appendix A that 
the heating test conditions used for compliance are the ``Standard 
Rating Conditions (High Temperature Steady-state Heating)'' conditions 
specified in Table 6 of AHRI 340/360-2022. Further, DOE proposed to 
include the low-temperature (i.e., 17 [deg]F) heating test condition 
specified in Table 6 of AHRI 340/360-2022 (referred to as ``Low 
Temperature Steady-state Heating'') and specify in section 3 of 
appendix A that representations of COP at this low-temperature heating 
condition are optional. 88 FR 56392, 56412 (August 17, 2023).
    DOE did not receive any comments in response to these proposals. 
Therefore, DOE is adopting the specification of the relevant test 
conditions in AHRI 340/360-2022 in appendix A as proposed. These 
amendments in appendix A are consistent with the test requirements 
referenced in the latest version of ASHRAE Standard 90.1.
6. Test Conditions Used for New Metrics in Appendix A1
    Consistent with DOE's proposal to adopt the AHRI 1340-202X Draft 
for determining IVEC and IVHE, as discussed more fully in the August 
2023 TP NOPR, DOE proposed to specify in section 3 of the proposed 
appendix A1 which test conditions in the AHRI 1340-202X Draft would be 
required and optional for rating to IVEC and IVHE. 88 FR 56392, 56412-
56413 (August 17, 2023). DOE also proposed to include provisions for 
optional representations of the full-load efficiency metrics, EER2, 
COP247, COP217, and COP25, and 
specified the test conditions required for these optional 
representations. Id. DOE did not receive any comments regarding

[[Page 44008]]

the proposed approach for specifying the required and optional test 
conditions. The test conditions in AHRI 1340-2023 align with those in 
the AHRI 1340-202X Draft except for certain test conditions for ECUACs 
and WCUACs, which are discussed in section III.E.3 of this final rule. 
Therefore, DOE is adopting the specification of test conditions in 
appendix A1 as proposed, referencing the corresponding test conditions 
in the published AHRI 1340-2023.
7. Provisions Introduced in the AHRI 1340-202X Draft
    The AHRI 1340-202X Draft proposed for adoption in the August 2023 
TP NOPR includes several provisions regarding the new IVEC and IVHE 
metrics that are not included in the ACUAC and ACUHP Working Group TP 
Term Sheet. DOE notes that the ACUAC and ACUHP Working Group TP Term 
Sheet includes provisions to allow changes to the recommendations in 
the term sheet if mistakes in the original recommendations are 
identified through further analysis or discussion between stakeholders. 
(See EERE-2022-BT-STD-0015-0065, Recommendations #2, #8, #11) Further, 
the AHRI 1340-202X Draft includes a number of additional test 
provisions that arose as a result of discussions between many 
interested stakeholders participating in the AHRI Commercial Unitary 
STC and that DOE has concluded are consistent with the intent of the 
ACUAC and ACUHP Working Group TP Term Sheet but provide additional 
guidance for determining IVEC and IVHE. DOE included discussion of 
provisions regarding the topics discussed in the following sub-sections 
in the August 2023 TP NOPR and proposed to adopt the provisions in the 
AHRI 1340-202X Draft regarding all of these topics. 88 FR 56392, 56416-
56419 (August 17, 2023). DOE did not receive comment regarding the 
provisions in the AHRI 1340-202X Draft addressing these topics, and 
these provisions are also included in the published AHRI 1340-2023, 
consistent with DOE's proposals in the August 2023 TP NOPR. As 
discussed, DOE is adopting AHRI 1340-2023 for determining IVEC and IVHE 
in appendix A1, including these additional provisions not specified in 
the ACUAC and ACUHP Working Group TP Term Sheet, consistent with 
proposals in the August 2023 TP NOPR. The following sections discuss 
these provisions in further detail.
a. Cooling Weighting Factors Adjustment
    Subsequent to the development of the ACUAC and ACUHP Working Group 
TP Term Sheet, additional analysis of the building models used to 
develop the weighting factors for the IVEC metric indicated that the 
recommended weighting hours included in the ACUAC and ACUHP Working 
Group TP Term Sheet are incorrect. Specifically, the weighting hour 
factors in the ACUAC and ACUHP Working Group TP Term Sheet over-
represent mechanical-only cooling hours and underrepresent economizer-
only and integrated-economizer hours for all IVEC load bins. DOE 
presented corrected weighting factors during the ACUAC and ACUHP 
standards negotiations, and no concerns were raised. (See EERE-2022-BT-
STD-0015-0078 at p. 8) These corrected IVEC weighting factors were 
included in the AHRI 1340-202X Draft and remain the same in AHRI 1340-
2023. DOE is adopting AHRI 1340-2023 for determining IVEC and IVHE in 
appendix A1, including these updated IVEC weighting factors.
b. ESP Testing Target Calculation
    Recommendation #12 of the ACUAC and ACUHP Working Group TP Term 
Sheet includes an equation for determining adjusted ESP for cooling or 
heating tests that use an airflow that differs from the full-load 
cooling airflow. However, the equation specified in Recommendation #12 
is missing a term for the full-load ESP. This equation was corrected in 
the AHRI 1340-202X Draft and remains the same in AHRI 1340-2023. DOE is 
adopting AHRI 1340-2023 for determining IVEC and IVHE in appendix A1, 
including this corrected equation for determining adjusted ESP.
c. Test Instructions for Splitting ESP Between Return and Supply Duct
    As discussed previously, Recommendation #12 of the ACUAC and ACUHP 
Working Group TP Term Sheet specifies that ESP shall be split between 
return and supply ducts during testing, such that 25 percent of the ESP 
is applied in the return ductwork. However, the ACUAC and ACUHP Working 
Group TP Term Sheet does not contain explicit test se-tup instructions 
specifying how to achieve the split in ESP between return and supply 
ductwork. Section E11 in appendix E of the AHRI 1340-202X Draft and 
section E11 in appendix E of AHRI 1340-2023 include more detailed 
instructions regarding the duct and pressure measurement set-up, the 
measurement and adjustment of the return static pressure, and the 
restriction devices that can be used in the return ductwork to achieve 
the required split of between 20 and 25 percent of the total ESP 
applied to the return ductwork. The AHRI 1340-202X Draft and AHRI 1340-
2023 also include the same test instructions for cases in which the ESP 
split is not achieved in the first test, as well as any exceptions to 
the specified tolerance requirement. DOE has concluded that these 
additional instructions provide a more consistent measurement of ESP 
and are aligned with the intent of Recommendation #12 of the ACUAC and 
ACUHP Working Group TP Term Sheet. Therefore, DOE is adopting these 
provisions of AHRI 1340-2023 for determining IVEC and IVHE.
d. Default Fan Power and Maximum Pressure Drop for Coil-Only Systems
    DOE's current test procedure for CUACs and CUHPs references ANSI/
AHRI 340/360-2007, and section 6.1 of that test standard specifies 
default fan power and corresponding capacity adjustment for ACUACs, 
ACUHPs, ECUACs, and WCUACs with a coil-only configuration (i.e., 
without an integral indoor fan). Specifically, ANSI/AHRI 340/360-2007 
requires that an indoor fan power of 365 Watts (``W'') per 1,000 
standard cubic feet per minute (``scfm'') be added to power input for 
coil-only units and that the corresponding heat addition (i.e., 1,250 
Btu/h per 1,000 scfm) be subtracted from measured cooling capacity (and 
added to measured heating capacity), regardless of the capacity of the 
unit under test and regardless of full-load or part-load test 
conditions.
    Section 6.1.1.6 of AHRI 340/360-2022 has the same requirement as 
ANSI/AHRI 340/360-2007 regarding default fan power and capacity 
adjustment of coil-only systems. Additionally, both section 6.1.3.2(d) 
of ANSI/AHRI 340/360-2007 and section 6.1.3.3.4 of AHRI 340/360-2022 
specify that for coil-only systems, the pressure drop across the indoor 
assembly shall not exceed 0.30 in. H2O for the full-load 
cooling test. If the measured pressure drop exceeds that value, then 
the industry test standards specify that the indoor airflow rate be 
reduced such that the measured pressure drop does not exceed the 
specified maximum pressure drop.
    The AHRI 1340-202X Draft included different requirements for 
testing coil-only units as compared to ANSI/AHRI 340/360-2007 and AHRI 
340/360-2022. First, section 5.17.4 of the AHRI 1340-202X Draft 
includes a higher maximum pressure drop across the indoor assembly of 
1.0 in. H2O when testing

[[Page 44009]]

coil-only units, as compared to the maximum pressure drop of 0.3 in. 
H2O specified in ANSI/AHRI 340/360-2007 and AHRI 340/360-
2022. Second, section 6.2.4.2 of the AHRI 1340-202X Draft includes 
higher default fan power values than specified in ANSI/AHRI 340/360-
2007 and AHRI 340/360-2022; these values were updated to reflect the 
higher ESP requirements used for IVEC and IVHE. Because the ACUAC and 
ACUHP Working Group TP Term Sheet and the AHRI 1340-202X Draft specify 
ESP requirements that vary by capacity bin, section 6.2.4.2 of the AHRI 
1340-202X Draft specifies different default fan power adders and 
capacity adjustments for each capacity bin, developed based on fan 
power needed to overcome the ESP requirement for each bin. DOE proposed 
in the August 2023 TP NOPR to adopt the default fan power adders and 
capacity adjustments included in the AHRI 1340-202X Draft in appendix 
A1. 88 FR 56392, 56417 (August 17, 2023).
    Lastly, while ANSI/AHRI 340/360-2007 and AHRI 340/360-2022 specify 
a single default fan power adder (and corresponding capacity 
adjustment) to be used for all tests, the AHRI 1340-202X Draft included 
separate default fan power adders and capacity adjustments for full-
load tests and part-load tests (i.e., tests conducted at an airflow 
lower than the full-load cooling airflow) to reflect that fan power 
does not decrease linearly with airflow (i.e., reducing airflow in 
part-load operation would reduce fan power in field operation by more 
than would be calculated using a single power adder that is normalized 
by airflow). These part-load fan power adders and capacity adjustments 
were developed assuming a part-load airflow that is 67 percent of the 
full-load airflow. The AHRI 1340-202X Draft does not specify what 
values to use if the part-load airflow is between 67 and 100 percent of 
the full-load airflow. Alongside proposing to adopt the fan power 
adders specified in the AHRI 1340-202X Draft in the August 2023 TP 
NOPR, DOE proposed to adopt a linear interpolation approach in appendix 
A1 in the case where the part-load airflow for coil-only CUACs and 
CUHPs specified by a manufacturer for a test is between 67 and 100 
percent of the full-load airflow, which would specify how to calculate 
the default fan power coefficient and capacity adjustment in such 
cases. 88 FR 56392, 56417 (August 17, 2023). The proposed approach is 
consistent with the approach adopted for the residential CAC/HP test 
procedure.\20\
---------------------------------------------------------------------------

    \20\ The CAC/HP test procedure final rule was published in the 
Federal Register on October 25, 2022, and can be found at 87 FR 
64550.
---------------------------------------------------------------------------

    Consistent with the basis of part-load values in the AHRI 1340-202X 
Draft on 67 percent of full-load cooling airflow, DOE also proposed in 
the August 2023 TP NOPR to clarify that for tests in which the 
manufacturer-specified airflow is less than the full-load cooling 
airflow, the target airflow for the test must be the higher of: (1) the 
manufacturer-specified airflow for the test; or (2) 67 percent of the 
airflow measured for the full-load cooling test. 88 FR 56392, 56417 
(August 17, 2023).
    AHRI 1340-2023 includes provisions consistent with those DOE 
proposed to adopt for testing coil-only units in the August 2023 TP 
NOPR. Id. Specifically, the already discussed maximum pressure drop and 
capacity and fan power adjustments included in sections 5.17.4 and 
6.2.4.2 of the AHRI 1340-202X Draft are included in sections 5.17.2 and 
6.2.4.3 of AHRI 1340-2023. Additionally, AHRI 1340-2023 includes 
provisions consistent with DOE's proposals regarding issues for testing 
coil-only units not addressed in the AHRI 1340-202X Draft. 
Specifically, section 6.2.4.2 of AHRI 1340-2023 includes the linear 
interpolation method to address cases in which the part-load airflow 
specified by a manufacturer for a test is between 67 and 100 percent of 
the full-load airflow. Further, section 5.18.4.2 of AHRI 1340-2023 
includes the clarification regarding which target airflow should be 
used for tests in which the manufacturer-specified airflow is less than 
the full-load cooling airflow.
    Accordingly, DOE has concluded that the coil-only test procedure in 
AHRI 1340-2023 aligns with the approach proposed in the August 2023 TP 
NOPR and represents industry consensus on the most appropriate and 
representative way to test and determine the IVEC and IVHE of coil-only 
systems. Therefore, DOE is adopting these provisions of AHRI 1340-2023 
for determining IVEC and IVHE for coil-only units.
e. Component Power Measurement
    Section E10 of the AHRI 1340-202X Draft and AHRI 1340-2023 include 
additional instruction regarding how the total unit, indoor fan, 
controls, compressor, condenser section, and crankcase heat power 
should be measured and accounted for during a test. This includes 
details that were not included in the ACUAC and ACUHP Working Group TP 
Term Sheet, as well as updates to address issues such as unique model 
designs and power meter precision that were identified after the term 
sheet was completed. For example, although the ACUAC and ACUHP Working 
Group TP Term Sheet specified that controls power be determined by 
subtracting all other power measurements from the total unit power, 
sections E10.1 and E10.2 of both the AHRI 1340-202X Draft and AHRI 
1340-2023 require that controls power be measured. This is because 
controls power is a much smaller value than power consumed by other 
components of a CUAC or CUHP and, thus, is more accurately determined 
by measuring directly with a power meter of sufficient precision. 
Section E10.2 of both the AHRI 1340-202X Draft and AHRI 1340-2023 also 
allow for determination of compressor and condenser section power by 
measurement together or by subtraction from total power (i.e., separate 
power measurement of power consumed by the compressor and condenser 
section is not required). These provisions address cases in which 
unique wiring of certain models may make separate measurement of 
compressor and condenser section power very difficult or impossible, in 
addition to cases in which the laboratory does not have enough power 
meters to measure all components separately. Section E10.3 of both the 
AHRI 1340-202X Draft and AHRI 1340-2023 also provide an equation for 
calculating default value(s) for crankcase heater power to address the 
case in which a manufacturer does not specify crankcase heater 
wattage.\21\ Because DOE has concluded that these provisions will 
provide more repeatable and representative test results, DOE is 
adopting AHRI 1340-2023 for determining IVEC and IVHE in appendix A1, 
including these provisions for component power measurement.
---------------------------------------------------------------------------

    \21\ As discussed, Recommendation #13 of the ACUAC and ACUHP 
Working Group TP Term Sheet requires that manufacturers certify 
crankcase heater wattage for each heater. DOE is not adopting 
amendments to certification requirements in this rulemaking, and 
will instead address certification requirements in a separate 
rulemaking for certification, compliance, and enforcement.
---------------------------------------------------------------------------

f. Non-Standard Low-Static Indoor Fan Motors
    As discussed in section III.D.1 of this document, DOE is adopting 
higher ESPs recommended by the Working Group and included in AHRI 1340-
2023 in the appendix A1 Federal test procedure for CUACs and CUHPs. 
However, individual models of CUACs and CUHPs with indoor fan motors 
intended

[[Page 44010]]

for installation in applications with a low ESP may not be able to 
operate at the adopted full-load ESP requirements at the full-load 
indoor rated airflow. To address this situation, section 3.25 of the 
AHRI 1340-202X Draft and section 3.2.30 of AHRI 1340-2023 both define 
``non-standard low-static indoor fan motors'' as motors which cannot 
maintain ESP as high as specified in the test procedure when operating 
at the full-load rated indoor airflow and that are distributed in 
commerce as part of an individual model within the same basic model 
that is distributed in commerce with a different motor specified for 
testing that can maintain the required ESP. Section 5.19.3.3 of the 
AHRI 1340-202X Draft and section 5.19.3.3 of AHRI 1340-2023 include the 
same test provisions for CUACs and CUHPs with non-standard low-static 
indoor fan motors that cannot reach the ESP within tolerance during 
testing, which require using the maximum available fan speed that does 
not overload the motor or motor drive, adjusting the airflow-measuring 
apparatus to maintain airflow within tolerance, and operating with an 
ESP as close as possible to the minimum ESP requirements for testing. 
This approach is consistent with the industry test standard referenced 
by the DOE test procedure for DX-DOASes (AHRI 920-2020).
    As discussed in section III.F.5.a of this document, DOE is 
clarifying that representations for a CUAC or CUHP basic model must be 
based on the least efficient individual model(s) distributed in 
commerce within the basic model (with the exception specified in 10 CFR 
429.43(a)(3)(vi)(A) for certain individual models with the components 
listed in table 6 to 10 CFR 429.43(a)(3)). DOE has concluded that the 
combination of: (1) the provisions in AHRI 1340-2023 for testing models 
with ``non-standard low-static indoor fan motors'' with (2) the 
requirement that basic models be rated based on the least efficient 
individual model (with certain exceptions, as discussed) provides an 
appropriate approach for handling CUAC and CUHP models with these 
motors--if an individual model with a non-standard low-static indoor 
fan motor is tested, the test will be conducted at an indoor airflow 
representative for that model. But because testing at the rated airflow 
for such an individual model will result in testing at an ESP lower 
than the requirement and, thus, a lower indoor fan power, the 
representations for that basic model will be required to be based on an 
individual model with an indoor fan motor that can achieve the ESP 
requirements at the rated airflow. Consistent with the adoption of AHRI 
340/360-2023 in appendix A1, DOE is not deviating from the provisions 
for testing models with non-standard low-static indoor fan motors.
g. IVHE Equations
    Section 6.3 of the AHRI 1340-202X Draft and section 6.3 of AHRI 
1340-2023 both include several changes regarding the heating metric 
equations that differ from the provisions in appendix C of the ACUAC 
and ACUHP Working Group TP Term Sheet. DOE has concluded that these 
updated IVHE equations, described in the following paragraphs, provide 
for a more accurate calculation of IVHE. Further, Recommendation #9 of 
the ACUAC and ACUHP Working Group TP Term Sheet states that the 
equations in appendix C of the term sheet are subject to quality 
control checking (``QC'') for errors, with the intent remaining the 
same as voted on. DOE has concluded that the discussed deviations in 
the AHRI 1340-202X Draft and the published AHRI 1340-2023 hold the same 
intent of the recommendations set forth in the ACUAC and ACUHP Working 
Group TP Term Sheet. Therefore, DOE is adopting the provisions of AHRI 
1340-2023 for determining IVHE in appendix A1, including the updated 
equations discussed in this section.
    1. Removal of the cut-out factor from certain equations: Appendix C 
of the ACUAC and ACUHP Working Group TP Term Sheet includes a cut-out 
factor in IVHE calculations to reflect the dependence of unit 
performance on whether compressors are cut-out at a given bin 
temperature. However, the cut-out factor was inadvertently included in 
certain equations in appendix C of the ACUAC and ACUHP Working Group TP 
Term Sheet where it should not apply (i.e., equations to determine unit 
performance that should not be impacted by the fraction of time in 
which compressors are cut out). Therefore, in the AHRI 1340-202X Draft 
and AHRI 1340-2023, the cut-out factor is removed from those equations 
where it was incorrectly applied in the ACUAC and ACUHP Working Group 
TP Term Sheet. For all CUHPs that DOE is aware of on the market today, 
the cut-in and cut-out temperatures are less than the temperature of 
the lowest load bin. As such, the cut-out factor only applies when the 
unit is operating at full-load capacity and does not affect the 
calculation of IVHE.
    2. Accounting for auxiliary heat when compressors are cut out: When 
compressors are cut out, auxiliary heat would operate to meet the 
building load. This auxiliary heat operation is addressed in section b 
of appendix C of the ACUAC and ACUHP Working Group TP Term Sheet (i.e., 
when building load exceeds the highest stage unit heating capacity at a 
given bin temperature), but was inadvertently excluded in sections c 
and d of appendix C of the ACUAC and ACUHP Working Group TP Term Sheet 
(i.e., when building load is between capacities of a unit tested with 
multiple heating stages, or when building load is less than the 
capacity for the lowest tested compressor stage). Therefore, the AHRI 
1340-202X Draft and AHRI 1340-2023 include corrections in these cases 
so that auxiliary heat demand is applied to meet building load in all 
cases in which compressors are cut out.
    3. Fan power applied in auxiliary heat-only mode: In appendix C of 
the Term Sheet, the equations do not subtract the heat gain in the 
indoor airstream from the indoor fan (i.e., ``fan heat'') from the 
auxiliary heat demand. The AHRI 1340-202X Draft and AHRI 1340-2023 
address this issue by subtracting fan heat from auxiliary heat demand. 
Additionally, sections c and d of appendix C of the ACUAC and ACUHP 
Working Group TP Term Sheet assume that the fan would be either cycling 
between airflows when cycling between stages of compression or 
operating at the lowest-measured indoor airflow for any cooling or 
heating test when cycling on and off at the lowest stage of 
compression; however, the indoor fan would likely be operating at the 
airflow corresponding to the full-load heating test when operating in 
auxiliary heat mode. The AHRI 1340-202X Draft and AHRI 1340-2023 
address this by applying fan power from the full-load heating test for 
auxiliary heat-only mode. However, DOE notes that because both fan heat 
and auxiliary heat apply heat to the indoor airstream with the same 
efficiency (i.e., COP of 1), the airflow assumed for auxiliary heat-
only mode does not impact results, as the fan heat resulting from an 
increase in fan power reduces the auxiliary heat needed to meet the 
building load by the same amount, resulting in no net change to 
calculated IVHE.
    4. Interpolation for variable-speed compressor systems: When 
building load is between capacities of a unit tested with multiple 
heating stages, section c of appendix C of the Term Sheet includes a 
separate method for interpolating between stages for variable-speed 
compressor systems (i.e., a method that interpolates capacity divided 
by power) from the method for all other units (i.e., a method that 
linearly interpolates power). As part of

[[Page 44011]]

development of the AHRI 1340-202X Draft, it was determined that there 
were insufficient data to support a separate interpolation method for 
variable-speed compressor systems, and, therefore, the AHRI 1340-202X 
Draft and AHRI 1340-2023 apply the same linear interpolation method 
based on power for all units. The linear interpolation method for 
variable-speed compressor systems included in the AHRI 1340-202X Draft 
is also maintained in AHRI 1340-2023.
    5. Compressor operating levels for heating tests: Recommendation #9 
of the Term Sheet includes details on the required and optional tests 
based on configuration of the system (i.e., single-stage, two or more 
stages, and variable-capacity). Required tests include a test at 
``high'' operating level at 17 [deg]F and 47 [deg]F; optional tests 
include tests at low and intermediate operating levels at 17 [deg]F and 
47 [deg]F, as well as high and ``boost'' operating levels at 5 [deg]F. 
For variable-capacity systems, the Term Sheet specifies that the high 
speed and low speed at each temperature should be the normal maximum 
and minimum for each ambient temperature. The AHRI 1340-202X Draft 
includes additional explanation of which compressor speeds correspond 
to the low, medium, high, and boost designations at each test 
temperature. AHRI 1340-2023 maintains the explanations included in AHRI 
1340-202X Draft and includes further explanation of the compressor 
operating levels, as discussed in section III.E.8.b of this final rule.
    In the August 2023 TP NOPR, DOE tentatively concluded that these 
updated IVHE equations as described in the preceding paragraphs would 
provide for a more accurate calculation of IVHE. 88 FR 56392, 56419 
(August 17, 2023). Further, Recommendation #9 of the ACUAC and ACUHP 
Working Group TP Term Sheet states that the equations in appendix C of 
the Term Sheet are subject to quality control checking (``QC'') for 
errors with the intent remaining the same as voted on. In the August 
2023 TP NOPR, DOE tentatively concluded that the discussed deviations 
in the AHRI 1340-202X Draft hold the same intent of the recommendations 
set forth in the ACUAC and ACUHP Working Group TP Term Sheet. 
Therefore, DOE proposed to adopt the provisions of AHRI 1340-202X Draft 
for determining IVHE in appendix A1, including the updated equations 
discussed in this section. 88 FR 56392, 56418-56419 (August 17, 2023).
    AHRI 1340-2023 includes the largely the same provisions as AHRI 
1340-202X Draft for determining IVHE. Any differences between the 
provisions in AHRI 1340-202X Draft and AHRI 1340-2023 are discussed in 
section III.E.8 of this final rule. Therefore, DOE has concluded that 
that the updated IVHE equations in AHRI 1340-2023, as described in the 
preceding paragraphs, would provide for a more accurate calculation of 
IVHE than the equations in the ACUAC and ACUHP Working Group TP Term 
Sheet, and that the discussed deviations hold the same intent as the 
recommendations set forth in the ACUAC and ACUHP Working Group TP Term 
Sheet. Therefore, DOE is adopting in appendix A1 the approach for 
determining IVHE from AHRI 1340-2023.
    DOE notes that appendix C of the ACUAC and ACUHP Working Group TP 
Term Sheet includes a provision that ``additional provisions, still TBD 
would apply for variable-speed compressors for which pairs of full-
speed or minimum-speed tests are not run at the same speed.'' (See 
EERE-2022-BT-STD-0015-0065 at p. 14) The AHRI 1340-202X Draft does not 
include any provisions allowing for determination of capacity for a bin 
by interpolating between tests conducted at different compressor 
operating levels. In the August 2023 TP NOPR, DOE tentatively concluded 
that this approach is appropriate and that calculating IVHE with 
results from multiple tests at each compressor operating level would 
provide representative ratings for manufacturers that choose to include 
performance at operating levels beyond the required high operating 
level tests at 47 and 17 [deg]F in their representations of IVHE. 88 FR 
56392, 56419 (August 17, 2023). AHRI 1340-2023 also includes no such 
provisions allowing interpolation between tests conducted at different 
compressor operating levels. Therefore, DOE maintains its tentative 
conclusion from the August 2023 TP NOPR and is adopting the approach 
for determining IVHE from AHRI 1340-2023 unchanged.
8. Heating Test Provisions Not Included in the AHRI 1340-202X Draft
a. General
    As discussed in the August 2023 TP NOPR (88 FR 56392, 56418-56419 
(August 17, 2023)) and section III.E.7.g of this final rule, the AHRI 
1340-202X Draft includes conditions for heating tests and calculations 
for the IVHE, IVHEC, and COP2 metrics that DOE proposed to 
adopt in the August 2023 TP NOPR. AHRI 1340-2023 includes several 
updates to the heating test provisions as compared to the AHRI 1340-
202X Draft. The following sections describe these updates and what DOE 
is adopting in this final rule.
b. Definitions of Heating Operating Levels
    Table 26 to AHRI 1340-202X Draft and section 6.3.5 of AHRI 1340-
202X Draft specify the heating operating levels to use and the 
requirements for each, but do not make clear the parameters included in 
defining an operating level. Section 3.2.31 of AHRI 1340-2023 includes 
definitions for all heating operating levels, as well as a general 
definition of ``operating level.'' Section 3.2.31.6 defines ``operating 
level'' as being determined by the number of compressors operating, the 
modulation level of each operating compressor, and the indoor fan 
speed. The definition indicates that the modulation level of a single 
compressor is determined by the speed, duty cycle, vapor injection 
setting, and state of any other operating parameters that affect the 
continuous capacity of the compressor at a single set of operating 
conditions.
    DOE is adopting these AHRI 1340-2023 operating level definitions in 
the DOE test procedure for CUACs and CUHPs, because DOE has concluded 
that they provide appropriate clarity on how to determine the operating 
levels to be used for heating tests and are substantively consistent 
with the AHRI 1340-202X Draft, which DOE proposed to adopt in the 
August 2023 TP NOPR. The one exception is the definition for the 
``boost2 heating operating level,'' which is discussed in section 
III.E.8.c of this final rule.
c. Boost2 Heating Operating Level and COP25
    The AHRI 1340-202X Draft includes low, medium, high, and boost 
heating operating levels, with boost being the operating level with the 
highest heating capacity. The boost operating level uses the maximum 
compressor operating capacity that is allowed by the controls at 17 
[deg]F, and the airflow that is allowed by the controls at 17 [deg]F 
when operating at the chosen compressor operating capacity. AHRI 1340-
2023 includes all the same heating operating levels as the AHRI 1340-
202X Draft, plus a boost2 heating operating level. AHRI 1340-2023 
defines the ``boost2 operating level'' as an operating level allowed by 
the controls at 5 [deg]F outdoor dry-bulb temperature with a capacity 
at 5 [deg]F outdoor dry-bulb temperature that is greater than the 
capacity of the boost heating operating level at 5 [deg]F outdoor dry-
bulb temperature and less than or equal to the maximum capacity allowed 
by the controls at 5 [deg]F outdoor dry-bulb temperature.

[[Page 44012]]

    For units with a boost operating level, AHRI 1340-2023 specifies 
representations of COP25 be based on the capacity and power 
determined at the boost or boost2 heating operating level denoted as 
the H5B or H5B2 tests in Table 23 to AHRI 1340-2023. However, AHRI 
1340-2023 does not allow the H5B2 test to be used in the calculation of 
IVHE or IVHEC. As discussed in section III.E.7.g of this 
document, AHRI 1340-2023 does not include any provisions allowing for 
determination of capacity for a bin by interpolating between tests 
conducted at different compressor operating levels. Therefore, 
inclusion of results from the boost2 operating level would require at 
least two tests conducted at this operating level. Because there is no 
other test specified at a different outdoor dry-bulb temperature 
condition at this same boost2 operating level, AHRI 1340-2023 only 
allows the H5B2 test to be used to determine the capacity at 5 [deg]F 
outdoor dry-bulb temperature or COP2 at 5 [deg]F.
    DOE has determined that including a boost2 heating operating level 
allows for manufacturers to make performance representations that 
adequately reflect boosted heating performance at lower temperatures. 
DOE notes that Recommendation #9 of the ACUAC and ACUHP Working Group 
TP Term Sheet includes the following: ``Manufacturers can make 
representations of COP and capacity at any of the following 
temperatures: 5 [deg]F, 17 [deg]F, and 47 [deg]F, in accordance with 
the DOE test procedure, in addition to the IVHE metric that will be 
required for standards.'' (See EERE-2022-BT-STD-0015-0065 at p. 6) As 
mentioned in section III.E.4 of this final rule, DOE acknowledges that 
in the future manufacturers will likely develop CUHPs that are designed 
for operation in colder climates. This may include designing CUHPs that 
are capable of providing boosted heating capacity at low temperatures. 
DOE has determined that the inclusion of the boost2 heating operating 
level and the H5B2 test in AHRI 1340-2023 is consistent with the intent 
of Recommendation #9 of the Term Sheet. This will allow for 
manufacturers designing systems with boosted heating capacity at 5 
[deg]F that differs from the operating levels at higher outdoor 
temperatures to make representations of capacity and performance at 5 
[deg]F, and correspondingly provide commercial consumers interested in 
low-temperature heating performance an additional standardized metric 
to compare such performance across models. Further, DOE has concluded 
that the inclusion of the boost2 heating operating level and the H5B2 
test in AHRI 1340-2023 is generally consistent with the AHRI 1340-202X 
Draft, in that it maintains the proposed allowance for optional 
representations at 5 [deg]F, but adds additional options for 
manufacturers to determine this optional representation at the 
compressor speed most representative for a model. As discussed, testing 
at the boost2 heating operating level is optional and would not be 
required for determinations of IVHE. DOE is adopting the H5B2 test in 
its amended test procedure at appendix A1, but with two additional 
clarifying provisions not included in AHRI 1340-2023.
    First, section 6.3.14.2 of AHRI 1340-2023 specifies that for 
determining the COP25 of units with a boost operating level, 
one must use the capacity and power determined for the H5B or H5B2 
test, instead of the H5H test. These provisions indicate that optional 
COP25 representations for such units are based on a higher 
heating operating level but do not specify whether the H5B or H5B2 test 
is to be used for a unit that has both a boost heating operating level 
and a boost2 heating operating level. DOE has determined that 
additional specificity is warranted as to which test is used to 
determine optional COP25 representations--specifically, DOE 
has concluded that it should be clarified to use the highest applicable 
heating operating level to determine COP25. Therefore, DOE 
is adding the following clarification to section 5.3 of appendix A1: 
For units without a boost heating operating level and without a boost 2 
heating operating level, use capacity and power determined for the H5H 
test. For units with a boost heating operating level and without a 
boost 2 heating operating level, use capacity and power determined for 
the H5B test. For units with a boost 2 heating operating level, use 
capacity and power determined for the H5B2 test.
    Second, section 3.2.31.1 of AHRI 1340-2023 defines the ``boost 
heating operating level'' as the operating level that has the maximum 
capacity allowed by the controls at 17 [deg]F outdoor dry-bulb 
temperature, with a capacity at 17.0 [deg]F outdoor dry-bulb 
temperature that is greater than the capacity of the high heating 
operating level \22\ at 17 [deg]F. This means that there is no boost 
heating operating level if the high heating operating level is the 
heating operating level with the maximum capacity at 17 [deg]F. Section 
3.2.31.2 of AHRI 1340-2023 defines the ``boost2 heating operating 
level'' as an operating level allowed by the controls at 5 [deg]F 
outdoor dry bulb-temperature with a capacity at 5 [deg]F outdoor dry 
bulb-temperature that is greater than the capacity of the boost heating 
operating level at 5 [deg]F and less than or equal to the maximum 
capacity allowed by the controls at 5 [deg]F outdoor dry bulb-
temperature.
---------------------------------------------------------------------------

    \22\ Section 3.2.31.3 of AHRI 1340-2023 defines ``high heating 
operating level'' as the operating level with the maximum capacity 
that is allowed by the controls at 47.0 [deg]F outdoor dry-bulb 
temperature.
---------------------------------------------------------------------------

    Because the definition of the ``boost2 heating operating level'' 
relies on the capacity of the boost operating level, the definition 
implies that a model must have an operating level that meets the 
definition for the boost heating operating level in order for it to 
also have a boost2 heating operating level. This implication means that 
AHRI 1340-2023 would not allow the H5B2 test to be conducted for a 
model which has no boost heating operating level at 17 [deg]F, even if 
that model has an operating level with a capacity at 5 [deg]F that is 
greater than the capacity of the high heating operating level at 5 
[deg]F. DOE has determined that such a scenario is possible and should 
be accounted for in the definition for the ``boost2 heating operating 
level'' and the requirements for the H5B2 test.
    As such, DOE is not adopting the definition for the ``boost2 
heating operating level'' in section 3.2.31.2 of AHRI 1340-2023. 
Instead, DOE is adopting the following definition for the ``boost2 
heating operating level'' in section 5.1 of appendix A1, which 
addresses the aforementioned scenario of a model with a boosted 
operating level at 17 [deg]F but not 5 [deg]F: ``An operating level 
allowed by the controls at 5.0 [deg]F outdoor dry-bulb temperature with 
a capacity at 5.0 [deg]F outdoor dry-bulb temperature that is less than 
or equal to the maximum capacity allowed by the controls at 5.0 [deg]F 
outdoor dry-bulb temperature, and greater than the capacity of: (a) the 
Boost Heating Operating Level at 5.0 [deg]F outdoor dry-bulb 
temperature, if there is an operating level that meets the definition 
for Boost Heating Operating Level specified in section 3.2.31.1 of AHRI 
1340-2023; or (b) the High Heating Operating Level at 5.0 [deg]F 
outdoor dry-bulb temperature, if there is not an operating level that 
meets the definition for Boost Heating Operating Level'' specified in 
section 3.2.31.1 of AHRI 1340-2023.
    Correspondingly, DOE is also specifying in section 5.2 of appendix 
A1 updated requirements for the H5B2 test of AHRI 1340-2023 that are to 
be used in case a model has no heating operating level that meets the 
definition of ``boost

[[Page 44013]]

heating operating level'' in section 3.2.31.1 of AHRI 1340-2023. 
Section 6.3.6 of AHRI 1340-2023 specifies to run the H5B2 test in Table 
23 to AHRI 1340-2023 with an operating level allowed by the controls at 
5.0 [deg]F outdoor dry-bulb temperature that has a capacity at 5.0 
[deg]F outdoor dry-bulb temperature that is greater than the capacity 
of the Boost Heating Operating Level at 5.0 [deg]F. In section 5.2 of 
appendix A1, DOE is instead adopting a revised version of that 
provision that replaces the comparison to capacity of the Boost Heating 
Operating Level at 5.0 [deg]F with a comparison to capacity of the High 
Heating Operating Level at 5.0 [deg]F.
    As noted previously, DOE has concluded that the inclusion of the 
boost2 heating operating level and the H5B2 test in AHRI 1340-2023 is 
generally consistent with the AHRI 1340-202X Draft. Similarly, DOE has 
concluded that the provisions discussed in this section (i.e., to allow 
use of the boost2 heating operating level for determining optional 
representations at 5 [deg]F for a model which has no boost heating 
operating level at 17 [deg]F, and to clarify which test should be used 
for optional COP25 representations depending on which 
heating operating levels apply at 5 [deg]F) maintain the proposed 
allowance for optional representations at 5 [deg]F, but add options and 
clarity for manufacturers to consistently determine this optional 
representation at the compressor speed most representative for a model.
    DOE understands that the AHRI Commercial Unitary STC also plans to 
address the aforementioned clarifications regarding the instructions 
for which test to use for optional representation of COP25 
and the definition of ``boost2 heating operating level'' that were 
published in AHRI 1340-2023. DOE expects that AHRI will consider 
including such clarifications in a future version of AHRI 1340, 
consistent with the clarifications adopted in this final rule.
d. Extrapolation of Boost Heating Operating Level to 21 [deg]F
    As discussed in section III.E.7.g of this final rule, AHRI 1340-
202X Draft requires interpolation of capacity and power between tests 
of the same operating level at different outdoor air temperatures when 
calculating values for the temperature bins used in IVHE and 
IVHEC. Extrapolation of capacity and power are not allowed 
in AHRI 1340-202X Draft.
    Sections 6.3.8 and 6.3.9 of AHRI 1340-2023 allow for capacity and 
power from boost heating operating level tests conducted at 5 [deg]F 
and 17 [deg]F to be used to extrapolate boost heating operating level 
performance up to 21 [deg]F. This allows manufacturers to take 
advantage of the boost heating operating level for calculations of the 
IVHE and IVHEC bins with outdoor air dry-bulb temperatures 
between 17 [deg]F and 22 [deg]F.\23\
---------------------------------------------------------------------------

    \23\ Table 22 of AHRI 1340-2023 specifies: (1) for the IVHE 
metric, bin temperatures of 21 [deg]F and 18.1 [deg]F for bin 
numbers 8 and 9; and (2) for the IVHEC metric, a bin 
temperature of 20.0 [deg]F for bin number 5.
---------------------------------------------------------------------------

    DOE has determined that these provisions are appropriate and will 
allow for more representative accounting of performance for bin 
temperatures between 17 [deg]F and 22 [deg]F, which are conditions at 
which models would likely operate at boost heating operating level, as 
necessary, to meet the building load, if the model operated as such for 
tests at 17 [deg]F (i.e., it would be unlikely that a model would have 
a boost operating level that engages at 17 [deg]F but not at 22 
[deg]F). Further, DOE has concluded that these provisions are generally 
consistent with the AHRI 1340-202X Draft in that the provisions 
maintain the same compressor operating levels for determining IVHE, but 
the upper temperature limit to which boost heating performance can be 
applied is being slightly extended (by 5 [deg]F, from 17 [deg]F to 22 
[deg]F) to more representatively account for performance between 17 
[deg]F to 22 [deg]F. Therefore, DOE is adopting the provisions allowing 
extrapolation of boost heating operating level performance in sections 
6.3.8 and 6.3.9 of AHRI 1340-2023.
e. Operating Levels Used for Optional COP217 Representations
    As previously mentioned in section III.E.8.c of this document, AHRI 
1340-2023 specifies that for units with a boost operating level, 
representations of COP25 is to be based on the capacity and 
power determined at the boost or boost 2 heating operating level 
denoted as the H5B or H5B2 test, instead of the H5H test. However, 
while AHRI 1340-2023 includes a boost operating level test at 17 [deg]F 
(the H17B test), section 6.3.14.2 of AHRI 1340-2023 requires that 
COP217 be determined using the capacity and power determined 
for the H17H test and does not allow for the COP217 to be 
determined using the capacity and power determined for the H17B test if 
conducted. Similar to its conclusions regarding the use of the H5B or 
H5B2 test for determining COP25, DOE has determined it would 
be appropriate to require the H17B test to be used for representations 
of COP217 if conducted because representations of efficiency 
at the maximum capacity for a given test condition are common and 
useful for consumers and utilities. Therefore, DOE is also specifying 
in this final rule that the H17B test, if conducted, be used for 
determining COP217, in order to allow manufacturers to make 
optional representations of capacity and performance at that operating 
level for models that are capable of boost operation. DOE understands 
that the AHRI Commercial Unitary STC also plans to specify that the 
H17B test is to be used for determining COP217 if this test 
is conducted. DOE expects that AHRI will consider including prescribing 
the use of the H17B test in appropriate cases for representations of 
COP217, consistent with this final rule, in a future version 
of AHRI 1340.
9. Test Procedure Revisions Recommended for a Future Rulemaking
    NYSERDA generally supported the proposed IVEC and IVHE metrics but 
commented that the heating test provisions proposed do not adequately 
account for fan energy consumed during auxiliary heating mode. 
(NYSERDA, No. 13 at pp. 2-3) NYSERDA recommended DOE consider the 
inclusion of an additional energy consumption term in the denominator 
of the IVHE calculation to account for supply fan energy use for 
commercial warm air furnaces, which NYSERDA stated would support 
recommendation #11 of the ACUAC and ACUHP Working Group TP Term Sheet. 
NYSERDA recommended addressing the fan energy consumption issue at the 
next appropriate juncture. (Id.)
    NEEA recommended DOE consider the following items the next time the 
CUAC/HP test procedure is reviewed: (1) impacts of outside air damper 
leakage; (2) energy saving potential from energy recovery ventilators 
(``ERV''); (3) benefits of variable-capacity or variable-speed 
compressors, and (4) a controls verification procedure (``CVP''). 
(NEEA, No. 16 at p. 4)
    At this time DOE has concluded that it does not have sufficient 
information or data to justify adopting deviations from the IVEC and 
IVHE metrics negotiated by the Working Group and included in the 
industry consensus test procedure AHRI 1340-2023. Therefore, DOE is 
adopting the IVEC and IVHE metrics as specified in AHRI 1340-2023.
    Regarding NYSERDA's comments on fan energy consumption in the IVHE 
metric, DOE notes that IVHE is the heating metric for CUHPs and assumes 
electric resistance supplementary heat for all models. Dual fuel CUHPs 
(i.e., CUHPs with gas furnace supplementary heat) will still have IVHE 
ratings that reflect electric resistance supplementary heat. The IVHE 
metric accounts for

[[Page 44014]]

supply fan energy during all hours with a heating load, regardless of 
whether the IVHE calculations assume the heating load is met by 
mechanical heating only, electric resistance heating only, or both, as 
described in section III.D.2 of this document. Therefore, DOE has 
concluded that no fan energy use for CUHPs is unaccounted for in the 
IVHE metric. DOE recognizes NEEA's suggested topics for consideration 
in a future test procedure rulemaking, but consistent with NEEA's 
comment, DOE is not addressing these topics in this final rule.

F. Configuration of Unit Under Test

1. Summary
    CUACs and CUHPs are sold with a wide variety of components, 
including many that can optionally be installed on or within the unit 
both at the factory and in the field. The following sections address 
the required configuration of units under test. In all cases, these 
components are distributed in commerce with the CUAC and CUHP but can 
be packaged or shipped in different ways from the point of manufacture 
for ease of transportation. Each optional component may or may not 
affect a model's measured efficiency when tested to the DOE test 
procedure adopted in this final rule. For certain components not 
directly addressed in the DOE test procedure, the August 2023 TP NOPR 
proposed more specific instructions on how each component should be 
handled for the purposes of making representations in 10 CFR part 429. 
88 FR 56392, 56430-56433 (August 17, 2023). Specifically, the proposed 
instructions were intended to provide manufacturers with clarity on how 
components should be treated and how to group individual models with 
and without optional components for the purposes of representations to 
reduce burden. Id. DOE proposed these provisions in 10 CFR part 429 to 
allow for testing of certain individual models that can be used as a 
proxy to represent the performance of equipment with multiple 
combinations of components. Id.
    In the August 2023 TP NOPR, DOE proposed to handle CUAC and CUHP 
components in two distinct ways to help manufacturers better understand 
their options for developing representations for their differing 
product offerings. Id. First, DOE proposed that the treatment of 
certain components be specified by the test procedure, such that their 
impact on measured efficiency is limited. Id. For example, a fresh air 
damper must be set in the closed position and sealed during testing, 
resulting in a measured efficiency that would be similar or identical 
to the measured efficiency for a unit without a fresh air damper. 
Second, DOE proposed provisions expressly allowing certain models to be 
grouped together for the purposes of making representations and 
allowing the performance of a model without certain optional components 
to be used as a proxy for models with any combinations of the specified 
components, even if such components would impact the measured 
efficiency of a model. Id. A steam/hydronic coil is an example of such 
a component. The efficiency representation for a model with a steam/
hydronic coil is based on the measured performance of the CUAC and CUHP 
as tested without the component installed because the steam/hydronic 
coil is not easily removed from the CUAC and CUHP for testing.\24\ Id.
---------------------------------------------------------------------------

    \24\ Note that in certain cases, as explained further in section 
III.F.3.b of this document, the representation may have to be based 
on an individual model with a steam/hydronic coil.
---------------------------------------------------------------------------

    In this final rule, DOE is adopting provisions regarding 
configuration of unit under test largely similar to those proposed, but 
with several differences from the proposed provisions, as discussed in 
the following sections. Specifically, the following sections provide a 
background for the proposed provisions, describe the proposed 
provisions, describe relevant updates in AHRI 1340-2023 that were not 
included in the AHRI 1340-202X Draft, summarize and respond to the 
comments that DOE received in response to the August 2023 TP NOPR, and 
discuss the provisions that DOE is adopting in this final rule.
2. Background
    In 2013, ASRAC formed the Commercial HVAC Working Group to engage 
in a negotiated rulemaking effort regarding the certification of 
certain commercial heating, ventilating, and air conditioning 
equipment, including CUACs and CUHPs. (See 78 FR 15653 (March 12, 
2013)) This Commercial HVAC Working Group submitted a term sheet 
(Commercial HVAC Term Sheet) providing the Commercial HVAC Working 
Group's recommendations. (See EERE-2013-BT-NOC-0023-0052 \25\) The 
Commercial HVAC Working Group recommended that DOE issue guidance under 
current regulations on how to test certain equipment features when 
included in a basic model, until such time as the testing of such 
features can be addressed through a test procedure rulemaking. The 
Commercial HVAC Term Sheet listed the subject features under the 
heading ``Equipment Features Requiring Test Procedure Action.'' (Id at 
pp. 3-9) The Commercial HVAC Working Group also recommended that DOE 
issue an enforcement policy stating that DOE would exclude certain 
equipment with specified features from DOE testing, but only when the 
manufacturer offers for sale at all times a model that is identical in 
all other features; otherwise, the model with that feature would be 
eligible for DOE testing. These features were listed under the heading 
``Equipment Features Subject to Enforcement Policy.'' (Id. at pp. 9-15)
---------------------------------------------------------------------------

    \25\ Available at www.regulations.gov/document/EERE-2013-BT-NOC-0023-0052.
---------------------------------------------------------------------------

    On January 30, 2015, DOE issued a Commercial HVAC Enforcement 
Policy addressing the treatment of specific features during DOE testing 
of commercial HVAC equipment. (See www.energy.gov/gc/downloads/commercial-equipment-testing-enforcement-policies) The Commercial HVAC 
Enforcement Policy stated that--for the purposes of assessment testing 
pursuant to 10 CFR 429.104, verification testing pursuant to 10 CFR 
429.70(c)(5), and enforcement testing pursuant to 10 CFR 429.110--DOE 
would not test a unit with one of the optional features listed for a 
specified equipment type if a manufacturer distributes in commerce an 
otherwise identical unit that does not include that optional feature. 
(Commercial HVAC Enforcement Policy at p. 1) The objective of the 
Commercial HVAC Enforcement Policy is to ensure that each basic model 
has a commercially-available version eligible for DOE testing. That is, 
each basic model includes a model either without the optional 
feature(s) listed in the policy or that is eligible for testing with 
the feature(s). Id. The features in the Commercial HVAC Enforcement 
Policy for CUACs and CUHPs (Id. at pp. 1-3 and 5-6) align with the 
Commercial HVAC Term Sheet's list designated ``Equipment Features 
Subject to Enforcement Policy.'' (EERE-2013-BT-NOC-0023-0052, pp. 9-15)
    By way of comparison, AHRI 340/360-2022 and AHRI 1340-202X Draft 
include appendix D, ``Unit Configuration for Standard Efficiency 
Determination--Normative.'' Section D3 to appendix D of AHRI 340/360-
2022 and AHRI 1340-202X Draft includes a list of features that are 
optional for testing, and it further specifies the following general 
provisions regarding testing of units with optional features:
     If an otherwise identical model (within the basic model) 
without the feature is not distributed in commerce, conduct tests with 
the feature according to the individual provisions specified in

[[Page 44015]]

section D3 to appendix D of AHRI 340/360-2022 and AHRI 1340-202X Draft.
     For each optional feature, section D3 to appendix D of 
AHRI 340/360-2022 and AHRI 1340-202X Draft includes explicit 
instructions on how to conduct testing for equipment with the optional 
feature present.
    The optional features provisions in AHRI 340/360-2022 and AHRI 
1340-202X Draft are generally consistent with DOE's Commercial HVAC 
Enforcement Policy, but the optional features in section D3 to appendix 
D of AHRI 340/360-2022 and AHRI 1340-202X Draft do not entirely align 
with the list of features included for CUACs and CUHPs in the 
Commercial HVAC Enforcement Policy.
    DOE notes that the list of features and provisions in section D3 to 
appendix D of AHRI 340/360-2022 and AHRI 1340-202X Draft conflate 
components that can be addressed by testing provisions with components 
that, if present on a unit under test, could have a substantive impact 
on test results and that cannot be disabled or otherwise mitigated. 
This differentiation was central to the Commercial HVAC Term Sheet, 
which as noted previously, included separate lists for ``Equipment 
Features Requiring Test Procedure Action'' and ``Equipment Features 
Subject to Enforcement Policy,'' and remains central to providing 
clarity in DOE's regulations. Therefore, in the August 2023 TP NOPR, 
DOE tentatively determined that provisions more explicit than those 
included in section D3 of appendix D of AHRI 340/360-2022 and AHRI 
1340-202X Draft are warranted to clarify treatment of models that 
include more than one optional component. 88 FR 56392, 56430 (August 
17, 2023).
    In order to provide clarity between test procedure provisions 
(i.e., how to test a specific unit) and certification and enforcement 
provisions (e.g., which model to test), DOE proposed in the August 2023 
TP NOPR to exclude appendix D of AHRI 340/360-2022 or AHRI 1340-202X 
Draft from adoption and instead proposed related provisions in 10 CFR 
429.43 and 429.134 and 10 CFR part 431, subpart F, appendices A and A1. 
Id.
3. Proposed Approach for Exclusion of Certain Components
    DOE's proposals in August 2023 TP NOPR for addressing treatment of 
certain components are discussed in the following sub-sections.
a. Components Addressed Through Test Provisions of 10 CFR Part 431, 
Subpart F, Appendices A and A1
    In the August 2023 TP NOPR, DOE proposed in 10 CFR part 431, 
subpart F, appendices A and A1, test provisions for specific 
components, including all of the components listed in section D3 to 
appendix D of AHRI 340/360-2022 and AHRI 1340-202X Draft, for which 
there is a test procedure action that limits the impacts on measured 
efficiency (i.e., test procedure provisions specific to the component 
that are not addressed by general provisions in AHRI 340/360-2022 or 
AHRI 1340-202X Draft that negate the component's impact on 
performance). 88 FR 56392, 56430 (August 17, 2023). These provisions 
would specify how to test a unit with such a component (e.g., for a 
unit with hail guards, remove hail guards for testing). These proposed 
test provisions were consistent with the provision in section D3 to 
appendix D of AHRI 340/360-2022 and AHRI 1340-202X Draft but include 
revisions for further clarity and specificity (e.g., adding clarifying 
provisions for how to test units with modular economizers as opposed to 
units shipped with economizers installed). Id. Specifically, DOE 
proposed to require in appendices A and A1 that steps be taken during 
unit set-up and testing to limit the impacts on the measurement of 
these components:

 Air Economizers
 Barometric Relief Dampers
 Desiccant Dehumidification Components
 Evaporative Pre-cooling of Air-cooled Condenser Intake Air
 Fire/Smoke/Isolation Dampers
 Fresh Air Dampers
 Hail Guards
 High-Effectiveness Indoor Air Filtration
 Power Correction Capacitors
 Process Heat Recovery/Reclaim Coils/Thermal Storage
 Refrigerant Reheat Coils
 Steam/Hydronic Heat Coils
 UV Lights
 Ventilation Energy Recovery Systems (VERS)

    The components were listed and described in the proposed table 1 to 
appendix A and table 1 to appendix A1. Test provisions for the 
components were provided in the tables. Id.
b. Components Addressed Through Representation Provisions of 10 CFR 
429.43
Overall Approach
    Consistent with the Commercial HVAC Term Sheet and the Commercial 
HVAC Enforcement Policy, in the August 2023 TP NOPR, DOE proposed 
provisions that explicitly allow representations for individual models 
with certain components to be based on testing for individual models 
without those components. 88 FR 56392, 56430-56433 (August 17, 2023). 
DOE proposed a table (table 6) at 10 CFR 429.43(a)(3)(v)(A) listing the 
components for which these provisions would apply. Id. 88 FR 56430-
56431. DOE proposed the following components be listed in table 6 to 10 
CFR 429.43(a)(3)(v)(A):

 Air Economizers
 Desiccant Dehumidification Components
 Evaporative Pre-cooling of Air-cooled Condenser Intake Air
 Fire/Smoke/Isolation Dampers
 Indirect/Direct Evaporative Cooling of Ventilation Air
 Non-Standard Ducted Condenser Fans
 Non-Standard Indoor Fan Motors
 Powered Exhaust/Powered Return Air Fans
 Process Heat Recovery/Reclaim Coils/Thermal Storage
 Refrigerant Reheat Coils
 Sound Traps/Sound Attenuators
 Steam/Hydronic Heat Coils
 Ventilation Energy Recovery Systems (VERS)

    In the August 2023 TP NOPR, DOE proposed to specify that the basic 
model representation must be based on the least-efficient individual 
model that comprises a basic model, and clarified how this long-
standing basic model provision interacts with the proposed component 
treatment in 10 CFR 429.43. Id. 88 FR 56431-56432. DOE tentatively 
concluded that regulated entities may benefit from clarity in the 
regulatory text as to how the least-efficient individual model within a 
basic model provision works in concert with the component treatment for 
CUACs and CUHPs. Id. The amendments proposed in the August 2023 TP NOPR 
explicitly state that excluding the specified components from 
consideration in determining basic model efficiency in certain 
scenarios is an exception to basing representations on the least-
efficient individual model within a basic model. Id. In other words, 
the components listed in 10 CFR 429.43 are not being considered as part 
of the representation under DOE's regulatory framework if certain 
conditions are met as discussed in the following paragraphs, and, thus, 
their impact on efficiency is not reflected in the representation. In 
this case, the basic model's representation is generally determined by 
applying the testing and

[[Page 44016]]

sampling provisions to the least-efficient individual model in the 
basic model that does not have a component listed in 10 CFR 429.43.
    DOE proposed clarifying instructions for instances when individual 
models within a basic model may have more than one of the specified 
components and there may be no individual model without any of the 
specified components. Id. DOE proposed the concept of an otherwise 
comparable model group (``OCMG''). Id. An OCMG is a group of individual 
models within the basic model that do not differ in components that 
affect energy consumption as measured according to the applicable test 
procedure other than the specific components listed in table 6 to 10 
CFR 429.43(a)(3)(v)(A) but may include individual models with any 
combination of such specified components. Therefore, a basic model can 
be composed of multiple OCMGs, each representing a unique combination 
of components that affect energy consumption as measured according to 
the applicable test procedure, other than the specified excluded 
components listed in table 6 to 10 CFR 429.43(a)(3)(v)(A). For example, 
a manufacturer might include two tiers of control systems within the 
same basic model, in which one of the control systems has sophisticated 
diagnostics capabilities that require a more powerful control board 
with a higher wattage input. CUAC and CUHP individual models with the 
``standard'' control system would be part of OCMG A, while individual 
models with the ``premium'' control system would be part of a different 
OCMG B, because the control system is not one of the specified exempt 
components listed in table 6 to 10 CFR 429.43(a)(3)(v)(A). However, 
both OCMGs may include different combinations of specified exempt 
components. Also, both OCMGs may include any combination of 
characteristics that do not affect the efficiency measurement, such as 
paint color.
    An OCMG identifies which individual models are to be used to 
determine a represented value. Id. Specifically, when identifying the 
individual model within an OCMG for the purpose of determining a 
representation for the basic model, only the individual model(s) with 
the least number (which could be zero) of the specific components 
listed in table 6 to 10 CFR 429.43(a)(3)(v)(A) is considered. This 
clarifies which individual models are exempted from consideration for 
determination of represented values in the case of an OCMG with 
multiple specified components and no individual models with zero 
specific components listed in table 6 to 10 CFR 429.43(a)(3)(v)(A) 
(i.e., models with a number of specific components listed in table 6 
greater than the least number in the OCMG are exempted). In the case 
that the OCMG includes an individual model with no specific components 
listed in table 1 to 10 CFR 429.43(a)(3)(i)(A), then all individual 
models in the OCMG with specified components would be exempted from 
consideration. The least-efficient individual model across the OCMGs 
within a basic model would be used to determine the representation of 
the basic model. In the case where there are multiple individual models 
within a single OCMG with the same non-zero least number of specified 
components, the least efficient of these would be considered.
    DOE relies on the term ``comparable'' as opposed to ``identical'' 
to indicate that, for the purpose of representations, the components 
that impact energy consumption as measured by the applicable test 
procedure are the relevant components to consider. Id. In other words, 
differences that do not impact energy consumption, such as unit color 
and presence of utility outlets, would not warrant separate OCMGs.
    The use of the OCMG concept results in the represented values of 
performance that are representative of the individual model(s) with the 
lowest efficiency found within the basic model, excluding certain 
individual models with the specific components listed in table 6 to 10 
CFR 429.43(a)(3)(v)(A). Id. Specifically with regard to basic models of 
CUACs and CUHPs distributed in commerce with multiple different heating 
capacities of furnaces, the individual model with the lowest efficiency 
found within the basic model (with the aforementioned exception) would 
likely include the furnace with the highest offered heating capacity. 
Additionally, selection of the individual model with the lowest 
efficiency within the basic model would be required to consider all 
options for factory-installed components and manufacturer-supplied 
field-installed components (e.g., electric resistance supplementary 
heat), excluding the specific components listed in table 6 to 10 CFR 
429.43(a)(3)(v)(A). If manufacturers want to represent more-efficient 
models within the same group, they would be able to establish those 
units as new basic models and test and report the results accordingly. 
Further, the approach, as proposed, is structured to more explicitly 
address individual models with more than one of the specific components 
listed in table 6 to 10 CFR 429.43(a)(3)(v)(A), as well as instances in 
which there is no comparable model without any of the specified 
components. DOE developed a document of examples to illustrate the 
approach proposed in the August 2023 TP NOPR for determining 
represented values for CUACs and CUHPs with specific components, and in 
particular the OCMG concept (see EERE-2023-BT-TP-0014-0001).
    DOE's proposed provisions in 10 CFR 429.43(a)(3)(v)(A) include each 
of the components specified in section D3 of AHRI 340/360-2022 for 
which the test provisions for a unit with these components may result 
in differences in ratings compared to testing a unit without these 
components. 88 FR 56392, 56431-56432 (August 17, 2023). DOE's proposed 
treatment for non-standard indoor fan motors and coated coils is 
discussed in the following sub-sections.
High-Static Non-Standard Indoor Fan Motors
    The Commercial HVAC Enforcement Policy includes high-static indoor 
blowers or oversized motors as an optional feature for CUACs and CUHPs, 
among other equipment. The Commercial HVAC Enforcement Policy states 
that when selecting a unit of a basic model for DOE[hyphen]initiated 
testing, if the basic model includes a variety of high-static indoor 
blowers or oversized motor options,\26\ DOE will test a unit that has a 
standard indoor fan assembly (as described in the supplemental test 
instructions (``STI'') that is part of the manufacturer's 
certification, including information about the standard motor and 
associated drive that was used in determining the certified rating). 
This policy only applies where: (a) the manufacturer distributes in 
commerce a model within the basic model with the standard indoor fan 
assembly (i.e., standard motor and drive), and (b) all models in the 
basic model have a motor with the same or better relative efficiency 
performance as the standard motor included in the test unit, as 
described in a separate guidance document discussed subsequently. If 
the manufacturer does not offer models with the standard motor 
identified in the STI or offers models with high-static motors that do 
not comply with the

[[Page 44017]]

comparable efficiency guidance, DOE will test any indoor fan assembly 
offered for sale by the manufacturer.
---------------------------------------------------------------------------

    \26\ The Commercial HVAC Enforcement Policy defines ``high 
static indoors blower or oversized motor'' as an indoor fan 
assembly, including a motor, that drives the fan and can deliver 
higher external static pressure than the standard indoor fan 
assembly sold with the equipment. (See www.energy.gov/sites/default/files/2019/04/f62/Enforcement_Policy-Commercial_HVAC.pdf. at p.6)
---------------------------------------------------------------------------

    DOE subsequently issued a draft guidance document (Draft Commercial 
HVAC Guidance Document) on June 29, 2015 to request comment on a method 
for comparing the efficiencies of a standard motor and a high-static 
indoor blower/oversized motor.\27\ As presented in the Draft Commercial 
HVAC Guidance Document, the relative efficiency of an indoor fan motor 
would be determined by comparing the percentage losses of the standard 
indoor fan motor to the percentage losses of the non-standard 
(oversized) indoor fan motor. The percentage losses would be determined 
by comparing each motor's wattage losses to the wattage losses of a 
corresponding reference motor. Additionally, the draft method contains 
a table that includes a number of situations with different 
combinations of characteristics of the standard motor and oversized 
motor (e.g., whether each motor is subject to Federal standards for 
motors; whether each motor can be tested to the Federal test procedure 
for motors; whether each motor horsepower is less than 1 and specifies 
for each combination whether the non-standard fan enforcement policy 
would apply (i.e., whether DOE would not test a model with an oversized 
motor, as long as the relative efficiency of the oversized motor is at 
least as good as performance of the standard motor)). DOE has not 
issued a final guidance document and is instead addressing the issue 
for CUACs and CUHPs in this test procedure rulemaking.
---------------------------------------------------------------------------

    \27\ Available at www1.eere.energy.gov/buildings/appliance_standards/pdfs/draft-commercial-hvac-motor-faq-2015-06-29.pdf.
---------------------------------------------------------------------------

    The current Federal test procedure does not address this issue. 
Section D4.1 of appendix D of AHRI 340/360-2022 and AHRI 1340-202X 
Draft provide an approach for including an individual model with a non-
standard indoor fan motor as part of the same basic model as an 
individual model with a standard indoor fan motor. Under the approach 
in section D4.1 of appendix D of AHRI 340/360-2022 and AHRI 1340-202X 
Draft, the non-standard indoor fan motor efficiency must exceed the 
minimum value calculated using equation D1 in appendix D of AHRI 340/
360-2022 and AHRI 1340-202X Draft. This minimum non-standard motor 
efficiency calculation is dependent on the efficiency of the standard 
fan motor and the reference efficiencies (determined per Table D1 of 
appendix D of AHRI 340/360-2022 and AHRI 1340-202X Draft) of the 
standard and non-standard fan motors.
    Section D4.2 of appendix D of AHRI 340/360-2022 and AHRI 1340-202X 
Draft contain a method for how to compare performance for integrated 
fans and motors (IFMs). Because the fan motor in an IFM is not 
separately rated from the fan, this method compares the performance of 
the entire fan-motor assemblies for the standard and non-standard IFMs, 
rather than just the fan motors. This approach enables comparing 
relative performance of standard and non-standard IFMs, for which motor 
efficiencies could otherwise not be compared using the method specified 
in section D4.1 of appendix D of AHRI 340/360-2022 or AHRI 1340-202X 
Draft. Specifically, this method determines the ratio of the input 
power of the non-standard IFM to the input power of the standard IFM at 
the same duty point as defined in section D4.2 of appendix D of AHRI 
340/360-2022 and AHRI 1340-202X Draft (i.e., operating at the maximum 
ESP for the standard IFM at the rated airflow). If the input power 
ratio does not exceed the maximum ratio specified in Table D3 of 
appendix D of AHRI 340/360-2022 and AHRI 1340-202X Draft, the 
individual model with the non-standard IFM may be included within the 
same basic model as the individual model with the standard IFM. Section 
D4.2 of appendix D of AHRI 340/360-2022 and AHRI 1340-202X Draft allow 
these calculations to be conducted using either test data or simulated 
performance data.
    The approaches in section D4 of appendix D of AHRI 340/360-2022 and 
AHRI 1340-202X Draft for high-static non-standard indoor fan motors and 
non-standard indoor IFMs generally align with the approaches of the 
Commercial HVAC Term Sheet, the Commercial HVAC Enforcement Policy, and 
the Draft Commercial HVAC Guidance Document, while providing greater 
detail and accommodating a wider range of fan motor options. For the 
reasons presented in the preceding paragraphs, DOE proposed in the 
August 2023 TP NOPR to adopt in table 6 to 10 CFR 429.43(a)(3)(v)(A) 
the provisions for comparing performance of standard and high-static 
non-standard indoor fan motors/IFMs in section D4 of appendix D of AHRI 
340/360-2022 and AHRI 1340-202X Draft \28\ for the determination of the 
represented efficiency value for CUACs and CUHPs at 10 CFR 
429.43(a)(3). 88 FR 56392, 56432 (August 17, 2023).
---------------------------------------------------------------------------

    \28\ Per DOE's existing certification regulations, if a 
manufacturer were to use the proposed approach to certify a basic 
model, the manufacturer would be required to maintain documentation 
of how the relative efficiencies of the standard and non-standard 
fan motors or the input powers of the standard and non-standard IFMs 
were determined, as well as the supporting calculations. See 10 CFR 
429.71.
---------------------------------------------------------------------------

Coated Coils
    In the August 2023 TP NOPR, DOE proposed to exclude coated coils 
from the specific components list specified in 10 CFR 429.43 because 
DOE tentatively concluded that the presence of coated coils does not 
result in a significant impact to performance of CUACs and CUHPs, and, 
therefore, models with coated coils should be rated based on 
performance of models with coated coils present (rather than based on 
performance of an individual model within an OCMG without coated 
coils). 88 FR 56392, 56432-56433 (August 17, 2023).
c. Enforcement Provisions of 10 CFR 429.134
    Consistent with the Commercial HVAC Term Sheet and the Commercial 
HVAC Enforcement Policy, in the August 2023 TP NOPR, DOE proposed 
provisions in 10 CFR 429.134(g)(2) regarding how DOE would assess 
compliance for basic models of CUACs and CUHPs that include individual 
models distributed in commerce if DOE cannot obtain for testing 
individual models without certain components consistent with the model 
that served as the basis of representation. 88 FR 56392, 56433 (August 
17, 2023). Specifically, DOE proposed that if a basic model includes 
individual models with components listed at table 6 to 10 CFR 
429.43(a)(3)(v)(A) and DOE is not able to obtain an individual model 
with the least number of those components within an OCMG (as defined in 
the proposed 10 CFR 429.43(a)(3)(v)(A)(1) and discussed in section 
III.F.3.b of this final rule), DOE may test any individual model within 
the OCMG. Id.
d. Testing Specially Built Units That Are Not Distributed in Commerce
    Unlike section D3 to appendix D of AHRI 340/360-2022 and AHRI 1340-
202X Draft, DOE's Commercial HVAC Enforcement Policy does not allow a 
manufacturer to test a model that is specially built for testing 
without a feature if models without that feature are not actually 
distributed in commerce. Because testing such specially built models 
would not provide ratings representative of equipment distributed in 
commerce, DOE tentatively concluded in the August 2023 TP NOPR that 
such

[[Page 44018]]

approach is not appropriate. 88 FR 56392, 56433 (August 17, 2023). 
Therefore, consistent with the Commercial HVAC Enforcement Policy, DOE 
did not propose to allow testing of specially built units in its 
representation and enforcement provisions. Id.
4. Updates in AHRI 1340-2023
    In the final version of AHRI 1340-2023, appendix D to AHRI 1340-
2023 was updated to align with the approach and list of features 
proposed by DOE in the August 2023 TP NOPR, as discussed in section 
III.F.3 of this final rule. In addition, Table 37 to appendix D to AHRI 
1340-2023 includes instructions specifying that drain pan heaters be 
disconnected during testing. DOE's consideration of this AHRI 1340-2023 
provision for drain pan heaters is discussed in the following section.
5. Comments Received and Adopted Provisions
a. Overall Approach
    DOE received several comments pertaining to DOE's proposed 
approach. Carrier stated that DOE's proposal for specific components 
was not fully clear to Carrier, but that if the intent is that the 
lowest-efficiency model should be used for representations of 
performance, Carrier agrees with that approach. (Carrier, No. 8 at p. 
3) For rating models, Carrier also agreed that specially built models 
not distributed in commerce should not be allowed for compliance 
testing used to determine ratings. (Id.) Carrier commented that 
breaking into separate groups of components and introducing an 
additional concept of OCMG could create further confusion and undue 
complexity. (Id.) Carrier stated that it would like to see these 
provisions for specific components be laid out in a more 
straightforward manner to provide manufacturers clarity when choosing 
models for representations. (Id.) Rheem similarly commented that the 
proposed OCMG concept lacks clarity and recommended DOE explore ways to 
make the proposed regulatory text clearer with visual aids or examples. 
(Rheem, No. 12 at p. 2) Rheem recommended the regulatory language to 
remain the same as it is currently if no further explanation is 
provided. (Id.)
    Regarding Carrier and Rheem's concerns, DOE's intent is for the 
lowest-efficiency model within a basic model to be used for 
representations of performance, as is stated in the provisions adopted 
at 10 CFR 429.43(a)(3)(vi)(A)(1) in this final rule.\29\ DOE 
acknowledges that the ability to exclude certain specific components 
specified in table 7 to 10 CFR 429.43(a)(3)(vi)(A) from consideration 
when identifying the lowest-efficiency model means that there could be 
confusion in determining the least-efficient model(s) that can be used 
to determine representations for the basic model. This is the reason 
that the OCMG concept is required. As discussed, the OCMG formalizes 
the process by which a manufacturer can consider groups of individual 
models within a basic model that are comparable, other than the 
presence of certain specific components specified in table 7 to 10 CFR 
429.43(a)(3)(vi)(A), and determine the individual model(s) that can be 
used to determine representations for the basic model. This ensures 
that the process is performed in the same way by all manufacturers and 
also by DOE, thereby preventing the potential for confusion and 
inaccurate representations. Regarding Carrier's and Rheem's requests 
for more clarity and visual aids, DOE notes that, as discussed, the 
Department has developed a document which includes visual aids and 
examples of how the OCMG concept works in application (see EERE-2023-
BT-TP-0014-0001). This document presents several examples that make 
clear the OCMG concept and how it is used to determine the individual 
model(s) that can be used to determine representations for a basic 
model. DOE encourages stakeholders to review this document for 
additional clarification, and the Department will consider developing 
other forms of visual aid and examples should stakeholders request it.
---------------------------------------------------------------------------

    \29\ In the August 2023 TP NOPR, DOE proposed the provisions 
regarding certain components addressed through representation 
provisions of 10 CFR 429.43(a)(3)(v). In this final rule, those 
provisions are instead being adopted at 10 CFR 429.43(a)(3)(vi). 
Further, the provisions proposed in table 6 to 10 CFR 
429.43(a)(3)(v)(A) are being adopted in table 7 to 10 CFR 
429.43(a)(3)(vi)(A).
---------------------------------------------------------------------------

    For the reasons discussed in the previous paragraphs and the August 
2023 TP NOPR, DOE is adopting its proposed approach for determining the 
configuration of a unit under test. DOE is also adopting two updates to 
the approach proposed in the August 2023 TP NOPR, as explained in the 
paragraphs that follow.
    First, after consideration of comments received, DOE is changing 
the required compliance date to be when certifying to standards 
denominated in terms of IVHE and IVEC, should those standards be 
established, rather than starting 360 days after publication of the 
test procedure final rule in the Federal Register (as proposed). This 
is consistent with the approach that DOE has taken for establishing 
similar provisions for other categories of commercial air conditioning 
equipment; i.e., for other categories such as CRACs (88 FR 21816, 
21836-21837 (April 11, 2023)), variable refrigerant flow multi-split 
systems (87 FR 63860, 63892 (Oct. 20, 2022)), and SPVUs (87 FR 75144, 
75166 (Dec. 7, 2022)), DOE specified a compliance date for similar 
``configuration of unit under test'' provisions to be the compliance 
date of amended energy conservation standards in terms of the new 
metric. Additionally, this compliance date change ensures that 
manufacturers will have adequate time to learn and understand the 
process. As a result, the provisions that DOE is adopting in 10 CFR 
429.43 and 429.134 will apply when certifying to standards denominated 
in terms of IVHE and IVEC or for assessment and enforcement testing of 
models subject to energy conservation standards denominated in terms of 
IVEC and IVHE, if such standards are adopted. Consistent with the 
compliance date for provisions in 10 CFR 429.43 and 429.134, DOE is 
also not adopting any test provisions for units with specific 
components in appendix A, and is instead only adopting such test 
provisions in appendix A1, which would be used when certifying 
compliance with standards in terms of IVHE and IVEC, should those 
standards be established.
    Second, DOE is adopting in table 2 to appendix A1 the provision for 
how to test units with drain pan heaters specified in Table 37 to 
appendix D2 to AHRI 1340-2023 (i.e., disconnect drain pan heaters for 
testing). Although not proposed in the August 2023 TP NOPR, DOE has 
concluded that this guidance for how to test units with drain pan 
heaters is appropriate and consistent with test provisions for other 
components that DOE proposed in the August 2023 TP NOPR.
    As discussed, DOE's adopted provisions regarding configuration of 
unit under test in 10 CFR 429.43 and 429.134 apply to equipment subject 
to standards in terms of IVHE and IVEC.
b. Coated Coils
    DOE received several comments in response to the proposal to 
exclude coated coils from the specific components list in 10 CFR 
429.43. Carrier, Trane, AHRI, and Lennox opposed DOE's proposed 
exclusion of coated coils from the specific components list. (Carrier, 
No. 8 at p. 3; Trane, No. 14 at p. 4; AHRI, No. 15 at p. 6; Lennox, No. 
9 at p. 2) AHRI asserted that DOE provided no data to support the 
proposal and that the

[[Page 44019]]

proposal could more than double manufacturers' listed basic models. 
(AHRI, No. 15 at p. 6)
    Trane stated that there are a multitude of coil coatings available 
in the marketplace and that many are customized per specific customer 
requests. (Trane, No. 14 at p. 4) Trane further commented that many 
coils undergo a special ``non-standard'' process to have coil coatings 
applied, often requiring coils to be sent to a third party prior to 
being installed in the unit during the manufacturing process, which 
adds significant lead time to the equipment as well as variability in 
types of coatings that are applied. (Id.) Trane argued that excluding 
coated coils from the list of specific components would necessitate 
extensive testing in order to develop adequate performance models for 
all cases. (Id.) Trane additionally stated that this would also 
multiply the number of listed models, as some coil coatings may have 
significant performance impacts while some may not. (Id.) Trane stated 
that units with coated coils only represent a very small fraction of 
the market, and, therefore, requiring all equipment to include coil 
coatings in the basic models is not representative of the vast majority 
of applications in the marketplace. (Id.) Trane also argued that this 
requirement would be unduly burdensome for manufacturers, given that 
coated coils represent such a small share of the market. (Id.)
    Carrier stated that there is a negative impact to performance when 
a unit is first produced with coated coils, but Carrier asserted that 
the coating prevents degradation over the lifetime of the unit as 
compared to a unit with an uncoated coil in certain applications. 
(Carrier, No. 8 at p. 3) In the event that coated coils are removed 
from the list of specific components, Carrier stated that it is 
concerned that energy conservation will be reduced over the life of 
products in the applications that require these components. (Id.) If 
coated coils are excluded from the list of specific components, Carrier 
opposed the proposed 360-day compliance date for requirements for 
representations of those models, stating that compliance would require 
additional laboratory time and engineering resources that are currently 
fully allocated to refrigerating transition projects required to meet 
the Environmental Protection Agency's January 1, 2025 compliance date. 
(Id.)
    In response, DOE notes that the comments received in response to 
the August 2023 TP NOPR indicate that some coil coatings may not have a 
significant impact on performance while other coil coatings would. 
Given that comments suggest that certain implementations of coated 
coils do not impact energy use whereas others do, DOE has determined 
that for those units for which coated coils do impact energy use, 
representations should include those impacts, thereby providing full 
disclosure for commercial customers.
    Regarding Trane's assertion that including coated coils in 
representations would be unduly burdensome and assertions that the 
proposal would significantly increase the number of listed basic 
models, DOE notes that not all coil coatings would necessarily warrant 
separate basic models. DOE's definition for ``basic model'' at 10 CFR 
431.92 specifies that a basic model for CUACs and CUHPs can comprise 
models with ``comparably performing'' heat exchangers, which allows for 
models with small variations in performance still to be included 
together in the same basic model, so long as, consistent with the 
clarifications adopted and previously discussed in this final rule, the 
representations for the basic model are based on the least-efficient 
configuration. Therefore, coil coatings with similar performance 
impacts could be rated within the same basic model, and coil coatings 
without a significant impact on performance could be included in the 
same basic model as models with no coil coatings.
    DOE expects that manufacturers already have a general understanding 
of which coil coatings might have significant impacts on performance, 
based on coil coating material and thickness. To the extent that a 
manufacturer needs to determine whether a coil coating impacts 
performance, the manufacturer could presumably determine this for a 
given model and apply that understanding to other models. In other 
words, a given coil coating is likely to have similar impacts across 
all basic models of CUACs and CUHPs, such that finding that the coating 
has no substantive impact on performance for a given model likely 
indicates such a finding would apply to other models as well. Thus, DOE 
expects that there would be no need to separately confirm ``no impact'' 
from a given coil coating on each basic model for which it is offered. 
Further, DOE notes that AEDMs can be used to simulate performance of 
models with coated coils such that not all models require testing. 
Therefore, DOE has concluded that the proposed approach for coated 
coils is not unduly burdensome.
    DOE disagrees with Trane's comment that requiring all equipment to 
include coil coatings in the basic models is not representative of the 
vast majority of applications in the marketplace. The proposed approach 
does not require that all representations for CUACs and CUHPs be based 
on the presence of coil coatings; to the extent that manufacturers 
offer a model with and without a coil coating that substantively 
impacts performance, the manufacturer can rate as separate basic models 
with and without the coil coatings. The basic model with ratings based 
on performance without the coil coating would represent the shipments 
of units without coil coatings. Further, for coil coatings that impact 
performance, ratings based on the presence of coil coatings are 
representative of shipments of units with such coil coatings, and 
performance ratings based on the presence of the coil coating provide a 
more accurate assessment of the unit's energy consumption to commercial 
consumers.
    Regarding AHRI's assertion that DOE has not provided any data to 
support its proposal, DOE notes that comments received from both Trane 
and Carrier indicate that some coil coatings have negative performance 
impacts. Therefore, DOE concludes that no further data are needed to 
justify adopting a provision requiring that ratings reflect coated 
coils with substantive negative performance impacts, as this is 
consistent with DOE's statutory authority to prescribe test procedures 
that produce results that are representative of an average use cycle. 
Additionally, as discussed earlier in this section, to the extent that 
manufacturers produce units with coated coils that do not impact 
performance as compared to units with uncoated coils, the manufacturer 
may group such individual models together within the same basic model.
    DOE disagrees with Carrier's assertion that including coated coils 
in representations will result in energy conservation being reduced 
over the life of products in the applications that require coated 
coils. DOE expects that commercial customers who are currently 
purchasing CUACs and CUHPs with coated coils do so because they 
understand coil protection to be important for their application, and 
DOE does not expect that such consumers would stop purchasing units 
with coated coils if ratings are required to reflect performance 
impacts of coated coils. However, the incorporation of performance 
impacts of coated coils into ratings for CUACs and CUHPs will provide 
commercial consumers with more accurate assessments of the energy 
consumption of various models of CUACs and CUHPs, and will, therefore,

[[Page 44020]]

better elucidate any performance trade-offs associated with coil 
coatings and will better inform consumers as to coil coatings that may 
have less performance impact than others.
    Regarding Carrier's concern about the timeline for required 
representations with coated coils, as previously discussed, DOE is 
adopting all provisions for specific components with a compliance date 
starting when certifying to standards in terms of IVHE and IVEC, should 
those standards be established, instead of the proposed compliance date 
of 360 days after publication of the final rule in the Federal 
Register. DOE has concluded that the adopted compliance date will 
provide adequate lead time for manufacturers to develop representations 
that reflect the amended test procedure and representation provisions 
adopted in this final rule.
    For the reasons described in the previous paragraphs and consistent 
with the proposals in the August 2023 TP NOPR, DOE is not incorporating 
coated coils into DOE's provisions specified in 10 CFR 429.43(a)(3) 
that allow for the exclusion of specified components when determining 
represented values for CUACs and CUHPs.

G. Represented Values

    In the following sections, DOE discusses requirements regarding 
represented values. To the extent DOE is adopting changes to the 
requirements specified in 10 CFR 429 regarding representations of CUACs 
and CUHPs, such amendments to 10 CFR part 429, will be required: (1) 
starting 360 days after the date of publication in the Federal Register 
of this final rule when certifying to an EER, IEER, or COP standard or 
(2) starting on the compliance date of amended energy conservation 
standards denominated in terms of IVEC or IVHE, should DOE adopt such 
standards. Prior to 360 days after the date of publication in the 
Federal Register of this final rule, the current requirements will 
apply.
1. Cooling Capacity
    In the August 2023 TP NOPR, DOE proposed to adopt provisions 
relating to the represented value of cooling capacity at 10 CFR 
429.43(a)(1)(iv), as well as the verification of cooling capacity 
during enforcement testing at 10 CFR 429.134(g). 88 FR 56392, 56433-
56434 (August 17, 2023). The following sections include discussion of 
the proposals in the NOPR, responses to related comments, and the 
approaches adopted in this final rule.
a. Representations of Cooling Capacity
    For CUACs and CUHPs, cooling capacity determines equipment class, 
which in turn determines the applicable energy conservation standard. 
10 CFR 431.97. Cooling capacity also dictates the minimum ESP test 
condition applicable under Table 7 of AHRI 340/360-2022 (i.e., larger 
capacity units are required to be tested at higher ESPs), which in turn 
affects the performance of the unit. Cooling capacity is a required 
represented value for all CUACs and CUHPs, but the requirements 
currently specified in 10 CFR 429.43(a)(1)(iv) regarding how the 
represented value of cooling capacity is determined only apply to 
ACUACs and ACUHPs.
    In the August 2023 TP NOPR, DOE proposed to make certain 
modifications to these provisions and to expand the applicability of 
these provisions, as amended, to all of the CUACs and CUHPs that are 
the subject of this rulemaking. Specifically, DOE proposed that the 
represented value of cooling capacity must be between 95 and 100 
percent of the mean of the total cooling capacities measured for the 
units in the sample. 88 FR 56392, 56433 (August 17, 2023). DOE also 
proposed in the August 2023 TP NOPR that for units where the 
represented value is determined through an AEDM, the represented value 
of cooling capacity must be between 95 and 100 percent of the total 
cooling capacity output simulated by the AEDM. Id. Additionally, DOE 
proposed to remove the existing requirement in 10 CFR 429.43(a)(1)(iv) 
that the represented value of cooling capacity correspond to the 
nearest appropriate Btu/h multiple according to Table 4 of ANSI/AHRI 
340/360-2007 in order to allow manufacturers flexibility in certifying 
a rated value that provides a representation of cooling capacity that 
may be more meaningful for commercial consumers. Id. DOE argued that 
these proposals would ensure that the rated capacity is representative 
of the unit's performance, while allowing manufacturers to 
conservatively rate capacity if the manufacturer deemed such 
conservative rating necessary to ensure that equipment is capable of 
performing at the cooling capacity for which it is represented to 
consumers. Id. DOE requested comment on its proposals related to the 
representation of cooling capacity. Id.
    Carrier supported DOE's cooling capacity representation proposal. 
(Carrier, No. 8 at p. 4) AHRI commented that it opposes DOE's proposal 
that represented capacity must be between 95 to 100 percent of measured 
or simulated capacity for units where the represented value is 
determined through an AEDM, asserting that this tolerance is too narrow 
given that manufacturers can rate capacity at 95 percent of development 
tests. AHRI further argued that the proposal allows for no (0 percent) 
tolerance for variation because tested capacity during enforcement 
could be at 105 percent (per DOE's proposal regarding cooling capacity 
used to determine ESP requirements during DOE testing, which is 
discussed in section III.G.1.b of this final rule). (AHRI, No. 15 at p. 
6) Rheem commented that it opposed DOE's proposal for a one-sided 
tolerance to be within 95 to 100 percent of rated cooling capacity, 
arguing that this tolerance does not provide enough margin to account 
for factors that affect measurements such as manufacturing variation 
and test lab conditions. Instead, Rheem recommended that DOE consider 
adoption of a wider two-sided tolerance that accounts for measurement 
variability, such as 90 to 110 percent of rated capacity. (Rheem, No. 
12 at p. 2) Lennox similarly commented that it opposes DOE's proposal 
to require that the measured cooling capacity must be between 95 and 
100 percent of the represented value and argued the proposed tolerance 
is too narrow, given that manufacturers can rate up to 100 percent of 
the tested value. Lennox recommended DOE instead provide a tolerance 
range for measured capacity between 95 and 105 percent. (Lennox, No. 9 
at p. 2)
    As previously expressed, DOE's proposal to limit the represented 
value of cooling capacity to be within 95 and 100 percent of the mean 
of the total cooling capacities measured for the units in the sample 
(or simulated by an AEDM) was intended to allow manufacturers to 
conservatively rate capacity if the manufacturer deemed such 
conservative rating necessary to ensure that equipment is capable of 
performing at the cooling capacity for which it is represented to 
consumers, but it was also intended to prevent manufacturers from over-
rating capacity. Comments from Rheem and Lennox suggest that the 
commenters misunderstood the proposal to be imposing a tolerance on the 
measured cooling capacity that is compared to the rated cooling 
capacity. To clarify, this provision specifies how represented values 
of cooling capacity are determined based on the sample of measured 
values (or values calculated in an AEDM) for a given basic model. 
Verification of rated cooling capacity, which is a separate issue, is 
discussed in the following section.

[[Page 44021]]

    Rated cooling capacity is used to determine the ESP requirements 
used in testing; therefore, DOE has concluded that significant 
underrating or overrating of capacity could cause unintended 
consequences such as inequitable ratings due to differences in self 
declarations. Further, significant underrating or overrating of 
capacity would provide an inaccurate assessment to consumers of the 
amount of space cooling a model can provide. Additionally, the 95 to 
100 percent tolerance is consistent with what has been adopted for 
other categories of commercial air-conditioning, such as DX-DOASes, 
SPVUs, and CRACs. See 10 CFR 429.43(a)(3)(i)(B)(1), (a)(3)(iii)(B), and 
(a)(3)(iv)(B).
    Regarding comments on manufacturing variation and test variability, 
DOE notes that if a manufacturer develops ratings for a basic model 
based on testing, the manufacturer must test in accordance with 10 CFR 
429.43(a)(1), which requires testing to be conducted on a sample 
consistent of no less than two units per basic model. The provisions at 
10 CFR 429.43(a)(1) specify statistics used to develop represented 
values based on the mean and standard deviation of measurements--i.e., 
reflecting the variation in measurements included in the sample. If a 
manufacturer chooses to consider more units or variation in measured 
performance using different test chambers, DOE does not limit the 
number of units or test chambers that can be used in the sample to 
develop a rating for a basic model. In other words, a manufacturer can 
include in the sample results from all testing it has conducted for a 
basic model; therefore, there should not be a scenario in which a 
manufacturer has test results suggesting that the mean of the sample 
does not accurately reflect performance of the basic model, because 
those test results can be included in the sample. Thus, there would be 
no basis for a manufacturer to: (1) underrate cooling capacity (as 
compared to the mean of measured values) by more than 5 percent; or (2) 
overrate cooling capacity.
    Similar logic applies if a manufacturer develops ratings for a 
basic model based on AEDM simulations in accordance with 10 CFR 
429.43(a)(2). DOE's regulations at 10 CFR 429.70 provide a minimum 
number of tested models needed for validation of an AEDM, but if a 
manufacturer is concerned that the tested models do not reflect what is 
likely to be the ``average'' performance for those models given 
manufacturing variation and test variability, DOE does not limit the 
number of units or test chambers that can be used in the test results 
used to validate an AEDM. Therefore, similar to development of ratings 
via testing, for AEDM-simulated models, there would be no basis for a 
manufacturer to: (1) underrate cooling capacity (as compared to the 
AEDM-simulated values) by more than 5 percent; or (2) overrate cooling 
capacity.
    Consequently, DOE has concluded that the issues of manufacturing 
variation and test variability are sufficiently captured in DOE's 
existing regulations, so the Department is not adopting any wider 
tolerance on the represented cooling capacity than proposed. As such, 
DOE is adopting the provisions regarding representations of cooling 
capacity as originally proposed.
b. Verification of Cooling Capacity
    DOE currently outlines product-specific enforcement provisions at 
10 CFR 429.134(g) for ACUACs and ACUHPs, specifically that the mean of 
cooling capacity measurements during assessment or enforcement testing 
will be used to determine the applicable standards (which depend on 
cooling capacity) for purposes of compliance. First, DOE proposed in 
the August 2023 TP NOPR to expand the scope of this requirement to 
include ECUACs and WCUACs. 88 FR 56392, 56433 (August 17, 2023). 
Second, DOE proposed in the August 2023 TP NOPR for all CUACs and CUHPs 
that are the subject of this rulemaking that if the mean of the cooling 
capacity measurements exceeds by more than 5 percent the cooling 
capacity certified by the manufacturer, the mean of the measurement(s) 
will be used to select the applicable minimum ESP test condition from 
Table 7 of AHRI 340/360-2022 in appendix A or from Table 5 of the AHRI 
1340-202X Draft in appendix A1.\30\ Id.
---------------------------------------------------------------------------

    \30\ Table 5 of AHRI 1340-2023 includes the same ESP test 
conditions as Table 5 of the AHRI 1340-202X Draft.
---------------------------------------------------------------------------

    In the August 2023 TP NOPR, DOE requested comment on its proposal 
related to the verification testing of cooling capacity. Id. In 
response, Carrier and Trane disagreed with DOE's proposal to establish 
a 5-percent tolerance on rated capacity for determining the applicable 
minimum ESP condition when conducting verification testing. (Carrier, 
No. 8 at p. 4; Trane, No. 14 at p. 5)
    Trane asserted that this tolerance did not provide enough range for 
manufacturing, design, and testing variability. Trane also asserted 
that as a result of DOE's proposed 5-percent tested capacity limit 
above capacity ratings, in some cases, capacity ratings would be 
difficult to establish with the proposed approach because the tested 
capacity and ESP requirement continually impact each other in a way 
which would cause the tested capacity to be either too high or too low 
depending on the ESP applied. Trane provided an example illustrating 
the range of different capacities measured under different ESP 
conditions for the same model. Trane further asserted that there would 
be no benefit for manufacturers to conservatively rate units at lower 
ESPs due to capacity fluctuations because doing so could increase the 
minimum efficiency requirement and the resulting energy efficiency 
performance could be negatively impacted. (Trane, No. 14 at p. 5)
    Carrier argued that if manufacturers use the 5-percent margin in 
the certified capacity rating as the proposed rule allows, it is likely 
that the tested capacity during assessment and enforcement testing 
could go above the 105 percent tolerance, and, therefore, Carrier 
recommended that a tolerance of 10-percent be applied to the tested 
capacity. (Carrier, No. 8 at p. 4)
    Carrier also commented regarding an issue it found with the 
tolerance proposal due to the new ESP requirements in AHRI 1340. 
Carrier commented that the tested net capacity of a unit can decrease 
at higher static pressures due to heat loss from the electric motor 
operating against a higher static pressure. As such, Carrier commented 
that the tested capacity at lower static pressures could be above the 
test tolerance, but for the same unit at higher ESPs, the tested 
capacity could be below the test tolerances. Carrier requested further 
clarification from DOE as to which capacity should be used for ESP 
determination if this situation were to occur. (Id.)
    After careful consideration of comments received, DOE has concluded 
that the proposed provision to use the measured cooling capacity during 
assessment and enforcement testing to determine the ESP test condition 
if the measured cooling capacity exceeds the certified cooling capacity 
by more than 5 percent is not necessary at this time. As stated in the 
August 2023 TP NOPR, the intent of this proposal was to ensure the unit 
is being tested to the appropriate ESP and being evaluated against the 
appropriate standard during assessment and enforcement testing. 88 FR 
56392, 56433 (August 17, 2023). DOE has concluded that the adopted 
requirement (discussed in section III.G.1.a of this final rule) for the 
represented value of cooling capacity to be between 95 and 100 percent 
of the

[[Page 44022]]

mean of the total cooling capacities measured for the units in the 
sample (or between 95 and 100 percent of the AEDM-simulated cooling 
capacity) will ensure that the rated cooling capacity accurately 
reflects the cooling capacity for a basic model. Therefore, DOE has 
determined that maintaining the current policy of selecting the ESP 
requirement used for DOE testing based on the rated cooling capacity 
rather than the measured cooling capacity will provide a representative 
measure of the equipment's energy use. DOE acknowledges the issue 
raised by commenters, and notes that maintaining the current policy 
will prevent a situation in which the measured capacity iteratively 
affects the applicable ESP requirement, and will avoid any conflicts 
between DOE's enforcement provisions and DOE's adopted provisions 
allowing conservative rating of cooling capacity as low as 95 percent. 
As such, DOE is not adopting its proposal that the mean of measured 
capacities be used to select the applicable minimum ESP condition when 
it exceeds the rated cooling capacity of a basic model by more than 5 
percent.
    DOE did not receive comment regarding its proposal to expand the 
scope of the current product-specific enforcement requirements at 10 
CFR 429.134(g) to ECUACs and WCUACs. DOE has determined that extending 
this provision to ECUACs and WCUACs will ensure that the unit is being 
evaluated against the appropriate standard. As such, DOE is expanding 
the scope of the requirement at 10 CFR 429.134(g) that the mean of 
cooling capacity measurements will be used to determine the applicable 
standards (which depend on cooling capacity) for purposes of compliance 
to apply to ECUACs and WCUACs.
2. AEDM Tolerance for IVEC and IVHE
    As discussed previously, DOE's existing testing regulations allow 
the use of an AEDM, in lieu of testing, to simulate the efficiency of 
CUACs and CUHPs. 10 CFR 429.43(a). For models certified with an AEDM, 
results from DOE verification tests are subject to certain tolerances 
when compared to certified ratings. In the August 2023 TP NOPR, DOE 
proposed in table 2 to paragraph (c)(5)(vi)(B) at 10 CFR 429.70 to 
specify a tolerance of 10 percent for CUAC and CUHP verification tests 
for IVEC and IVHE. 88 FR 56392, 56434 (August 17, 2023). This tolerance 
is identical to the current tolerance specified for IEER (for ACUACs 
and ACUHPs) and for integrated metrics for other categories of 
commercial air conditioners and heat pumps (e.g., integrated seasonal 
coefficient of performance 2 and integrated seasonal moisture removal 
efficiency 2 for DX-DOASes). DOE also proposed to specify a tolerance 
of 5 percent for CUAC and CUHP verification testing for the optional 
EER2 and COP2 metrics. This tolerance is identical to the current 
tolerances specified for EER and COP for CUACs and CUHPs. Id.
    DOE did not receive any comments regarding this proposal. 
Therefore, DOE is adopting the AEDM tolerances applicable to IVEC, 
IVHE, EER2, and COP2 as proposed in the August 2023 TP NOPR.
3. Minimum Part-Load Airflow
    As previously discussed in sections III.D.1 and III.D.2 of this 
document, the IVEC and IVHE metrics account for energy consumed 
(specifically that of the indoor fan) in mechanical cooling and 
heating, as well as modes other than mechanical cooling and heating 
(e.g., economizer-only cooling, cooling season ventilation, heating 
season ventilation). IVEC and IVHE do not include separate tests or 
airflow rates for ventilation hours or economizer-only cooling (only 
applicable to IVEC). For example, for the economizer-only cooling hours 
in the D bin, the indoor fan power measured when operating at the 
lowest manufacturer-specified part-load airflow for a given load bin is 
applied for economizer-only cooling hours in that bin. Section 6.2.7 
and 6.3.10 of the AHRI 1340-202X Draft require that the lowest indoor 
fan power measured for cooling or heating tests is applied for cooling-
season ventilation hours in IVEC and heating-season ventilation hours 
in IVHE. AHRI 1340-2023 maintains these provisions. Therefore, 
considering mechanical cooling and heating, as well as other operating 
modes (e.g., economizer-only cooling, ventilation), the indoor fan 
power measured at the lowest manufacturer-specified part-load cooling 
and heating airflow rates represents a significant fraction of the 
power included in the IVEC and IVHE metrics (i.e., indoor fan power 
measured at these airflow rates is weighted by a significant number of 
hours), and differences in the lowest manufacturer-specified part-load 
airflow can significantly impact IVEC and IVHE ratings.
    Based on examination of publicly-available product literature, DOE 
understands that many basic models of a CUAC or CUHP have controls that 
allow for modulation of the minimum airflow used across a wide range of 
airflow turndown. DOE's research suggests that many models are 
distributed in commerce with an ``as-shipped'' minimum airflow and/or a 
default minimum airflow setting recommended in manufacturer 
installation instructions. However, in many cases, DOE observed that 
the unit controls allow the installer to change this minimum airflow 
setting during installation to reflect any constraints specific to a 
particular installation. DOE understands that such constraints may 
include the duct distribution system, the thermostat the CUAC or CUHP 
is paired with, and the minimum ventilation rate for the conditioned 
space served by the CUAC or CUHP. To ensure that IVEC and IVHE ratings 
reflect indoor fan power that is generally representative of airflow 
rates that would be used in the field for a given basic model, DOE 
considered the following two options for requirements related to 
minimum part-load airflow used for representations of IVEC and IVHE in 
the August 2023 TP NOPR:
    1. Representations of IVEC and IVHE (including IVHEc, as 
applicable) must be based on setting the lowest stage of airflow to the 
highest part-load airflow allowable by the basic model's system 
controls. For example, if fan control settings for a basic model allow 
its lowest stage of airflow to range from 40 to 60 percent, the basic 
model will need to be represented based on the lowest stage of airflow 
set to 60 percent of the full-load airflow.
    2. Representations of IVEC and IVHE (including IVHEc, as 
applicable) must be determined using minimum part-load airflow that is 
no lower than the highest of the following: (1) the minimum part-load 
airflow obtained using the as-shipped system control settings; (2) the 
minimum part-load airflow obtained using the default system control 
settings specified in the manufacturer installation instructions (as 
applicable); and (3) the minimum airflow rate specified in section 
5.18.2 of AHRI 1340-202X Draft.\31\ 88 FR 56392, 56434-56435 (August 
17, 2023).
---------------------------------------------------------------------------

    \31\ Section 5.18.2 of AHRI 1340-2023 includes the same 
provisions as those specified in section 5.18.2 of the AHRI 1340-
202X Draft.
---------------------------------------------------------------------------

    In the August 2023 TP NOPR, DOE tentatively concluded that option 
1, which requires representations based on the highest minimum part-
load airflow allowable by system controls, may result in 
unrepresentatively high airflow rates in cases in which a basic model 
allows configuration of minimum airflow to a very high percentage to 
accommodate a small fraction of installations in which minimum part-
load airflow must be high (e.g., in applications with very high minimum 
ventilation rates). Id.

[[Page 44023]]

Therefore, DOE proposed in the August 2023 TP NOPR to adopt option 2 
and requested comment on its proposal, as well as any alternate options 
not listed that would ensure representations of IVEC and IVHE are based 
on minimum part-load airflow that is representative of field 
installations. Id.
    AHRI, Carrier, Lennox, Rheem, and Trane opposed DOE's proposal and 
argued that the only restriction on minimum airflow rate should be what 
was agreed to in Recommendation #6 of the ACUAC and ACUHP Working Group 
TP Term Sheet (i.e., limiting the minimum airflow rate to that 
specified in Section 5.18.2 of the AHRI 1340-202X Draft). (AHRI, No. 15 
at pp. 6-7; Carrier, No. 8 at p. 5; Lennox, No. 9 at p. 3; Rheem, No. 
12 at p. 2; Trane No. 14 at p. 6) Carrier commented that the ACUAC and 
ACUHP Working Group TP Term Sheet includes a requirement for 
manufacturers to certify the airflow that is used in the lowest-stage 
cooling test, and stated that this ensures that the unit is capable of 
running in application at the airflows that were used in the tests or 
AEDM. Carrier further stated that restricting the broad range of 
airflow settings in commercial equipment to only those that are default 
from the factory is not appropriate and recommended that no further 
restrictions be placed on tested airflows beyond what was agreed upon 
in the ACUAC and ACUHP Working Group TP Term Sheet. (Carrier, No. 8 at 
p. 5)
    AHRI and Trane asserted that ratings are based on a representative 
average of many customer applications and that equipment built for 
stock has a default airflow and ESP with the expectation that customers 
will adjust and commission (i.e., adjust sheaves, VFDs, discharge air 
temperature setpoints, or other parts of the equipment) for their 
specific applications, and made-to-order equipment is built per 
customer specifications for a given installation. (AHRI, No. 15 at pp. 
6-7; Trane, No. 14 at p. 6) AHRI and Trane further stated that the 
default airflow and ESP may not align with the ESP requirements in the 
test procedure, and that considerable variation across installations 
does not align with a single rating point. (Id.) Trane further stated 
that equipment utilizing sheaves in the airflow system almost always 
require field adjustment up to and including different sheave 
components ordered as field-installed accessories to complete an 
equipment installation. (Trane, No. 14 at p. 6) AHRI and Trane further 
stated that supplemental test instructions submitted as part of 
certification ensure that the equipment is properly set up for any 
verification testing as per the test procedure. (AHRI, No. 15 at pp. 6-
7; Trane, No. 14 at p. 6)
    ASAP & ACEEE expressed support for DOE's proposal regarding 
determination of part-load airflow, stating that it improves 
representativeness by considering the default and as-shipped settings, 
and expressed concern that without DOE's proposal, manufacturers could 
rate models with airflows lower than would be representative. (ASAP & 
ACEEE, No. 11 at pp. 1-2)
    Regarding the comments that DOE should impose no additional 
requirements on minimum part-load airflow and that the only 
requirements should be the ones in the ACUAC/HP Working Group TP Term 
Sheet, DOE has concluded that the minimum part-load airflow 
requirements proposed for 10 CFR 429.43 have a different purpose than, 
and do not deviate from or conflict with, the requirement regarding 
minimum airflow specified in Recommendation #6 of the ACUAC and ACUHP 
Working Group TP Term Sheet (which is the minimum part-load airflow 
specified in section 5.18.2 of the AHRI 1340-202X Draft and AHRI 1340-
2023). In this final rule, DOE is adopting section 5.18.2 of AHRI 1340-
2023 in the test procedure at appendix A1, consistent with 
Recommendation #6 of the ACUAC and ACUHP Working Group TP Term Sheet. 
This minimum part-load airflow requirement from the Term Sheet and AHRI 
1340 represents the minimum airflow required to provide adequate 
ventilation in a typical building (based on an average of building 
types used to develop the IVEC metric, as discussed in section III.D.1 
of this document). In other words, the requirement in the test 
procedure is a lower bound on minimum airflow for any CUAC/HP model 
serving the average building, but it is not necessarily representative 
of the minimum part-load airflow used in the field for a given CUAC or 
CUHP model. For example, for a model that is typically installed with a 
minimum part-load airflow of 67 percent of full-load airflow, the 
minimum airflow limit specified in section 5.18.2 of AHRI 1340-2023 
would be far lower than that that representative minimum and would, 
therefore, fail to serve as a guardrail ensuring the minimum part-load 
airflow used for rating that model is representative of how the model 
is typically installed. DOE found in an examination of publicly-
available product literature, the range of airflows, including minimum 
part-load airflow, can differ between models based on application, 
design of the unit, and manufacturer preferences.
    As part of Working Group discussions regarding energy conservation 
standards, which occurred after the ACUAC and ACUHP Working Group TP 
Term Sheet was agreed to, it was discussed that minimum part-load 
airflow is one of the largest determinants of IVEC performance (see 
EERE-2022-BT-STD-0015-0092 at pp. 22-27). Specifically, during the 
course of the Working Group energy conservation standards negotiations, 
industry members in the ACUAC/HP Working Group provided a DOE 
contractor with a confidential, anonymized dataset that included 
simulated IEER and IVEC values for more than 100 models of CUACs and 
CUHPs currently available on the market. Analysis of this dataset 
indicated that the minimum part-load airflow is one of the most 
significant differentiators between models with lower and higher IVEC 
values. This is because, as discussed, the minimum part-load airflow is 
allocated to a large number of hours when calculating IVEC, so lower 
values of minimum part-load airflow are associated with higher values 
of IVEC. Given the Department's statutory obligation to ensure that 
ratings are based on a test procedure that is reasonably designed to 
produce test results which reflect energy efficiency during a 
representative average use cycle that is not unduly burdensome to 
conduct (42 U.S.C. 6314(a)(2)), DOE has concluded that provisions 
beyond those included in AHRI 1340-2023 are needed to ensure that the 
minimum part-load airflow used to determine IVEC is representative of 
how a given model is typically installed. Such provisions, when 
combined with the minimum airflow limit in AHRI 1340-2023 that DOE is 
also adopting in this final rule, would prevent use of an 
unrepresentatively low minimum part-load airflow that could boost 
efficiency ratings but not ultimately result in energy savings in the 
field. The provisions proposed by DOE address this issue by using the 
as-shipped or default values of minimum part-load airflow as indicators 
of the representative minimum part-load airflow used in the field. 
Although industry commenters objected to having additional requirements 
on the minimum part-load airflow, the objecting commenters apparently 
did not recognize the representativeness issue identified by DOE nor 
provide any alternate approaches to address the issue. In the absence 
of any suggested alternative approaches, DOE has determined that the 
proposed approach

[[Page 44024]]

is appropriate to ensure that the minimum part-load airflow used to 
determine IVEC is representative of field operation.
    Regarding comments from AHRI and Trane that ratings are based on a 
representative average of many customer applications and that 
considerable variation across installations does not align with a 
single rating point, DOE agrees that the test procedure is and should 
be based on a representative average of many applications. While this 
average rating inherently cannot perfectly represent every application, 
it should be representative of an average or typical installation. DOE 
disagrees that its proposed minimum part-load airflow provisions 
deviate from this ``representative average application'' approach 
underlying the test procedure. Without DOE's proposed provisions, there 
would be no mechanism constraining the certified minimum part-load 
airflow to be representative of how a given model is typically 
installed, and further, manufacturers would be incentivized to certify 
as low a minimum part-load airflow as possible in order to achieve a 
higher IVEC rating. DOE has concluded that the default or as-shipped 
minimum airflow setting is the best publicly-available proxy for what 
the most representative minimum part-load airflow is for a given model. 
DOE understands that many installers of CUACs and CUHPs do not change 
settings from their default and/or as-shipped values; therefore, DOE 
expects that manufacturers are incentivized to provide default and/or 
as-shipped minimum airflow values that are appropriate for and 
representative of a typical installation. DOE understands that that 
some applications may have lower minimum part-load airflows than 
provided by the default settings, but has concluded that the default or 
as-shipped minimum part-load airflow settings are representative of a 
typical installation. Additionally, the default airflow setting for a 
specific model is not a single rating condition for all models (such as 
an ESP requirement or test condition)--it instead reflects whatever 
model-specific considerations the manufacturer might use to determine 
the default or as-shipped minimum part-load airflow for the model.
    Additionally, DOE notes that several of the concerns expressed by 
commenters do not apply to DOE's proposal. Specifically, concerns 
expressed regarding the adjustment of sheaves and whether the default 
airflow settings are compatible with the airflow and ESP requirements 
in the test procedure are not relevant to the proposal, because DOE's 
proposal only addresses part-load airflow. For CUACs and CUHPs with 
adjustable sheaves, the sheaves are adjusted when installing the unit 
to ensure the fan drive assembly is providing the appropriate airflow 
for a given installation. Similarly, sheaves are typically adjusted as 
part of test set-up for the full-load cooling test to meet the full-
load airflow and ESP test requirements withing tolerance. However, 
sheaves are not adjusted between full-load and part-load operation, and 
are, therefore, not relevant to this proposal. Similarly, DOE 
recognizes that the default full-load airflow settings may not be 
compatible with the airflow and ESP requirements in the test procedure, 
but DOE has proposed no restrictions on the certified full-load 
airflow. In summary, DOE's proposal does not have any effect on the fan 
control settings used to achieve the full-load airflow and ESP used for 
testing. DOE's proposal only affects the minimum part-load airflow for 
testing, which is a percentage of the full-load airflow already 
achieved in the full-load cooling test, not an absolute value. Part-
load airflow is typically reduced by lowering the power provided to the 
fan motor by a VFD (relative to the power provided for full-load 
cooling), an adjustment that it made automatically in field 
installations but can be manually programmed during test. Therefore, 
regardless of how different the fan control settings needed to achieve 
the full-load airflow and ESP used for testing may be from the default 
or as-shipped full-load airflow settings, DOE has concluded that the 
default or as-shipped minimum part-load airflow settings provide an 
appropriate and representative degree of airflow turndown that will 
allow for meeting all test tolerances.
    Regarding comments by AHRI and Trane that supplemental test 
instructions indicate how units should be set up for test, DOE notes 
that supplemental test instructions are used to ensure that DOE testing 
is performed consistent with how the manufacturer rated the equipment. 
Supplemental test instructions do not ensure that manufacturer-
specified settings are representative of field use for a basic model. 
Similarly, the manufacturer's certification of the minimum airflow used 
for ratings of a basic model (which was cited by Carrier) does not 
ensure that the certified airflow is representative of field use. The 
provisions proposed in 10 CFR 429.43 for minimum part-load airflow, 
however, are intended to ensure that manufacturer-specified and 
certified minimum part-load airflows are representative of field use.
    For the reasons discussed in the previous paragraphs, DOE is 
adopting the proposed provisions for minimum airflow in 10 CFR 429.43. 
DOE is not amending certification requirements for CUACs and CUHPs in 
this rulemaking, but DOE will consider such amendments in a separate 
rulemaking for certification, compliance, and enforcement. As part of 
that rulemaking, DOE will consider certification requirements 
pertaining to this minimum airflow issue, such as requiring 
certification of the range of minimum part-load airflow allowed by 
system controls for each basic model.

H. Enforcement Procedure for Verifying Cut-In and Cut-Out Temperatures

    Recommendation #10 of the ACUAC and ACUHP Working Group TP Term 
Sheet states that DOE will adopt product-specific enforcement 
provisions for ACUHPs that include a method to verify certified cut-out 
and cut-in temperatures based on the test method outlined in the 
Residential Cold-Climate Heat Pump Technology Challenge (``CCHP 
Challenge'').\32\ The docketed AHRI 1340-202X Draft did not include 
test provisions for verifying cut-in and cut-out temperatures, but in 
the August 2023 TP NOPR, DOE proposed to adopt a method for verifying 
certified cut-out and cut-in temperatures at 10 CFR 429.134(g) 
consistent with Recommendation #10 of the ACUAC and ACUHP Working Group 
TP Term Sheet. 88 FR 56392, 56435 (August 17, 2023). Specifically, 
consistent with the CCHP Challenge method and the ACUAC and ACUHP 
Working Group TP Term Sheet, the proposed method specified gradually 
ramping down outdoor air temperature until the unit cuts out and 
gradually ramping back up outdoor air temperature until the unit cuts 
back on, with the temperature ramp-up and ramp-down conducted at 1.0 
[deg]F every 5 minutes. DOE did not receive any comments on its 
proposed method for verifying cut-in and cut-out temperatures.
---------------------------------------------------------------------------

    \32\ See www.energy.gov/sites/default/files/2021-10/bto-cchp-tech-challenge-spec-102521.pdf.
---------------------------------------------------------------------------

    Appendix H of AHRI 1340-2023 includes a procedure for verifying 
cut-in and cut-out temperatures that is generally consistent with the 
procedure proposed in the August 2023 TP NOPR. As such, and consistent 
with Recommendation #10 of the ACUAC and ACUHP Working Group TP Term 
Sheet, DOE is adopting this procedure for verifying certified cut-in 
and cut-out temperatures through reference to

[[Page 44025]]

appendix H of AHRI 1340-2023 in DOE's product-specific enforcement 
provisions at 10 CFR 429.134(g). DOE will address certification 
requirements for CUACs and CUHPs, including the potential requirement 
for certification of cut-out and cut-in temperatures, in a separate 
rulemaking for certification, compliance, and enforcement.

I. Organization of the Regulatory Text for CUACs and CUHPs

    In addition to the substantive changes discussed previously in this 
document, DOE proposed organizational changes to table 1 to 10 CFR 
431.96(b) and tables 1 through 6 to 10 CFR 431.97 in the August 2023 TP 
NOPR that were not substantive and were intended to reflect terminology 
changes and to improve the overall readability of the tables. 88 FR 
56392, 56435-56436 (August 17, 2023).
    Specifically, in table 1 to 10 CFR 431.96(b) (regarding test 
procedures for commercial air conditioners and heat pumps), DOE 
proposed to revise terminology to reflect the proposed definition for 
``commercial unitary air conditioners with a rated cooling capacity 
greater than or equal to 65,000 Btu/h (CUACs) and commercial unitary 
heat pumps with a rated cooling capacity greater than or equal to 
65,000 Btu/h (CUHPs),'' discussed further in section III.B.1 of this 
final rule. Id.
    Additionally, tables 1 through 5 to 10 CFR 431.97 currently specify 
cooling and heating standards for CUACs, CUHPs, and water-source heat 
pumps (``WSHPs''). DOE also proposed to revise this terminology to 
reflect the proposed definition for CUACs and CUHPs, remove outdated 
standards no longer in effect, combine cooling and heating standards 
into the same tables, and create separate tables for standards for 
ACUACs and ACUHPs (in Table 1), WCUACs (in Table 2), ECUACs (in Table 
3), double-duct systems (in Table 4), and WSHPs (in Table 5). Id.
    DOE did not receive comment in response to the August 2023 TP NOPR 
with respect to the proposed organization of regulatory text for CUACs 
and CUHPs. DOE has determined that these changes will improve the 
overall readability of the tables in 10 CFR 431.96 and 431.97 and are 
consistent with the other changes adopted in this final rule. However, 
as discussed in section III.B.1, DOE is not finalizing the proposed 
definition for CUAC and CUHP. As such, DOE is not implementing the 
proposed changes in 10 CFR 431.96 and 431.97 to reflect the proposed 
term for CUAC and CUHP. Other than these terminology changes, DOE is 
adopting its proposed reorganization of regulatory text for CUACs and 
CUHPs in this final rule.

J. Effective and Compliance Dates

    The effective date for the adopted test procedure amendments will 
be 75 days after the date of publication of this final rule in the 
Federal Register. EPCA prescribes that all representations of energy 
efficiency and energy use, including those made on marketing materials 
and product labels, must be made in accordance with an amended test 
procedure, beginning 360 days after the date of publication of the 
final rule in the Federal Register. (42 U.S.C. 6314(d)(1)) To the 
extent the modified test procedure adopted in this final rule is 
required only for the evaluation and issuance of updated efficiency 
standards, compliance with the amended test procedure does not require 
use of such modified test procedure provisions until the compliance 
date of updated standards.

K. Test Procedure Costs and Impact

    EPCA requires that the test procedures for commercial package air 
conditioning and heating equipment, which includes CUACs and CUHPs, be 
those generally accepted industry testing procedures or rating 
procedures developed or recognized by either AHRI or ASHRAE, as 
referenced in ASHRAE Standard 90.1. (42 U.S.C. 6314(a)(4)(A)) Further, 
if such an industry test procedure is amended, DOE must amend its test 
procedure to be consistent with the amended industry test procedure, 
unless DOE determines, by rule published in the Federal Register and 
supported by clear and convincing evidence, that such an amended test 
procedure would not meet the requirements in 42 U.S.C. 6314(a)(2)-(3) 
related to representative use and test burden. (42 U.S.C. 
6314(a)(4)(B))
    In this final rule, DOE is revising the existing test procedure for 
CUACs and CUHPs (consolidating for ACUACs and ACUHPs, ECUACs, and 
WCUACs) at appendix A and adopting an amended test procedure at 
appendix A1. These adoptions are discussed in the following sub-
sections. DOE has also amended its representation and enforcement 
provisions for CUACs and CUHPs.
1. Appendix A
    In this final rule, DOE has amended the existing Federal test 
procedure for CUACs and CUHPs (including double-duct systems), which is 
currently located at appendix A for ACUACs and ACUHPs and 10 CFR 431.96 
for ECUACs and WCUACs. Specifically, DOE consolidated the test 
procedures for ACUACs and ACUHPs, ECUACs, and WCUACs at appendix A and 
updated the test procedure to incorporate by reference an updated 
version of the applicable industry test method, AHRI 340/360-2022. The 
revisions to appendix A retain the current efficiency metrics (i.e., 
EER, IEER, and COP). The testing requirements in appendix A are 
generally consistent with those in AHRI 340/360-2022, which in turn 
references ANSI/ASHRAE 37-2009. This is generally consistent with the 
industry test procedures referenced in the latest version of ASHRAE 
Standard 90.1.
    DOE has determined that the amendments to appendix A will improve 
the representativeness, accuracy, and reproducibility of the test 
results and will not be unduly burdensome for manufacturers to conduct 
or result in increased testing cost as compared to the current test 
procedure. The revisions to the test procedure in appendix A for 
measuring EER, IEER, and COP per AHRI 340/360-2022 will not increase 
third-party laboratory testing costs per unit relative to the current 
DOE test procedure. DOE estimates the current costs of physical testing 
to the current required metrics to be $10,500 for ACUACs, $12,000 for 
ACUHPs, $6,800 for double-duct air conditioners, $8,300 for double-duct 
heat pumps, and $6,800 for ECUACs and WCUACs. Further, DOE has 
concluded that the adopted revisions to the test procedure in appendix 
A will not change efficiency ratings for CUACs and CUHPs, and, 
therefore, will not require retesting solely as a result of DOE's 
adoption of this amendment to the DOE test procedure.\33\
---------------------------------------------------------------------------

    \33\ Manufacturers are not required to perform laboratory 
testing on all basic models. In accordance with 10 CFR 429.70, CUAC 
and CUHP manufacturers may elect to use AEDMs. An AEDM is a computer 
modeling or mathematical tool that predicts the performance of non-
tested basic models. These computer modeling and mathematical tools, 
when properly developed, can provide a means to predict the energy 
usage or efficiency characteristics of a basic model of a given 
covered product or equipment and to reduce the burden and cost 
associated with testing.
---------------------------------------------------------------------------

2. Appendix A1
    In the August 2023 TP NOPR, DOE proposed to amend the existing test 
procedure for CUACs and CUHPs (including double-duct equipment) by 
adopting a new appendix A1 that references AHRI 1340-202X Draft, 
including the IVEC and IVHE energy efficiency metrics. DOE noted that 
the proposed test procedure in appendix A1 would lead to an increase in 
test cost from the current Federal test procedure; therefore, DOE 
presented estimates of

[[Page 44026]]

the test costs associated with the proposed test procedure in appendix 
A1. 88 FR 56392, 56436-56437 (August 17, 2023). The proposed test cost 
estimates are presented in Table III-6. DOE requested comments 
regarding its tentative understanding of the impact of the proposals in 
the NOPR, particularly regarding DOE's initial estimate of the cost 
impacts associated with appendix A1. Id.
    Carrier commented that the test cost estimates presented in the 
NOPR are likely incorrect, as there is a substantial difference in set-
up time and the amount of energy required to test from the smallest 
systems to the largest. (Carrier, No. 8 at p. 5)
    Trane expressed concerns regarding the cost estimate for the 5 
[deg]F optional test, and the commenter argued that testing to these 
low temperatures would require significant capital investment on the 
part of certification laboratories, as well as increased time to 
conduct testing at low temperature conditions due to the need for more 
frequent defrosting of the facility. (Trane, No. 14 at pp. 6-7) 
Specifically, Trane stated the test cost for the optional 5 [deg]F test 
should be closer to $9,600 (representing four additional shifts in the 
test laboratory) rather than the $2,000-$4,000 additional cost 
estimated in the NOPR. Id.
    In this final rule, DOE is amending the existing test procedure for 
CUACs and CUHPs (including double-duct equipment) by adopting a new 
appendix A1 that utilizes the most recent version of the applicable 
industry consensus test procedure, AHRI 1340-2023, including the IVEC 
and IVHE energy efficiency metrics. Should DOE adopt standards in a 
future energy conservation standards rulemaking denominated in terms of 
the new metrics, the test procedure in appendix A1 (which references 
AHRI 1340-2023) would be required.
    In light of the comments received, DOE once again considered the 
estimated costs and burdens associated with the new appendix A1. For 
the reasons that follow, DOE determined these costs to have remained 
largely the same as those presented in the August 2023 TP NOPR, with 
just a few adjustments.
    DOE has determined that these amendments will be representative of 
an average use cycle and will not be unduly burdensome for 
manufacturers to conduct. The test procedure in appendix A1 will lead 
to an increase in test cost from the current Federal test procedure, as 
discussed in the following paragraphs. The following paragraphs include 
estimates for increases in cost of testing at a third-party laboratory.
    The change in ESP requirements discussed in section III.D.1 that 
apply to measuring the IVEC and IVHE metrics will require additional 
test set-up that DOE expects will increase test costs. DOE has 
concluded that metal ductwork will need to be fabricated for testing to 
withstand the higher ESP requirements (as compared to foamboard 
ductwork typically used for testing to the current test procedure). DOE 
estimates a test cost increase ranging from $500 to $1,500 per unit, 
depending on the unit size/cooling capacity, associated with this 
transition to metal ductwork. To meet the return/supply duct ESP 
requirement, DOE estimates an increase of $200 per unit for the time 
required to apply return duct restrictions. In combination, DOE 
estimates a total test cost increase of between $700 and $1,700 per 
unit to meet the new ESP requirements.
    For determining IVEC, DOE has concluded that there will not be an 
increase in testing cost as compared to measuring IEER per the current 
Federal test procedure, beyond the costs associated with the new ESP 
requirements discussed previously.
    For determining IVHE, there are two required heating tests and 
several additional optional heating tests. The required heating tests 
are full-load tests at 47 [deg]F and 17 [deg]F. The full-load test at 
47 [deg]F is already required for the current Federal test procedure 
for determining COP. The full-load test at 17 [deg]F is currently 
required for the AHRI certification program. Because all identified 
CUHP manufacturers are AHRI members and participate in the AHRI 
certification program and because third-party laboratories currently 
have the capability to perform these tests, DOE expects that that the 
required heating tests for IVHE will not increase test cost as compared 
to testing that is typically already conducted, beyond the costs 
associated with the new ESP requirements discussed previously.
    Optional heating tests for CUHPs will increase the cost of heating 
testing if conducted. The optional tests for IVHE are outlined in 
III.D.2 of this final rule, which include: (1) an additional full-load 
test at 5 [deg]F; (2) part-load tests at 17 [deg]F and 47 [deg]F 
(including up to 2 part-load tests at each temperature); and (3) for 
variable-speed units, boost tests at 17 [deg]F and 5 [deg]F. DOE 
estimates that each optional test conducted will increase the cost of 
heating testing by $2,000 to $4,000 depending on the test condition.
    Regarding Trane's comments on burden of the optional 5 [deg]F test, 
DOE disagrees that conducting a heating test for CUHPs would cost as 
much as $9,600 at third-party laboratories. DOE expects Trane's 
estimate may be referring to test facilities that are not designed for 
low-temperature testing. However, DOE is aware of multiple third-party 
laboratories commonly used by the CUAC and CUHP industry for testing 
that have test chambers that can already achieve the 5 [deg]F test 
condition in much less time than would warrant four shifts. Further, 
DOE notes that it has received a test quote from a third-party 
laboratory for conducting the 5 [deg]F test that is within the range of 
test costs estimated in the August 2023 TP NOPR. Therefore, DOE 
maintains its estimate of $2,000 to $4,000 for each optional heating 
test. DOE reiterates that these tests are optional, and, thus, the test 
procedure adopted in this final rule will not require any manufacturers 
to conduct a 5 [deg]F test.
    For ECUACs, WCUACs, and double-duct systems, the current Federal 
test procedure requires testing to EER for cooling tests; testing to 
IEER is not currently required for ECUACs, WCUACs, or double-duct 
systems. Because measuring EER requires only a single test, DOE expects 
that measuring IVEC for ECUACs, WCUACs, and double-duct systems will 
increase the cost of cooling testing. Specifically, DOE estimates the 
cost of additional cooling tests to be $3,700 per unit. Further, the 
previously discussed costs associated with the new indoor air ESP 
requirements ($700 to $1,700 depending on unit size) will also apply to 
ECUACs, WCUACs, and double-duct systems. In addition, for double-duct 
systems DOE expects that testing to appendix A1 will require an 
additional $2,000 per unit for set-up to meet the non-zero outdoor air 
ESP requirement. Otherwise, DOE expects similar test burden for 
determining IVHE for double-duct systems as for determining IVHE for 
conventional ACUHPs, as discussed in the preceding paragraphs.
    Regarding Carrier's comment about the burden of testing higher-
capacity equipment, DOE acknowledges that there may be higher third-
party laboratory test costs associated with test set-up for larger 
units than for smaller units. Accordingly, DOE estimates that up to an 
additional shift (which DOE estimates to cost approximately $2,600) may 
be necessary for test set-up for the largest covered basic models, and 
the Department has adjusted the upper bound of its estimated test cost 
range accordingly.
    Table III-6 shows DOE's estimates for testing to the current 
Federal test procedure and the test procedure in appendix A1.

[[Page 44027]]

[GRAPHIC] [TIFF OMITTED] TR20MY24.133

    In the August 2023 TP NOPR, DOE also estimated the cost to develop 
and validate an AEDM for determining IVEC (and IVHE as applicable) for 
CUACs and CUHPs (including double-duct systems) to be $19,000 per AEDM. 
Once the AEDM is developed, DOE estimated that it would take one hour 
of an engineer's time (calculated based upon an engineering technician 
wage of $41 per hour) to determine efficiency for each basic model 
using the AEDM. 88 FR 56392, 56437 (August 17, 2023).
    AHRI, Carrier, Trane, and Rheem commented that the proposed cost to 
develop an AEDM to rate units to the new IVEC and IVHE metrics were 
greatly underestimated in the NOPR. (AHRI, No. 15 at p. 7; Carrier, No. 
8 at p. 5; Trane, No. 14 at pp. 6-7; Rheem, No. 12 at p. 3) Carrier 
stated that to lower potential risk of failure or product availability 
associated with an AEDM issue, manufacturers typically test more than 
the minimum two units required for AEDM validation, and manufacturers 
develop multiple AEDMs to limit the number of basic models for which 
each AEDM was used to generate ratings. (Carrier, No. 8 at p. 5) AHRI 
and Trane stated that manufacturers may test significantly more units 
than the two required by DOE to validate an AEDM. (AHRI, No. 15 at p. 
7; Trane, No. 14 at pp. 6-7) Rheem stated that the adoption of appendix 
A1 will require significant investment by manufacturers for product 
development, laboratory upgrades, and additional testing. (Rheem, No. 
12 at p. 3)
    In response, DOE notes that most CUAC/HP manufacturers have in-
house testing capabilities and would principally use those resources 
for required testing. DOE expects in-house testing to be cheaper on a 
per-test basis than third-party testing. DOE is conservatively 
presenting costs associated with a scenario where a manufacturer does 
not have these in-house testing resources, or where those resources are 
otherwise occupied and the manufacturer has to rely on third-party 
testing. Apart from the optional heating tests, DOE has concluded that 
the amended test procedures adopted in this final rule would not 
require capital improvements to in-house testing facilities. (DOE once 
again notes that the 5 [deg]F test, which some manufacturer's test 
chambers may need upgrades to conduct, is optional.) Further, the 
amended test procedures will not require manufacturers to undergo any 
new product development. Any burden associated with model redesign to 
meet amended energy conservation standards would be addressed in a 
separate standards rulemaking.
    As discussed, DOE has concluded that that the potential adoption of 
amended energy conservation standards denominated in terms of IVEC and 
IVHE (and corresponding requirement to use the adopted test procedure 
in appendix A1) would alter the measured energy efficiency of CUACs and 
CUHPs. Consequently, manufacturers would not be able to rely on data 
generated under the current test procedure and would, therefore, be 
required to re-rate CUAC and CUHP models. In accordance with 10 CFR 
429.70, however, CUAC and CUHP manufacturers may elect to use AEDMs to 
rate models, which significantly reduces costs to industry. DOE has 
updated its estimate of AEDM creation costs to reflect both the 
previously mentioned modest increase in labor time associated with 
testing of large units and the cost range of physical testing broadly. 
In this final rule, DOE estimates the total cost to develop and 
validate an AEDM for determining IVEC (and IVHE as applicable) for 
CUACs and CUHPs (including double-duct systems) to be between $26,400 
and $40,600 per AEDM.\34\ Once the AEDM is developed, DOE estimates 
that it will take one hour of an engineer's time (calculated based upon 
a fully burdened engineering technician wage of $41.52 per hour) to

[[Page 44028]]

determine efficiency for each basic model using the AEDM.
---------------------------------------------------------------------------

    \34\ DOE estimates that a technician would need 80 hours to 
develop an AEDM and 16 hours to validate an AEDM based on testing, 
and that the tests of two basic models would be required per AEDM. 
At a fully burdened labor rate of $41.52 per hour, the cost to 
develop and validate an AEDM would be approximately $4,000 and the 
cost to carry out the testing would be between $11,200 and $18,300 
for each basic model, depending on the equipment category of models 
tested. Therefore, DOE estimates that total AEDM creation costs 
would be between $26,400 and $40,600.
---------------------------------------------------------------------------

    In accordance with 10 CFR 429.70, manufacturers rating their CUAC 
and CUHP models with AEDMs must validate an AEDM with testing of a 
minimum of two basic models per validation class (see 10 CFR 
429.70(c)(2)(iv)). DOE acknowledges that manufacturers may choose to 
test more models than the minimum required by DOE, but DOE has 
estimated burden associated with what would be required by its amended 
regulations, not including additional testing manufacturers might 
choose to undertake at their discretion. Accordingly, in this final 
rule, DOE maintains a cost estimate for AEDM development based on 
testing test two basic models for each AEDM.

IV. Procedural Issues and Regulatory Review

A. Review Under Executive Orders 12866, 13563, and 14094

    Executive Order (``E.O.'') 12866, ``Regulatory Planning and 
Review,'' 58 FR 51735 (Oct. 4, 1993), as supplemented and reaffirmed by 
E.O. 13563, ``Improving Regulation and Regulatory Review,'' 76 FR 3821 
(Jan. 21, 2011), and E.O. 14094, ``Modernizing Regulatory Review,'' 88 
FR 21879 (April 11, 2023), requires agencies, to the extent permitted 
by law, to: (1) propose or adopt a regulation only upon a reasoned 
determination that its benefits justify its costs (recognizing that 
some benefits and costs are difficult to quantify); (2) tailor 
regulations to impose the least burden on society, consistent with 
obtaining regulatory objectives, taking into account, among other 
things, and to the extent practicable, the costs of cumulative 
regulations; (3) select, in choosing among alternative regulatory 
approaches, those approaches that maximize net benefits (including 
potential economic, environmental, public health and safety, and other 
advantages; distributive impacts; and equity); (4) to the extent 
feasible, specify performance objectives, rather than specifying the 
behavior or manner of compliance that regulated entities must adopt; 
and (5) identify and assess available alternatives to direct 
regulation, including providing economic incentives to encourage the 
desired behavior, such as user fees or marketable permits, or providing 
information upon which choices can be made by the public. DOE 
emphasizes as well that E.O. 13563 requires agencies to use the best 
available techniques to quantify anticipated present and future 
benefits and costs as accurately as possible. In its guidance, the 
Office of Information and Regulatory Affairs (``OIRA'') in the Office 
of Management and Budget (``OMB'') has emphasized that such techniques 
may include identifying changing future compliance costs that might 
result from technological innovation or anticipated behavioral changes. 
For the reasons stated in the preamble, this final regulatory action is 
consistent with these principles.
    Section 6(a) of E.O. 12866 also requires agencies to submit 
``significant regulatory actions'' to OIRA for review. OIRA has 
determined that this final regulatory action does not constitute a 
``significant regulatory action'' under section 3(f) of E.O. 12866, as 
amended by E.O. 14094. Accordingly, this action was not submitted to 
OIRA for review under E.O. 12866.

B. Review Under the Regulatory Flexibility Act

    The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires 
preparation of an initial regulatory flexibility analysis (``IRFA'') 
and a final regulatory flexibility analysis (``FRFA'') for any rule 
where the agency was first required by law to publish a proposed rule 
for public comment, unless the agency certifies that the rule, if 
promulgated, will not have a significant economic impact on a 
substantial number of small entities. As required by Executive Order 
13272, ``Proper Consideration of Small Entities in Agency Rulemaking,'' 
67 FR 53461 (August 16, 2002), DOE published procedures and policies in 
the Federal Register on February 19, 2003, to ensure that the potential 
impacts of its rules on small entities are properly considered during 
the DOE rulemaking process. 68 FR 7990. DOE has made its procedures and 
policies available on the Office of the General Counsel's website: 
www.energy.gov/gc/office-general-counsel. DOE reviewed this final rule 
under the provisions of the Regulatory Flexibility Act and the 
procedures and policies published on February 19, 2003.
    The following sections explain DOE's determination that this final 
rule does not have a ``significant economic impact on a substantial 
number of small entities,'' and that the preparation of a FRFA is not 
warranted.
1. Estimate of Small Entities Regulated
    For manufacturers of CUACs and CUHPs, the Small Business 
Administration (``SBA'') has set a size threshold, which defines those 
entities classified as ``small businesses'' for the purposes of the 
statute. DOE used the SBA's small business size standards to determine 
whether any small entities would be subject to the requirements of the 
rule. See 13 CFR part 121. The equipment covered by this rule is 
classified under North American Industry Classification System 
(``NAICS'') code 333415,\35\ ``Air-Conditioning and Warm Air Heating 
Equipment and Commercial and Industrial Refrigeration Equipment 
Manufacturing.'' In 13 CFR 121.201, the SBA sets a threshold of 1,250 
employees or fewer for an entity to be considered as a small business 
for this category.
---------------------------------------------------------------------------

    \35\ The size standards are listed by NAICS code and industry 
description and are available at www.sba.gov/document/support--table-size-standards (last accessed April 4, 2023).
---------------------------------------------------------------------------

    DOE reviewed the test procedures adopted in this final rule under 
the provisions of the Regulatory Flexibility Act and the procedures and 
policies published on February 19, 2003. DOE utilized DOE's Compliance 
Certification Database (``CCD'') \36\ and manufacturer websites to 
identify potential small businesses that manufacture CUACs and CUHPs 
covered by this rulemaking. DOE identified 13 companies that are 
original equipment manufacturers (``OEMs'') of CUACs and CUHPs covered 
by this rulemaking. Next, DOE screened out companies that do not meet 
the definition of a ``small business'' or are foreign-owned and 
operated. Ultimately, for this final rule DOE identified two small, 
domestic OEMs for consideration. DOE's assessment indicates that of 
these two OEMs, one is an AHRI member, and one is not an AHRI member 
and does not certify their equipment in the AHRI Directory. DOE used 
subscription-based business information tools (e.g., reports from Dun & 
Bradstreet) \37\ to determine headcount and revenue of each small 
business.
---------------------------------------------------------------------------

    \36\ Certified equipment in the CCD is listed by equipment class 
and can be accessed at www.regulations.doe.gov/certification-data/#q=Product_Group_s%3A* (last accessed Dec. 16, 2023).
    \37\ Market research is available through the Dun & Bradstreet 
Hoovers login page at: app.dnbhoovers.com (last accessed April 3, 
2023).
---------------------------------------------------------------------------

2. Description and Estimate of Compliance Requirements
    In this final rule, DOE is revising the existing test procedure for 
CUACs and CUHPs (consolidating for ACUACs and ACUHPs, ECUACs, and 
WCUACs) at appendix A of subpart F of part 431 (appendix A) by adopting 
sections of AHRI 340/360-2022. DOE is also amending the test procedure 
for CUACs and CUHPs by adopting a new appendix A1 to subpart F of part 
431 (``appendix A1'') that references the industry test

[[Page 44029]]

standard AHRI 1340-2023. Additionally, this final rule amends the 
representation and enforcement provisions for CUACs and CUHPs in 10 CFR 
part 429 and certain definitions for CUACs and CUHPs in 10 CFR part 
431. Specific cost and compliance associated with each appendix are 
discussed in the subsections that follow.
a. Cost and Compliance Associated With Appendix A
    In appendix A, DOE has amended the existing test procedure for 
CUACs and CUHPs (relocated to appendix A for ECUACs and WCUACs, for 
which the current test procedure is located at 10 CFR 431.96) by 
incorporating by reference an updated version of the applicable 
industry test method, AHRI 340/360-2022, which includes the energy 
efficiency metrics IEER (required metric for ACUACs and ACUHPs), EER 
(required metric for ECUACs, WCUACs, and double-duct systems), and COP 
(required metric for ACUHPs and double-duct heat pumps) and maintaining 
an existing reference to industry test method ANSI/ASHRAE 37-2009. The 
adopted test procedure at appendix A does not change efficiency ratings 
as compared to the current Federal test procedure, and, therefore, will 
not require retesting nor increase third-party laboratory testing costs 
per unit solely as a result of DOE's adoption of this amendment to the 
test procedure. DOE estimates the current costs of physical testing to 
the current required metrics to be: $10,500 for ACUACs; $12,000 for 
ACUHPs; $6,800 for double-duct air conditioners; $8,300 for double-duct 
heat pumps; and $6,800 for ECUACs and WCUACs. In accordance with 10 CFR 
429.70, CUAC and CUHP manufacturers may elect to use AEDMs to rate 
models, an approach which can significantly reduce costs to industry.
b. Cost and Compliance Associated With Appendix A1
    In appendix A1, DOE is adopting the test conditions and procedures 
in AHRI 1340-2023 and ANSI/ASHRAE 37-2009. The test procedure in 
appendix A1 includes provisions for measuring CUAC and CUHP energy 
efficiency using the IVEC and IVHE metrics so as to be consistent with 
the updated industry test procedure. Should DOE adopt amended energy 
conservation standards in the future denominated in terms of IVEC and 
IVHE, the Department expects there would be an increase in third-party 
laboratory testing cost relative to the current Federal test procedure, 
as outlined in further detail in section III.K.2 of this document. 
Table IV-1 shows DOE's estimates for testing to the current Federal 
test procedure, the initial cost estimate associated with the NOPR, and 
this final rule's cost estimate for the adopted test procedure in 
appendix A1.
[GRAPHIC] [TIFF OMITTED] TR20MY24.134

    If CUAC and CUHP manufacturers conduct physical testing to certify 
a basic model, two units are required to be tested per basic model. 
However, manufacturers are not required to perform laboratory testing 
on all basic models, as manufacturers may elect to use AEDMs, in 
accordance with 10 CFR 429.70. An AEDM is a computer modeling or 
mathematical tool that predicts the performance of non-tested basic 
models. These computer modeling and mathematical tools, when properly 
developed, can provide a means to predict the energy usage or 
efficiency characteristics of a basic model of a given covered product 
or equipment and reduce the burden and cost associated with testing.
    Small businesses would be expected to have different potential 
regulatory costs depending on whether they are a member of AHRI. DOE 
understands that all AHRI members and all manufacturers currently 
certifying to the AHRI Directory will be testing their CUAC and CUHP 
models in accordance with AHRI 1340-2023, the industry test procedure 
DOE is adopting, and using AHRI's certification program.
    The adopted test procedure amendments will not add any additional 
testing burden to manufacturers which are members of AHRI. As 
discussed, DOE identified one small, domestic OEM that is an AHRI

[[Page 44030]]

member. Therefore, DOE has concluded that the adopted test procedure 
amendments will not add additional testing burden to one of the two 
identified small, domestic OEMs, as that AHRI member company will soon 
be using AHRI 1340-2023. DOE estimated the potential impacts for the 
one identified small, domestic OEM that is not an AHRI member and does 
not certify their equipment in the AHRI Directory. This small business 
would only incur additional costs if the company would not otherwise be 
using the AHRI 1340-2023 test procedure to rate their models of CUACs 
and CUHPs.
    DOE estimates that this non-AHRI member company manufactures 14 
basic models of ECUACs and WCUACs. To develop cost estimates for this 
small business, DOE considered the cost to develop an AEDM, the costs 
to validate the AEDM through physical testing, and the cost per model 
to determine ratings using the AEDM. DOE anticipates that this small 
OEM would avail itself of the cost-saving option which the AEDM 
provides. DOE estimated the cost to develop an AEDM for ECUACs or 
WCUACs to be $33,600 per AEDM, which includes the required physical 
testing of two basic models per validation class. Because ECUACs and 
WCUACs are separate validation classes (per 10 CFR 429.70), the 
manufacturer would require two AEDMs--one for ECUACs and one for 
WCUACs, for a total AEDM development cost of $67,200. Additionally, DOE 
estimated a cost of $41.52 per basic model for determining energy 
efficiency using the validated AEDM. The estimated cost to rate the 14 
basic models with the AEDM would be approximately $600.
    Therefore, total testing and rating costs expected for this small 
business, when and if DOE adopts amended energy conservation standards 
for ECUACs and WCUACs denominated in terms of the IVEC metric, would be 
approximately $67,800 for the two AEDMs along with the rating costs for 
14 basic models. Market research tools report that company's annual 
revenue to be approximately $50.6 million. Accordingly, testing and 
AEDM costs to rate in accordance with appendix A1 could cause this 
small business manufacturer to incur costs significantly less than one 
percent of annual revenue for that small manufacturer.
3. Significant Alternatives to the Rule
    DOE considered alternative test methods and modifications to the 
adopted test procedures in appendices A and A1 for CUACs and CUHPs, 
referencing AHRI 340/360-2022 and AHRI 1340-2023, respectively. 
However, DOE has determined that there are no better alternatives than 
the adopted test procedures, in terms of both meeting the agency's 
objectives and reducing burden on manufacturers. Therefore, DOE is 
amending the existing DOE test procedure for CUACs and CUHPs through 
incorporation by reference of AHRI 340/360-2022 in appendix A, and 
incorporation by reference of AHRI 1340-2023 in appendix A1.
    As discussed previously, manufacturers, including small businesses, 
will have the option to implement AEDMs to certify their basic models--
which will likely be more cost-effective than testing each basic model. 
This option is explained in further detail in section III.K.2 of this 
document.
    In addition, individual manufacturers may petition for a waiver of 
the applicable test procedure. (See 10 CFR 431.401) Also, section 504 
of the Department of Energy Organization Act, 42 U.S.C. 7194, provides 
authority for the Secretary to adjust a rule issued under EPCA in order 
to prevent ``special hardship, inequity, or unfair distribution of 
burdens'' that may be imposed on that manufacturer as a result of such 
rule. Manufacturers should refer to 10 CFR part 1003 for additional 
details.
4. Certification Statement
    DOE identified 13 OEMs affected by this final rule, two of which 
would be considered small businesses. Of these two small businesses, 
one is a member of AHRI, and DOE has determined that the AHRI member 
company will already be testing to the updated industry test standard 
(i.e., AHRI 1340-2023) in order to certify in the AHRI Directory. 
Consequently, DOE does not anticipate its amended test procedure will 
add to the testing burden for this AHRI member small business. Finally, 
DOE has determined that testing costs and burden will not increase 
substantially for the non-AHRI-member small business either. As 
discussed previously, the amendments to appendix A will result in zero 
costs to that small manufacturer. Further, the new appendix A1 will 
have no cost impact until and if amended energy conservation standards 
denominated in terms of the new metrics IVEC and IVHE are adopted. DOE 
has determined that if energy conservation standards are amended, the 
potential cost associated with this final rule is significantly less 
than one percent of revenue for the one non-AHRI-member small business. 
Thus, DOE concludes that this rulemaking does not significantly affect 
a substantial number of small entities.
    Based on the limited number of small entities affected and the de 
minimis cost impacts, DOE certifies that this final rule does not have 
a ``significant economic impact on a substantial number of small 
entities,'' and accordingly, the Department has determined that the 
preparation of a FRFA is not warranted. DOE will transmit a 
certification and supporting statement of factual basis to the Chief 
Counsel for Advocacy of the Small Business Administration for review 
under 5 U.S.C. 605(b).

C. Review Under the Paperwork Reduction Act of 1995

    Manufacturers of CUACs and CUHPs must certify to DOE that their 
equipment complies with any applicable energy conservation standards. 
To certify compliance, manufacturers must first obtain test data for 
their equipment according to the DOE test procedures, including any 
amendments adopted for those test procedures. DOE has established 
regulations for the certification and recordkeeping requirements for 
all covered consumer products and commercial equipment, including CUACs 
and CUHPs. (See generally 10 CFR part 429.) The collection-of-
information requirement for the certification and recordkeeping is 
subject to review and approval by OMB under the Paperwork Reduction Act 
(PRA). This requirement has been approved by OMB under OMB control 
number 1910-1400. Public reporting burden for the certification is 
estimated to average 35 hours per response, including the time for 
reviewing instructions, searching existing data sources, gathering and 
maintaining the data needed, and completing and reviewing the 
collection of information.
    DOE is not amending the certification or reporting requirements for 
CUACs and CUHPs in this final rule. Instead, DOE may consider proposals 
to amend the certification requirements and reporting for CUACs and 
CUHPs under a separate rulemaking regarding appliance and equipment 
certification. DOE will address changes to OMB Control Number 1910-1400 
at that time, as necessary.
    Notwithstanding any other provision of the law, no person is 
required to respond to, nor shall any person be subject to a penalty 
for failure to comply with, a collection of information subject to the 
requirements of the PRA, unless that collection of information displays 
a currently valid OMB Control Number.

[[Page 44031]]

D. Review Under the National Environmental Policy Act of 1969

    In this final rule, DOE adopts test procedure amendments that it 
expects will be used to develop and implement future energy 
conservation standards for CUACs and CUHPs. DOE has determined that 
this rule falls into a class of actions that are categorically excluded 
from review under the National Environmental Policy Act of 1969 (42 
U.S.C. 4321 et seq.) and DOE's implementing regulations at 10 CFR part 
1021. Specifically, DOE has determined that adopting test procedures 
for measuring energy efficiency of consumer products and industrial 
equipment is consistent with activities identified in 10 CFR part 1021, 
subpart D, appendix A, sections A5 and A6. Accordingly, neither an 
environmental assessment nor an environmental impact statement is 
required.

E. Review Under Executive Order 13132

    Executive Order 13132, ``Federalism,'' 64 FR 43255 (August 4, 
1999), imposes certain requirements on agencies formulating and 
implementing policies or regulations that preempt State law or that 
have federalism implications. The Executive order requires agencies to 
examine the constitutional and statutory authority supporting any 
action that would limit the policymaking discretion of the States and 
to carefully assess the necessity for such actions. The Executive order 
also requires agencies to have an accountable process to ensure 
meaningful and timely input by State and local officials in the 
development of regulatory policies that have federalism implications. 
On March 14, 2000, DOE published a statement of policy describing the 
intergovernmental consultation process it will follow in the 
development of such regulations. 65 FR 13735. DOE examined this final 
rule and determined that it will not have a substantial direct effect 
on the States, on the relationship between the national government and 
the States, or on the distribution of power and responsibilities among 
the various levels of government. EPCA governs and prescribes Federal 
preemption of State regulations as to energy conservation for the 
products that are the subject of this final rule. States can petition 
DOE for exemption from such preemption to the extent, and based on 
criteria, set forth in EPCA. (42 U.S.C. 6297(d)) No further action is 
required by Executive Order 13132.

F. Review Under Executive Order 12988

    Regarding the review of existing regulations and the promulgation 
of new regulations, section 3(a) of Executive Order 12988, ``Civil 
Justice Reform,'' 61 FR 4729 (Feb. 7, 1996), imposes on Federal 
agencies the general duty to adhere to the following requirements: (1) 
eliminate drafting errors and ambiguity; (2) write regulations to 
minimize litigation; (3) provide a clear legal standard for affected 
conduct rather than a general standard; and (4) promote simplification 
and burden reduction. Regarding the review required by section 3(a), 
section 3(b) of Executive Order 12988 specifically requires that 
Executive agencies make every reasonable effort to ensure that the 
regulation: (1) clearly specifies the preemptive effect, if any; (2) 
clearly specifies any effect on existing Federal law or regulation; (3) 
provides a clear legal standard for affected conduct while promoting 
simplification and burden reduction; (4) specifies the retroactive 
effect, if any; (5) adequately defines key terms; and (6) addresses 
other important issues affecting clarity and general draftsmanship 
under any guidelines issued by the Attorney General. Section 3(c) of 
Executive Order 12988 sections 3(a) and 3(b) to determine whether they 
are met or it is unreasonable to meet one or more of them. DOE has 
completed the required review and determined that, to the extent 
permitted by law, this final rule meets the relevant standards of 
Executive Order 12988.

G. Review Under the Unfunded Mandates Reform Act of 1995

    Title II of the Unfunded Mandates Reform Act of 1995 (``UMRA'') 
requires each Federal agency to assess the effects of Federal 
regulatory actions on State, local, and Tribal governments and the 
private sector. Public Law 104-4, sec. 201 (codified at 2 U.S.C. 1531). 
For a regulatory action likely to result in a rule that may cause the 
expenditure by State, local, and Tribal governments, in the aggregate, 
or by the private sector of $100 million or more in any one year 
(adjusted annually for inflation), section 202 of UMRA requires a 
Federal agency to publish a written statement that estimates the 
resulting costs, benefits, and other effects on the national economy. 
(2 U.S.C. 1532(a), (b)) The UMRA also requires a Federal agency to 
develop an effective process to permit timely input by elected officers 
of State, local, and Tribal governments on a ``significant 
intergovernmental mandate,'' and requires an agency plan for giving 
notice and opportunity for timely input to potentially affected small 
governments before establishing any requirements that might 
significantly or uniquely affect them. On March 18, 1997, DOE published 
a statement of policy on its process for intergovernmental consultation 
under UMRA. 62 FR 12820. DOE's policy statement is also available at 
www.energy.gov/sites/prod/files/gcprod/documents/umra_97.pdf. DOE 
examined this final rule according to UMRA and its statement of policy 
and determined that the rule contains neither an intergovernmental 
mandate, nor a mandate that may result in the expenditure of $100 
million or more in any year, so these requirements do not apply.

H. Review Under the Treasury and General Government Appropriations Act, 
1999

    Section 654 of the Treasury and General Government Appropriations 
Act, 1999 (Pub. L. 105-277) requires Federal agencies to issue a Family 
Policymaking Assessment for any rule that may affect family well-being. 
This final rule will not have any impact on the autonomy or integrity 
of the family as an institution. Accordingly, DOE has concluded that it 
is not necessary to prepare a Family Policymaking Assessment.

I. Review Under Executive Order 12630

    DOE has determined, under Executive Order 12630, ``Governmental 
Actions and Interference with Constitutionally Protected Property 
Rights,'' 53 FR 8859 (March 18, 1988), that this regulation will not 
result in any takings that might require compensation under the Fifth 
Amendment to the U.S. Constitution.

J. Review Under Treasury and General Government Appropriations Act, 
2001

    Section 515 of the Treasury and General Government Appropriations 
Act, 2001 (44 U.S.C. 3516 note) provides for agencies to review most 
disseminations of information to the public under guidelines 
established by each agency pursuant to general guidelines issued by 
OMB. OMB's guidelines were published at 67 FR 8452 (Feb. 22, 2002), and 
DOE's guidelines were published at 67 FR 62446 (Oct. 7, 2002). Pursuant 
to OMB Memorandum M-19-15, Improving Implementation of the Information 
Quality Act (April 24, 2019), DOE published updated guidelines which 
are available at: www.energy.gov/sites/prod/files/2019/12/f70/DOE%20Final%20Updated%20IQA%20Guidelines%20Dec%202019.pdf. DOE has 
reviewed this final rule under the OMB and DOE guidelines and has 
concluded that it is consistent with applicable policies in those 
guidelines.

[[Page 44032]]

K. Review Under Executive Order 13211

    Executive Order 13211, ``Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use,'' 66 FR 28355 
(May 22, 2001), requires Federal agencies to prepare and submit to OIRA 
at OMB, a Statement of Energy Effects for any significant energy 
action. A ``significant energy action'' is defined as any action by an 
agency that promulgates or is expected to lead to promulgation of a 
final rule, and that: (1) is a significant regulatory action under 
Executive Order 12866, or any successor order, and (2) is likely to 
have a significant adverse effect on the supply, distribution, or use 
of energy, or (3) is designated by the Administrator of OIRA as a 
significant energy action. For any significant energy action, the 
agency must give a detailed statement of any adverse effects on energy 
supply, distribution, or use if the regulation is implemented, and of 
reasonable alternatives to the action and their expected benefits on 
energy supply, distribution, and use.
    This regulatory action to amend the test procedure for measuring 
the energy efficiency of CUACs and CUHPs is not a significant 
regulatory action under Executive Order 12866. Moreover, it would not 
have a significant adverse effect on the supply, distribution, or use 
of energy, nor has it been designated as a significant energy action by 
the Administrator of OIRA. Therefore, it is not a significant energy 
action, and, accordingly, DOE has not prepared a Statement of Energy 
Effects.

L. Review Under Section 32 of the Federal Energy Administration Act of 
1974

    Under section 301 of the Department of Energy Organization Act 
(Pub. L. 95-91; 42 U.S.C. 7101), DOE must comply with section 32 of the 
Federal Energy Administration Act of 1974, as amended by the Federal 
Energy Administration Authorization Act of 1977. (15 U.S.C. 788; 
``FEAA'') Section 32 essentially provides in relevant part that, where 
a proposed rule authorizes or requires use of commercial standards, the 
notice of proposed rulemaking must inform the public of the use and 
background of such standards. In addition, section 32(c) requires DOE 
to consult with the Attorney General and the Chairman of the Federal 
Trade Commission (``FTC'') concerning the impact of the commercial or 
industry standards on competition.
    The modifications to the test procedure for CUACs and CUHPs adopted 
in this final rule incorporate testing methods contained in certain 
sections of the following commercial standards: AHRI 340/360-2022, AHRI 
1340-2023, and ANSI/ASHRAE 37-2009. DOE has evaluated these standards 
and is unable to conclude whether they fully comply with the 
requirements of section 32(b) of the FEAA (i.e., whether they were 
developed in a manner that fully provides for public participation, 
comment, and review). DOE has consulted with both the Attorney General 
and the Chairman of the FTC about the impact on competition of using 
the methods contained in these standards and has received no comments 
objecting to their use.

M. Congressional Notification

    As required by 5 U.S.C. 801, DOE will report to Congress on the 
promulgation of this rule before its effective date. The report will 
state that the Office of Information and Regulatory Affairs has 
determined that this action is not a ``major rule'' under the criteria 
set forth in 5 U.S.C. 804(2).

N. Description of Materials Incorporated by Reference

    In this final rule, DOE is incorporating by reference the following 
test standards:
    AHRI 340/360-2022 is an industry-accepted test procedure for 
measuring the performance of air-cooled, evaporatively-cooled, and 
water-cooled unitary air-conditioning and heat pump equipment. AHRI 
340/360-2022 is available from AHRI at www.ahrinet.org/standards/search-standards.
    AHRI 1340-2023 is the most recent industry-accepted test procedure 
for measuring the performance of air-cooled, evaporatively-cooled, and 
water-cooled unitary air-conditioning and heat pump equipment. AHRI 
1340-2023 is available from AHRI at www.ahrinet.org/standards/search-standards.
    ANSI/ASHRAE 37-2009 is an industry-accepted test procedure for 
measuring the performance of electrically driven unitary air-
conditioning and heat pump equipment. ANSI/ASHRAE 37-2009 is available 
from ASHRAE on ANSI's website at: https://webstore.ansi.org/standards/ashrae/ansiashraestandard372009.

V. Approval of the Office of the Secretary

    The Secretary of Energy has approved publication of this final 
rule.

List of Subjects

10 CFR Part 429

    Administrative practice and procedure, Confidential business 
information, Energy conservation, Household appliances, Imports, 
Incorporation by reference, Intergovernmental relations, Reporting and 
recordkeeping requirements, Small businesses.

10 CFR Part 431

    Administrative practice and procedure, Confidential business 
information, Energy conservation test procedures, Incorporation by 
reference, Reporting and recordkeeping requirements.

Signing Authority

    This document of the Department of Energy was signed on April 12, 
2024, by Jeffrey Marootian, Principal Deputy Assistant Secretary for 
Energy Efficiency and Renewable Energy, pursuant to delegated authority 
from the Secretary of Energy. That document with the original signature 
and date is maintained by DOE. For administrative purposes only, and in 
compliance with requirements of the Office of the Federal Register, the 
undersigned DOE Federal Register Liaison Officer has been authorized to 
sign and submit the document in electronic format for publication, as 
an official document of the Department of Energy. This administrative 
process in no way alters the legal effect of this document upon 
publication in the Federal Register.

    Signed in Washington, DC, on April 17, 2024.
Treena V. Garrett,
Federal Register Liaison Officer, U.S. Department of Energy.

    For the reasons stated in the preamble, DOE amends parts 429 and 
431 of chapter II of title 10, Code of Federal Regulations as set forth 
below:

PART 429--CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER 
PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT

0
1. The authority citation for part 429 continues to read as follows:

    Authority: 42 U.S.C. 6291-6317; 28 U.S.C. 2461 note.

0
2. Amend Sec.  429.4 by:
0
a. Removing paragraph (c)(2);
0
b. Redesignating paragraphs (c)(3) through (5) as paragraphs (c)(2) 
through (4); and
0
c. Adding new paragraph (c)(5).
    The addition reads as follows:


Sec.  429.4  Materials incorporated by reference.

* * * * *
    (c) * * *
    (5) AHRI Standard 1340-2023 (I-P) (``AHRI 1340-2023''), 2023 
Standard for

[[Page 44033]]

Performance Rating of Commercial and Industrial Unitary Air-
conditioning and Heat Pump Equipment, approved November 16, 2023; IBR 
approved for Sec. Sec.  429.43; 429.134.
* * * * *

0
3. Amend Sec.  429.43 by:
0
a. Removing paragraph (a)(1)(iv);
0
b. Removing and reserving paragraph (a)(2)(ii); and
0
c. Adding paragraph (a)(3)(vi).
    The addition reads as follows:


Sec.  429.43  Commercial heating, ventilating, air conditioning (HVAC) 
equipment (excluding air-cooled, three-phase, small commercial package 
air conditioning and heating equipment with a cooling capacity of less 
than 65,000 British thermal units per hour and air-cooled, three-phase, 
variable refrigerant flow multi-split air conditioners and heat pumps 
with less than 65,000 British thermal units per hour cooling capacity).

    (a) * * *
    (3) * * *
    (vi) Commercial package air conditioning and heating equipment 
(excluding air-cooled equipment with a cooling capacity less than 
65,000 Btu/h). Before May 15, 2025, the provisions in 10 CFR 429.43, 
revised as of January 1, 2024, are applicable. On and after May 15, 
2025, when certifying to energy conservation standards in terms of EER 
or IEER and (as applicable) COP, the provisions in paragraph 
(a)(3)(vi)(B) of this section apply. When certifying to energy 
conservation standards in terms of IVEC and (as applicable) IVHE, all 
provisions in this paragraph (a)(3)(vi) apply.
    (A) For individual model selection when certifying to energy 
conservation standards in terms of IVEC and (as applicable) IVHE:
    (1) Representations for a basic model must be based on the least-
efficient individual model(s) distributed in commerce among all 
otherwise comparable model groups comprising the basic model, with 
selection of the least-efficient individual model considering all 
options for factory-installed components and manufacturer-supplied 
components for field installation, except as provided in paragraph 
(a)(3)(vi)(A)(2) of this section for individual models that include 
components listed in table 7 to paragraph (a)(3)(vi)(A) of this 
section. For the purpose of this paragraph (a)(3)(vi)(A)(1), 
``otherwise comparable model group'' means a group of individual models 
distributed in commerce within the basic model that do not differ in 
components that affect energy consumption as measured according to the 
applicable test procedure specified at 10 CFR 431.96 other than those 
listed in table 7 to paragraph (a)(3)(vi)(A) of this section. An 
otherwise comparable model group may include individual models 
distributed in commerce with any combination of the components listed 
in table 7 (or none of the components listed in table 7). An otherwise 
comparable model group may consist of only one individual model.
    (2) For a basic model that includes individual models distributed 
in commerce with components listed in table 7 to paragraph 
(a)(3)(vi)(A) of this section, the requirements for determining 
representations apply only to the individual model(s) of a specific 
otherwise comparable model group distributed in commerce with the least 
number (which could be zero) of components listed in table 7 to 
paragraph (a)(3)(vi)(A) included in individual models of the group. 
Testing under this paragraph (a)(3)(vi)(A)(2) shall be consistent with 
any component-specific test provisions specified in section 6 of 
appendix A1 to subpart F of 10 CFR part 431.

   Table 7 to Paragraph (a)(3)(vi)(A)--Specific Components for Commercial Package Air Conditioning and Heating
                                                    Equipment
               [Excluding air-cooled equipment with a cooling capacity of less than 65,000 Btu/h]
----------------------------------------------------------------------------------------------------------------
                  Component                                               Description
----------------------------------------------------------------------------------------------------------------
Air Economizers.............................  An automatic system that enables a cooling system to supply
                                               outdoor air to reduce or eliminate the need for mechanical
                                               cooling during mild or cold weather.
Desiccant Dehumidification Components.......  An assembly that reduces the moisture content of the supply air
                                               through moisture transfer with solid or liquid desiccants.
Evaporative Pre-cooling of Air-cooled         Water is evaporated into the air entering the air-cooled condenser
 Condenser Intake Air.                         to lower the dry-bulb temperature and thereby increase efficiency
                                               of the refrigeration cycle.
Fire/Smoke/Isolation Dampers................  A damper assembly including means to open and close the damper
                                               mounted at the supply or return duct opening of the equipment.
Indirect/Direct Evaporative Cooling of        Water is used indirectly or directly to cool ventilation air. In a
 Ventilation Air.                              direct system, the water is introduced directly into the
                                               ventilation air, and in an indirect system, the water is
                                               evaporated in secondary air stream, and the heat is removed
                                               through a heat exchanger.
Non-Standard Ducted Condenser Fans (not       A higher-static condenser fan/motor assembly designed for external
 applicable to Double-duct Systems).           ducting of condenser air that provides greater pressure rise and
                                               has a higher rated motor horsepower than the condenser fan
                                               provided as a standard component with the equipment.
Non-Standard High-Static Indoor Fan Motors..  The standard indoor fan motor is the motor specified in the
                                               manufacturer's installation instructions for testing and shall be
                                               distributed in commerce as part of a particular model. A non-
                                               standard motor is an indoor fan motor that is not the standard
                                               indoor fan motor and that is distributed in commerce as part of
                                               an individual model within the same basic model.
                                              For a non-standard high-static indoor fan motor(s) to be
                                               considered a specific component for a basic model (and thus
                                               subject to the provisions of paragraph (a)(3)(vi)(A)(2) of this
                                               section), the following provisions must be met:
                                                 (1) Non-standard high-static indoor fan motor(s) must meet the
                                                  minimum allowable efficiency determined per section D.3.1 of
                                                  AHRI 1340-2023 (incorporated by reference, see Sec.   429.4)
                                                  for non-standard high-static indoor fan motors or per section
                                                  D.3.2 of AHRI 1340-2023 for non-standard high-static indoor
                                                  integrated fan and motor combinations.
                                                 (2) If the standard indoor fan motor can vary fan speed through
                                                  control system adjustment of motor speed, all non-standard
                                                  high-static indoor fan motors must also allow speed control
                                                  (including with the use of variable-frequency drive).
Powered Exhaust/Powered Return Air Fans.....  A powered exhaust fan is a fan that transfers directly to the
                                               outside a portion of the building air that is returning to the
                                               unit, rather than allowing it to recirculate to the indoor coil
                                               and back to the building. A powered return fan is a fan that
                                               draws building air into the equipment.

[[Page 44034]]

 
Process Heat recovery/Reclaim Coils/Thermal   A heat exchanger located inside the unit that conditions the
 Storage.                                      equipment's supply air using energy transferred from an external
                                               source using a vapor, gas, or liquid.
Refrigerant Reheat Coils....................  A heat exchanger located downstream of the indoor coil that heats
                                               the supply air during cooling operation using high pressure
                                               refrigerant in order to increase the ratio of moisture removal to
                                               cooling capacity provided by the equipment.
Sound Traps/Sound Attenuators...............  An assembly of structures through which the supply air passes
                                               before leaving the equipment or through which the return air from
                                               the building passes immediately after entering the equipment for
                                               which the sound insertion loss is at least 6 dB for the 125 Hz
                                               octave band frequency range.
Steam/Hydronic Heat Coils...................  Coils used to provide supplemental heating.
Ventilation Energy Recovery System (VERS)...  An assembly that preconditions outdoor air entering the equipment
                                               through direct or indirect thermal and/or moisture exchange with
                                               the exhaust air, which is defined as the building air being
                                               exhausted to the outside from the equipment.
----------------------------------------------------------------------------------------------------------------

    (B) The represented value of total cooling capacity must be between 
95 percent and 100 percent of the mean of the total cooling capacities 
measured for the units in the sample selected as described in paragraph 
(a)(1)(ii) of this section, or between 95 percent and 100 percent of 
the total cooling capacity output simulated by the AEDM as described in 
paragraph (a)(2) of this section.
    (C) Representations of IVEC and IVHE (including IVHEc, 
as applicable) must be determined using a minimum part-load airflow 
that is no lower than the highest of the following:
    (1) The minimum part-load airflow obtained using the as-shipped 
system control settings;
    (2) The minimum part-load airflow obtained using the default system 
control settings specified in the manufacturer installation 
instructions (as applicable); and
    (3) The minimum airflow rate specified in section 5.18.2 of AHRI 
1340-2023.
* * * * *

0
4. Amend Sec.  429.70 by revising table 2 to paragraph (c)(5)(vi)(B) to 
read as follows:


Sec.  429.70  Alternative methods for determining energy efficiency and 
energy use.

* * * * *
    (c) * * *
    (5) * * *
    (vi) * * *
    (B) * * *

                   Table 2 to Paragraph (c)(5)(vi)(B)
------------------------------------------------------------------------
                                                            Applicable
           Equipment                      Metric             tolerance
------------------------------------------------------------------------
Commercial Packaged Boilers....  Combustion Efficiency..       5% (0.05)
                                 Thermal Efficiency.....       5% (0.05)
Commercial Water Heaters or Hot  Thermal Efficiency.....       5% (0.05)
 Water Supply Boilers.
                                 Standby Loss...........       10% (0.1)
Unfired Storage Tanks..........  R-Value................       10% (0.1)
Air-Cooled, Split and Packaged   Energy Efficiency Ratio       5% (0.05)
 ACs and HPs Greater Than or     Energy Efficiency Ratio       5% (0.05)
 Equal to 65,000 Btu/h Cooling    2.                           5% (0.05)
 Capacity and Less than 760,000  Coefficient of                5% (0.05)
 Btu/h Cooling Capacity.          Performance.                 10% (0.1)
                                 Coefficient of                10% (0.1)
                                  Performance 2.               10% (0.1)
                                 Integrated Energy
                                  Efficiency Ratio.
                                 Integrated Ventilation,
                                  Economizing, and
                                  Cooling.
                                 Integrated Ventilation
                                  and Heating Efficiency.
Water-Cooled, Split and          Energy Efficiency Ratio       5% (0.05)
 Packaged ACs, All Cooling       Energy Efficiency Ratio       5% (0.05)
 Capacities.                      2.                           10% (0.1)
                                 Integrated Energy             10% (0.1)
                                  Efficiency Ratio.
                                 Integrated Ventilation,
                                  Economizing, and
                                  Cooling.
Evaporatively-Cooled, Split and  Energy Efficiency Ratio       5% (0.05)
 Packaged ACs, All Capacities.   Energy Efficiency Ratio       5% (0.05)
                                  2.                           10% (0.1)
                                 Integrated Energy             10% (0.1)
                                  Efficiency Ratio.
                                 Integrated Ventilation,
                                  Economizing, and
                                  Cooling.
Water-Source HPs, All            Energy Efficiency Ratio       5% (0.05)
 Capacities.
                                 Coefficient of                5% (0.05)
                                  Performance.
                                 Integrated Energy             10% (0.1)
                                  Efficiency Ratio.
Single Package Vertical ACs and  Energy Efficiency Ratio       5% (0.05)
 HPs.
                                 Coefficient of                5% (0.05)
                                  Performance.
Packaged Terminal ACs and HPs..  Energy Efficiency Ratio       5% (0.05)
                                 Coefficient of                5% (0.05)
                                  Performance.
Variable Refrigerant Flow ACs    Energy Efficiency Ratio       5% (0.05)
 and HPs (Excluding Air-Cooled,  Coefficient of                5% (0.05)
 Three-phase with Less Than       Performance.                 10% (0.1)
 65,000 Btu/h Cooling Capacity). Integrated Energy
                                  Efficiency Ratio.
Computer Room Air Conditioners.  Sensible Coefficient of       5% (0.05)
                                  Performance.
Direct Expansion- Dedicated      Integrated Seasonal           10% (0.1)
 Outdoor Air Systems.             Coefficient of               10% (0.1)
                                  Performance 2.
                                 Integrated Seasonal
                                  Moisture Removal
                                  Efficiency 2.

[[Page 44035]]

 
Commercial Warm-Air Furnaces...  Thermal Efficiency.....       5% (0.05)
Commercial Refrigeration         Daily Energy                  5% (0.05)
 Equipment.                       Consumption.
------------------------------------------------------------------------

* * * * *

0
5. Amend Sec.  429.134 by revising paragraph (g) to read as follows:


Sec.  429.134  Product-specific enforcement provisions.

* * * * *
    (g) Commercial package air conditioning and heating equipment 
(excluding air-cooled equipment with a cooling capacity less than 
65,000 Btu/h). Before May 15, 2025, the provisions in 10 CFR 429.134, 
revised as of January 1, 2024, are applicable. On and after May 15, 
2025, the following provisions apply.
    (1) Verification of cooling capacity. The cooling capacity of each 
tested unit of the basic model will be measured pursuant to the test 
requirements of appendix A or appendix A1 to subpart F of part 431. The 
mean of the cooling capacity measurement(s) will be used to determine 
the applicable standards for purposes of compliance.
    (2) Specific components. For assessment and enforcement testing of 
models subject to energy conservation standards denominated in terms of 
IVEC and IVHE, if a basic model includes individual models with 
components listed at table 7 to Sec.  429.43(a)(3)(vi)(A) and DOE is 
not able to obtain an individual model with the least number (which 
could be zero) of those components within an otherwise comparable model 
group (as defined in Sec.  429.43(a)(3)(vi)(A)(1)), DOE may test any 
individual model within the otherwise comparable model group.
    (3) Verification of cut-out and cut-in temperatures. For assessment 
and enforcement testing of models of commercial package air 
conditioning and heating equipment subject to energy conservation 
standards denominated in terms of IVHE, the cut-out and cut-in 
temperatures may be verified using the method in appendix H to AHRI 
1340-2023 (incorporated by reference, see Sec.  429.4). If this method 
is conducted, the cut-in and cut-out temperatures determined using this 
method will be used to calculate IVHE for purposes of compliance.
* * * * *

PART 431--ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND 
INDUSTRIAL EQUIPMENT

0
6. The authority citation for part 431 continues to read as follows:

    Authority: 42 U.S.C. 6291-6317; 28 U.S.C. 2461 note.


0
7. Amend Sec.  431.92 by:
0
a. Revising the definitions for ``Basic model'' and ``Coefficient of 
performance, or COP'';
0
b. Adding in alphabetical order a definition for ``Coefficient of 
performance 2, or COP2'';
0
c. Revising the definitions for ``Double-duct air conditioner or heat 
pump'' and ``Energy efficiency ratio, or EER'';
0
d. Adding in alphabetical order a definition for ``Energy efficiency 
ratio 2, or EER2'';
0
e. Revising the definition for ``Integrated energy efficiency ratio, or 
IEER''; and
0
f. Adding in alphabetical order definitions for ``Integrated 
ventilation and heating efficiency, or IVHE'' and ``Integrated 
ventilation, economizing, and cooling, or IVEC''.
    The revisions and additions read as follows:


Sec.  431.92   Definitions concerning commercial air conditioners and 
heat pumps.

* * * * *
    Basic model means:
    (1) For air-cooled, three-phase, small commercial package air 
conditioning and heating equipment with a cooling capacity of less than 
65,000 Btu/h and air-cooled, three-phase, variable refrigerant flow 
multi-split air conditioners and heat pumps with a cooling capacity of 
less than 65,000 Btu/h. All units manufactured by one manufacturer, 
having the same primary energy source, and, which have essentially 
identical electrical, physical, and functional (or hydraulic) 
characteristics that affect energy consumption, energy efficiency, 
water consumption, or water efficiency; where essentially identical 
electrical, physical, and functional (or hydraulic) characteristics 
means:
    (i) For split systems manufactured by outdoor unit manufacturers 
(OUMs): all individual combinations having the same model of outdoor 
unit, which means comparably performing compressor(s) [a variation of 
no more than five percent in displacement rate (volume per time) as 
rated by the compressor manufacturer, and no more than five percent in 
capacity and power input for the same operating conditions as rated by 
the compressor manufacturer], outdoor coil(s) [no more than five 
percent variation in face area and total fin surface area; same fin 
material; same tube material], and outdoor fan(s) [no more than ten 
percent variation in airflow and no more than twenty percent variation 
in power input];
    (ii) For split systems having indoor units manufactured by 
independent coil manufacturers (ICMs): all individual combinations 
having comparably performing indoor coil(s) [plus or minus one square 
foot face area, plus or minus one fin per inch fin density, and the 
same fin material, tube material, number of tube rows, tube pattern, 
and tube size]; and
    (iii) For single-package systems: all individual models having 
comparably performing compressor(s) [no more than five percent 
variation in displacement rate (volume per time) rated by the 
compressor manufacturer, and no more than five percent variations in 
capacity and power input rated by the compressor manufacturer 
corresponding to the same compressor rating conditions], outdoor 
coil(s) and indoor coil(s) [no more than five percent variation in face 
area and total fin surface area; same fin material; same tube 
material], outdoor fan(s) [no more than ten percent variation in 
outdoor airflow], and indoor blower(s) [no more than ten percent 
variation in indoor airflow, with no more than twenty percent variation 
in fan motor power input];
    (iv) Except that:
    (A) For single-package systems and single-split systems, 
manufacturers may instead choose to make each individual model/
combination its own basic model provided the testing and represented 
value requirements in 10 CFR 429.67 are met; and
    (B) For multi-split, multi-circuit, and multi-head mini-split 
combinations, a basic model may not include both

[[Page 44036]]

individual small-duct, high velocity (SDHV) combinations and non-SDHV 
combinations even when they include the same model of outdoor unit. The 
manufacturer may choose to identify specific individual combinations as 
additional basic models.
    (2) For commercial package air conditioning and heating equipment 
(excluding air-cooled, three-phase, commercial package air conditioning 
and heating equipment with a cooling capacity of less than 65,000 Btu/
h). All units manufactured by one manufacturer within a single 
equipment class, having the same or comparably performing 
compressor(s), heat exchangers, and air moving system(s) that have a 
common ``nominal'' cooling capacity.
    (3) For computer room air conditioners. All units manufactured by 
one manufacturer within a single equipment class, having the same 
primary energy source (e.g., electric or gas), and which have the same 
or comparably performing compressor(s), heat exchangers, and air moving 
system(s) that have a common ``nominal'' cooling capacity.
    (4) For direct expansion-dedicated outdoor air system. All units 
manufactured by one manufacturer, having the same primary energy source 
(e.g., electric or gas), within a single equipment class; with the same 
or comparably performing compressor(s), heat exchangers, ventilation 
energy recovery system(s) (if present), and air moving system(s) that 
have a common ``nominal'' moisture removal capacity.
    (5) For packaged terminal air conditioner (PTAC) or packaged 
terminal heat pump (PTHP). All units manufactured by one manufacturer 
within a single equipment class, having the same primary energy source 
(e.g., electric or gas), and which have the same or comparable 
compressors, same or comparable heat exchangers, and same or comparable 
air moving systems that have a cooling capacity within 300 Btu/h of one 
another.
    (6) For single package vertical units. All units manufactured by 
one manufacturer within a single equipment class, having the same 
primary energy source (e.g., electric or gas), and which have the same 
or comparably performing compressor(s), heat exchangers, and air moving 
system(s) that have a rated cooling capacity within 1500 Btu/h of one 
another.
    (7) For variable refrigerant flow systems (excluding air-cooled, 
three-phase, variable refrigerant flow air conditioners and heat pumps 
with a cooling capacity of less than 65,000 Btu/h). All units 
manufactured by one manufacturer within a single equipment class, 
having the same primary energy source (e.g., electric or gas), and 
which have the same or comparably performing compressor(s) that have a 
common ``nominal'' cooling capacity and the same heat rejection medium 
(e.g., air or water) (includes VRF water source heat pumps).
    (8) For water-source heat pumps. All units manufactured by one 
manufacturer within a single equipment class, having the same primary 
energy source (e.g., electric or gas), and which have the same or 
comparable compressors, same or comparable heat exchangers, and same or 
comparable ``nominal'' cooling capacity.
* * * * *
    Coefficient of performance, or COP, means the ratio of the produced 
cooling effect of an air conditioner or heat pump (or its produced 
heating effect, depending on the mode of operation) to its net work 
input, when both the cooling (or heating) effect and the net work input 
are expressed in identical units of measurement. For air-cooled 
commercial package air conditioning and heating equipment (excluding 
equipment with a cooling capacity less than 65,000 Btu/h), COP is 
measured per appendix A to this subpart.
    Coefficient of performance 2, or COP2, means the ratio of the 
produced cooling effect of an air conditioner or heat pump (or its 
produced heating effect, depending on the mode of operation) to its net 
work input, when both the cooling (or heating) effect and the net work 
input are expressed in identical units of measurement. COP2 must be 
used with a subscript to indicate the outdoor temperature in degrees 
Fahrenheit at which the COP2 was measured (e.g., COP217 for 
COP2 measured at 17 [deg]F). For air-cooled commercial package air 
conditioning and heating equipment (excluding equipment with a cooling 
capacity less than 65,000 Btu/h), COP2 is measured per appendix A1 to 
this subpart.
* * * * *
    Double-duct air conditioner or heat pump means air-cooled 
commercial package air conditioning and heating equipment that meets 
the following criteria--
    (1) Is either a horizontal single package or split-system unit; or 
a vertical unit that consists of two components that may be shipped or 
installed either connected or split; or a vertical single package unit 
that is not intended for exterior mounting on, adjacent interior to, or 
through an outside wall;
    (2) Is intended for indoor installation with ducting of outdoor air 
from the building exterior to and from the unit (e.g., the unit and/or 
all of its components are non-weatherized);
    (3) If it is a horizontal unit, the complete unit shall have a 
maximum height of 35 inches or the unit shall have components that do 
not exceed a maximum height of 35 inches. If it is a vertical unit, the 
complete (split, connected, or assembled) unit shall have components 
that do not exceed a maximum depth of 35 inches; and
    (4) Has a rated cooling capacity greater than or equal to 65,000 
Btu/h and less than 300,000 Btu/h.
* * * * *
    Energy efficiency ratio, or EER, means the ratio of the produced 
cooling effect of an air conditioner or heat pump to its net work 
input, expressed in Btu/watt-hour. For commercial package air 
conditioning and heating equipment (excluding air-cooled equipment with 
a cooling capacity less than 65,000 Btu/h), EER is measured per 
appendix A to this subpart.
    Energy efficiency ratio 2, or EER2, means the ratio of the produced 
cooling effect of an air conditioner or heat pump to its net work 
input, expressed in Btu/watt-hour. For commercial package air 
conditioning and heating equipment (excluding air-cooled equipment with 
a cooling capacity less than 65,000 Btu/h), EER2 is measured per 
appendix A1 to this subpart.
* * * * *
    Integrated energy efficiency ratio, or IEER, means a weighted 
average calculation of mechanical cooling EERs determined for four load 
levels and corresponding rating conditions, expressed in Btu/watt-hour. 
IEER is measured:
    (1) Per appendix A to this subpart for commercial package air 
conditioning and heating equipment (excluding air-cooled equipment with 
a cooling capacity less than 65,000 Btu/h);
    (2) Per appendix C1 to this subpart for water-source heat pumps;
    (3) Per appendix D1 to this subpart for variable refrigerant flow 
multi-split air conditioners and heat pumps (other than air-cooled with 
rated cooling capacity less than 65,000 Btu/h); and
    (4) Per appendix G1 to this subpart for single package vertical air 
conditioners and single package vertical heat pumps.
* * * * *
    Integrated ventilation and heating efficiency, or IVHE, means a sum 
of the space heating provided (Btu) divided by the sum of the energy 
consumed (Wh), including mechanical heating, supplementary electric 
resistance

[[Page 44037]]

heating, and heating season ventilation operating modes. IVHE with 
subscript C (IVHEC) refers to the IVHE of heat pumps using a 
cold-climate heating load line. For air-cooled commercial package air 
conditioning and heating equipment (excluding equipment with a cooling 
capacity less than 65,000 Btu/h), IVHE and IVHEC are 
measured per appendix A1 to this subpart.
    Integrated ventilation, economizing, and cooling, or IVEC, means a 
sum of the space cooling provided (Btu) divided by the sum of the 
energy consumed (Wh), including mechanical cooling, economizing, and 
cooling season ventilation operating modes. For commercial package air 
conditioning and heating equipment (excluding air-cooled equipment with 
a cooling capacity less than 65,000 Btu/h), IVEC is measured per 
appendix A1 to this subpart.
* * * * *

0
8. Amend Sec.  431.95 by:
0
a. Revising paragraph (b)(4);
0
b. Redesignating paragraph (b)(11) as paragraph (b)(12);
0
c. Adding new paragraph (b)(11); and
0
d. Revising paragraph (c)(2).
    The revision and addition read as follows:


Sec.  431.95  Materials incorporated by reference.

* * * * *
    (b) * * *
    (4) AHRI Standard 340/360-2022 (I-P) (``AHRI 340/360-2022''), 2022 
Standard for Performance Rating of Commercial and Industrial Unitary 
Air-conditioning and Heat Pump Equipment, approved January 26, 2022; 
IBR approved for appendix A to this subpart.
* * * * *
    (11) AHRI Standard 1340-2023 (I-P) (``AHRI 1340-2023''), 2023 
Standard for Performance Rating of Commercial and Industrial Unitary 
Air-conditioning and Heat Pump Equipment, approved November 16, 2023; 
IBR approved for appendix A1 to this subpart.
* * * * *
    (c) * * *
    (2) ANSI/ASHRAE Standard 37-2009 (``ANSI/ASHRAE 37-2009''), Methods 
of Testing for Rating Electrically Driven Unitary Air-Conditioning and 
Heat Pump Equipment, approved June 24, 2009; IBR approved for Sec.  
431.96 and appendices A, A1, B, C1, D1, E1, F1, G, and G1 to this 
subpart.
* * * * *

0
9. Amend Sec.  431.96 by revising table 1 to paragraph (b) to read as 
follows:


Sec.  431.96  Uniform test method for the measurement of energy 
efficiency of commercial air conditioners and heat pumps.

* * * * *
    (b) * * *

                                Table 1 to Paragraph (b)--Test Procedures for Commercial Air Conditioners and Heat Pumps
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                      Additional test
                                                              Cooling  capacity or                                Use tests,        procedure provisions
             Equipment                      Category            moisture  removal      Energy  efficiency       conditions, an      as indicated in the
                                                                  capacity \1\             descriptor           procedures in       listed paragraphs of
                                                                                                                                        this section
--------------------------------------------------------------------------------------------------------------------------------------------------------
Commercial Package Air Conditioning  Air-Cooled, 3-Phase,    <65,000 Btu/h.........  SEER and HSPF........  Appendix F to this     None.
 and Heating Equipment.               AC and HP.                                                             subpart \2\.
Commercial Package Air Conditioning  Air-Cooled, 3-Phase,    <65,000 Btu/h.........  SEER2 and HSPF2......  Appendix F1 to this    None.
 and Heating Equipment.               AC and HP.                                                             subpart \2\.
Commercial Package Air Conditioning  Air-Cooled AC and HP    >=65,000 Btu/h and      EER, IEER, and COP...  Appendix A to this     None.
 and Heating Equipment.               (excluding double-      <760,000 Btu/h.                                subpart \2\.
                                      duct AC and HP).
Commercial Package Air Conditioning  Air-Cooled AC and HP    >=65,000 Btu/h and      EER2, COP2, IVEC, and  Appendix A1 to this    None.
 and Heating Equipment.               (excluding double-      <760,000 Btu/h.         IVHE.                  subpart \2\.
                                      duct AC and HP).
Commercial Package Air Conditioning  Double-duct AC and HP.  >=65,000 Btu/h and      EER, IEER, and COP...  Appendix A to this     None.
 and Heating Equipment.                                       <300,000 Btu/h.                                subpart \2\.
Commercial Package Air Conditioning  Double-duct AC and HP.  >=65,000 Btu/h and      EER2, COP2, IVEC, and  Appendix A1 to this    None.
 and Heating Equipment.                                       <300,000 Btu/h.         IVHE.                  subpart \2\.
Commercial Package Air Conditioning  Water-Cooled and        <760,000 Btu/h........  EER and IEER.........  Appendix A to this     None.
 and Heating Equipment.               Evaporatively-Cooled                                                   subpart \2\.
                                      AC.
Commercial Package Air Conditioning  Water-Cooled and        <760,000 Btu/h........  EER2 and IVEC........  Appendix A1 to this    None.
 and Heating Equipment.               Evaporatively-Cooled                                                   subpart \2\.
                                      AC.
Water-Source Heat Pumps............  HP....................  <760,000 Btu/h........  EER and COP..........  Appendix C to this     None.
                                                                                                             subpart \2\.
Water-Source Heat Pumps............  HP....................  <760,000 Btu/h........  IEER and ACOP........  Appendix C1 to this    None.
                                                                                                             subpart \2\.
Packaged Terminal Air Conditioners   AC and HP.............  <760,000 Btu/h........  EER and COP..........  Paragraph (g) of this  Paragraphs (c), (e),
 and Heat Pumps.                                                                                             section.               and (g).
Computer Room Air Conditioners.....  AC....................  <760,000 Btu/h........  SCOP.................  Appendix E to this     None.
                                                                                                             subpart \2\.
Computer Room Air Conditioners.....  AC....................  <760,000 Btu/h or       NSenCOP..............  Appendix E1 to this    None.
                                                              <930,000 Btu/h \3\.                            subpart \2\.
Variable Refrigerant Flow Multi-     AC....................  <65,000 Btu/h (3-       SEER.................  Appendix F to this     None.
 split Systems.                                               phase).                                        subpart \2\.
Variable Refrigerant Flow Multi-     AC....................  <65,000 Btu/h (3-       SEER2................  Appendix F1 to this    None.
 split Systems.                                               phase).                                        subpart \2\.
Variable Refrigerant Flow Multi-     HP....................  <65,000 Btu/h (3-       SEER and HSPF........  Appendix F to this     None.
 split Systems, Air-cooled.                                   phase).                                        subpart \2\.
Variable Refrigerant Flow Multi-     HP....................  <65,000 Btu/h (3-       SEER2 and HSPF2......  Appendix F1 to this    None.
 split Systems, Air-cooled.                                   phase).                                        subpart \2\.

[[Page 44038]]

 
Variable Refrigerant Flow Multi-     AC and HP.............  >=65,000 Btu/h and      EER and COP..........  Appendix D to this     None.
 split Systems, Air-cooled.                                   <760,000 Btu/h.                                subpart \2\.
Variable Refrigerant Flow Multi-     AC and HP.............  >=65,000 Btu/h and      IEER and COP.........  Appendix D1 to this    None.
 split Systems, Air-cooled.                                   <760,000 Btu/h.                                subpart \2\.
Variable Refrigerant Flow Multi-     HP....................  <760,000 Btu/h........  EER and COP..........  Appendix D to this     None.
 split Systems, Water-source.                                                                                subpart \2\.
Variable Refrigerant Flow Multi-     HP....................  <760,000 Btu/h........  IEER and COP.........  Appendix D1 to this    None.
 split Systems, Water-source.                                                                                subpart \2\.
Single Package Vertical Air          AC and HP.............  <760,000 Btu/h........  EER and COP..........  Appendix G to this     None.
 Conditioners and Single Package                                                                             subpart \2\.
 Vertical Heat Pumps.
Single Package Vertical Air          AC and HP.............  <760,000 Btu/h........  EER, IEER, and COP...  Appendix G1 to this    None.
 Conditioners and Single Package                                                                             subpart \2\.
 Vertical Heat Pumps.
Direct Expansion-Dedicated Outdoor   All...................  <324 lbs. of moisture   ISMRE2 and ISCOP2....  Appendix B to this     None.
 Air Systems.                                                 removal/hr.                                    subpart.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Moisture removal capacity applies only to direct expansion-dedicated outdoor air systems.
\2\ For equipment with multiple appendices listed in this table, consult the notes at the beginning of those appendices to determine the applicable
  appendix to use for testing.
\3\ For upflow ducted and downflow floor-mounted computer room air conditioners, the test procedure in appendix E1 to this subpart applies to equipment
  with net sensible cooling capacity less than 930,000 Btu/h. For all other configurations of computer room air conditioners, the test procedure in
  appendix E1 to this subpart applies to equipment with net sensible cooling capacity less than 760,000 Btu/h.

* * * * *

0
10. Revise Sec.  431.97 to read as follows:


Sec.  431.97  Energy efficiency standards and their compliance dates.

    (a) All basic models of commercial package air conditioning and 
heating equipment must be tested for performance using the applicable 
DOE test procedure in Sec.  431.96, be compliant with the applicable 
standards set forth in paragraphs (b) through (i) of this section, and 
be certified to the Department under 10 CFR part 429.
    (b) Each commercial package air conditioning and heating equipment 
(excluding air-cooled equipment with cooling capacity less than 65,000 
Btu/h) manufactured starting on the compliance date listed in tables 1 
through 4 to this paragraph (b) must meet the applicable minimum energy 
efficiency standard level(s) set forth in tables 1 through 4.

  Table 1 to Paragraph (b)--Minimum Efficiency Standards for Air-Cooled Commercial Package Air Conditioning and
                 Heating Equipment With a Cooling Capacity Greater Than or Equal to 65,000 Btu/h
                             [Excluding double-duct air-conditioners and heat pumps]
----------------------------------------------------------------------------------------------------------------
                                                                                              Compliance date:
                                                    Supplementary     Minimum efficiency         equipment
       Cooling capacity            Subcategory      heating type             \1\           manufactured starting
                                                                                                  on . . .
----------------------------------------------------------------------------------------------------------------
  Air-Cooled Commercial Package Air Conditioning and Heating Equipment with a Cooling Capacity Greater Than or
                  Equal to 65,000 Btu/h (Excluding Double-Duct Air Conditioners and Heat Pumps)
----------------------------------------------------------------------------------------------------------------
>=65,000 Btu/h and <135,000     AC..............  Electric          IEER = 14.8..........  January 1, 2023.
 Btu/h.                                            Resistance
                                                   Heating or No
                                                   Heating.
>=65,000 Btu/h and <135,000     AC..............  All Other Types   IEER = 14.6..........  January 1, 2023.
 Btu/h.                                            of Heating.
>=65,000 Btu/h and <135,000     HP..............  Electric          IEER = 14.1..........  January 1, 2023.
 Btu/h.                                            Resistance       COP = 3.4............
                                                   Heating or No
                                                   Heating.
>=65,000 Btu/h and <135,000     HP..............  All Other Types   IEER = 13.9..........  January 1, 2023.
 Btu/h.                                            of Heating.      COP = 3.4............
>=135,000 Btu/h and <240,000    AC..............  Electric          IEER = 14.2..........  January 1, 2023.
 Btu/h.                                            Resistance
                                                   Heating or No
                                                   Heating.
>=135,000 Btu/h and <240,000    AC..............  All Other Types   IEER = 14.0..........  January 1, 2023.
 Btu/h.                                            of Heating.
>=135,000 Btu/h and <240,000    HP..............  Electric          IEER = 13.5..........  January 1, 2023.
 Btu/h.                                            Resistance       COP = 3.3............
                                                   Heating or No
                                                   Heating.
>=135,000 Btu/h and <240,000    HP..............  All Other Types   IEER = 13.3..........  January 1, 2023.
 Btu/h.                                            of Heating.      COP = 3.3............
>=240,000 Btu/h and <760,000    AC..............  Electric          IEER = 13.2..........  January 1, 2023.
 Btu/h.                                            Resistance
                                                   Heating or No
                                                   Heating.
>=240,000 Btu/h and <760,000    AC..............  All Other Types   IEER = 13.0..........  January 1, 2023.
 Btu/h.                                            of Heating.
>=240,000 Btu/h and <760,000    HP..............  Electric          IEER = 12.5..........  January 1, 2023.
 Btu/h.                                            Resistance       COP = 3.2............
                                                   Heating or No
                                                   Heating.
>=240,000 Btu/h and <760,000    HP..............  All Other Types   IEER = 12.3..........  January 1, 2023.
 Btu/h.                                            of Heating.      COP = 3.2............
----------------------------------------------------------------------------------------------------------------
\1\ See section 3 of appendix A to this subpart for the test conditions upon which the COP standards are based.


[[Page 44039]]


     Table 2 to Paragraph (b)--Minimum Cooling Efficiency Standards for Water-Cooled Commercial Package Air
                                             Conditioning Equipment
----------------------------------------------------------------------------------------------------------------
                                                                                             Compliance date:
           Cooling capacity             Supplementary heating      Minimum efficiency     equipment manufactured
                                                 type                                       starting on . . .
----------------------------------------------------------------------------------------------------------------
                           Water-Cooled Commercial Package Air Conditioning Equipment
----------------------------------------------------------------------------------------------------------------
<65,000 Btu/h........................  All....................  EER = 12.1.............  October 29, 2003.
>=65,000 Btu/h and <135,000 Btu/h....  No Heating or Electric   EER = 12.1.............  June 1, 2013.
                                        Resistance Heating.
>=65,000 Btu/h and <135,000 Btu/h....  All Other Types of       EER = 11.9.............  June 1, 2013.
                                        Heating.
>=135,000 Btu/h and <240,000 Btu/h...  No Heating or Electric   EER = 12.5.............  June 1, 2014.
                                        Resistance Heating.
>=135,000 Btu/h and <240,000 Btu/h...  All Other Types of       EER = 12.3.............  June 1, 2014.
                                        Heating.
>=240,000 Btu/h and <760,000 Btu/h...  No Heating or Electric   EER = 12.4.............  June 1, 2014.
                                        Resistance Heating.
>=240,000 Btu/h and <760,000 Btu/h...  All Other Types of       EER = 12.2.............  June 1, 2014.
                                        Heating.
----------------------------------------------------------------------------------------------------------------


 Table 3 to Paragraph (b)--Minimum Cooling Efficiency Standards for Evaporatively-Cooled Commercial Package Air
                                             Conditioning Equipment
----------------------------------------------------------------------------------------------------------------
                                                                                             Compliance date:
           Cooling capacity             Supplementary heating      Minimum efficiency     equipment manufactured
                                                 type                                       starting on . . .
----------------------------------------------------------------------------------------------------------------
                       Evaporatively-Cooled Commercial Package Air Conditioning Equipment
----------------------------------------------------------------------------------------------------------------
<65,000 Btu/h........................  All....................  EER = 12.1.............  October 29, 2003.
>=65,000 Btu/h and <135,000 Btu/h....  No Heating or Electric   EER = 12.1.............  June 1, 2013.
                                        Resistance Heating.
>=65,000 Btu/h and <135,000 Btu/h....  All Other Types of       EER = 11.9.............  June 1, 2013.
                                        Heating.
>=135,000 Btu/h and <240,000 Btu/h...  No Heating or Electric   EER = 12.0.............  June 1, 2014.
                                        Resistance Heating.
>=135,000 Btu/h and <240,000 Btu/h...  All Other Types of       EER = 11.8.............  June 1, 2014.
                                        Heating.
>=240,000 Btu/h and <760,000 Btu/h...  No Heating or Electric   EER = 11.9.............  June 1, 2014.
                                        Resistance Heating.
>=240,000 Btu/h and <760,000 Btu/h...  All Other Types of       EER = 11.7.............  June 1, 2014.
                                        Heating.
----------------------------------------------------------------------------------------------------------------


     Table 4 to Paragraph (b)--Minimum Efficiency Standards for Double-Duct Air Conditioners and Heat Pumps
----------------------------------------------------------------------------------------------------------------
                                                                                              Compliance date:
                                                    Supplementary     Minimum efficiency         equipment
       Cooling capacity            Subcategory      heating type             \1\           manufactured starting
                                                                                                  on . . .
----------------------------------------------------------------------------------------------------------------
                                   Double-Duct Air Conditioners and Heat Pumps
----------------------------------------------------------------------------------------------------------------
>=65,000 Btu/h and <135,000     AC..............  Electric          EER = 11.2...........  January 1, 2010.
 Btu/h.                                            Resistance
                                                   Heating or No
                                                   Heating.
>=65,000 Btu/h and <135,000     AC..............  All Other Types   EER = 11.0...........  January 1, 2010.
 Btu/h.                                            of Heating.
>=65,000 Btu/h and <135,000     HP..............  Electric          EER = 11.0...........  January 1, 2010.
 Btu/h.                                            Resistance       COP = 3.3............
                                                   Heating or No
                                                   Heating.
>=65,000 Btu/h and <135,000     HP..............  All Other Types   EER = 10.8...........  January 1, 2010.
 Btu/h.                                            of Heating.      COP = 3.3............
>=135,000 Btu/h and <240,000    AC..............  Electric          EER = 11.0...........  January 1, 2010.
 Btu/h.                                            Resistance
                                                   Heating or No
                                                   Heating.
>=135,000 Btu/h and <240,000    AC..............  All Other Types   EER = 10.8...........  January 1, 2010.
 Btu/h.                                            of Heating.
>=135,000 Btu/h and <240,000    HP..............  Electric          EER = 10.6...........  January 1, 2010.
 Btu/h.                                            Resistance       COP = 3.2............
                                                   Heating or No
                                                   Heating.
>=135,000 Btu/h and <240,000    HP..............  All Other Types   EER = 10.4...........  January 1, 2010.
 Btu/h.                                            of Heating.      COP = 3.2............
>=240,000 Btu/h and <300,000    AC..............  Electric          EER = 10.0...........  January 1, 2010.
 Btu/h.                                            Resistance
                                                   Heating or No
                                                   Heating.
>=240,000 Btu/h and <300,000    AC..............  All Other Types   EER = 9.8............  January 1, 2010.
 Btu/h.                                            of Heating.
>=240,000 Btu/h and <300,000    HP..............  Electric          EER = 9.5............  January 1, 2010.
 Btu/h.                                            Resistance       COP = 3.2............
                                                   Heating or No
                                                   Heating.
>=240,000 Btu/h and <300,000    HP..............  All Other Types   EER = 9.3............  January 1, 2010.
 Btu/h.                                            of Heating.      COP = 3.2............
----------------------------------------------------------------------------------------------------------------
\1\ See section 3 of appendix A to this subpart for the test conditions upon which the COP standards are based.

    (c) Each water-source heat pump manufactured starting on the 
compliance date listed in table 5 to this paragraph (c) must meet the 
applicable minimum energy efficiency standard level(s) set forth in 
this paragraph (c).

[[Page 44040]]



 Table 5 to Paragraph (c)--Minimum Efficiency Standards for Water-Source
                  Heat Pumps (Water-to-Air, Water-Loop)
------------------------------------------------------------------------
                                                       Compliance date:
                                                           equipment
        Cooling capacity          Minimum efficiency     manufactured
                                                       starting on . . .
------------------------------------------------------------------------
           Water-Source Heat Pumps (Water-to-Air, Water-Loop)
------------------------------------------------------------------------
<17,000 Btu/h...................  EER = 12.2........  October 9, 2015.
                                  COP = 4.3.........
>=17,000 Btu/h and <65,000 Btu/h  EER = 13.0........  October 9, 2015.
                                  COP = 4.3.........
>=65,000 Btu/h and <135,000 Btu/  EER = 13.0........  October 9, 2015.
 h.                               COP = 4.3.........
------------------------------------------------------------------------

    (d) Each non-standard size packaged terminal air conditioner (PTAC) 
and packaged terminal heat pump (PTHP) manufactured on or after October 
7, 2010, must meet the applicable minimum energy efficiency standard 
level(s) set forth in table 6 to this paragraph (d). Each standard size 
PTAC manufactured on or after October 8, 2012, and before January 1, 
2017, must meet the applicable minimum energy efficiency standard 
level(s) set forth in table 6. Each standard size PTHP manufactured on 
or after October 8, 2012, must meet the applicable minimum energy 
efficiency standard level(s) set forth in table 6. Each standard size 
PTAC manufactured on or after January 1, 2017, must meet the applicable 
minimum energy efficiency standard level(s) set forth in table 7 to 
this paragraph (d).

                                        Table 6 to Paragraph (d)--Minimum Efficiency Standards for PTAC and PTHP
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                 Compliance date: products manufactured
      Equipment type                     Category                  Cooling capacity        Efficiency level                on and after . . .
--------------------------------------------------------------------------------------------------------------------------------------------------------
PTAC......................  Standard Size.....................  <7,000 Btu/h..........  EER = 11.7............  October 8, 2012.\2\
                                                                >=7,000 Btu/h and       EER = 13.8-(0.3 x Cap   October 8, 2012.\2\
                                                                 <=15,000 Btu/h.         \1\).
                                                                >15,000 Btu/h.........  EER = 9.3.............  October 8, 2012.\2\
                            Non-Standard Size.................  <7,000 Btu/h..........  EER = 9.4.............  October 7, 2010.
                                                                >=7,000 Btu/h and       EER = 10.9-(0.213 x     October 7, 2010.
                                                                 <=15,000 Btu/h.         Cap \1\).
                                                                >15,000 Btu/h.........  EER = 7.7.............  October 7, 2010.
PTHP......................  Standard Size.....................  <7,000 Btu/h..........  EER = 11.9............  October 8, 2012.
                                                                                        COP = 3.3.............
                                                                >=7,000 Btu/h and       EER = 14.0-(0.3 x Cap   October 8, 2012.
                                                                 <=15,000 Btu/h.         \1\).
                                                                                        COP = 3.7-(0.052 x Cap
                                                                                         \1\).
                                                                >15,000 Btu/h.........  EER = 9.5.............  October 8, 2012.
                                                                                        COP = 2.9.............
                            Non-Standard Size.................  <7,000 Btu/h..........  EER = 9.3.............  October 7, 2010.
                                                                                        COP = 2.7.............
                                                                >=7,000 Btu/h and       EER = 10.8-(0.213 x     October 7, 2010.
                                                                 <=15,000 Btu/h.         Cap \1\).
                                                                                        COP = 2.9-(0.026 x Cap
                                                                                         \1\).
                                                                >15,000 Btu/h.........  EER = 7.6.............  October 7, 2010.
                                                                                        COP = 2.5.............
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ ``Cap'' means cooling capacity in thousand Btu/h at 95 [deg]F outdoor dry-bulb temperature.
\2\ And manufactured before January 1, 2017. See table 7 to this paragraph (d) for updated efficiency standards that apply to this category of equipment
  manufactured on and after January 1, 2017.


                                         Table 7 to Paragraph (d)--Updated Minimum Efficiency Standards for PTAC
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                 Compliance date: products manufactured
      Equipment type                     Category                  Cooling capacity        Efficiency level                on and after . . .
--------------------------------------------------------------------------------------------------------------------------------------------------------
PTAC......................  Standard Size.....................  <7,000 Btu/h..........  EER = 11.9............  January 1, 2017.
                                                                >=7,000 Btu/h and       EER = 14.0-(0.3 x Cap   January 1, 2017.
                                                                 <=15,000 Btu/h.         \1\).
                                                                >15,000 Btu/h.........  EER = 9.5.............  January 1, 2017.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ ``Cap'' means cooling capacity in thousand Btu/h at 95 [deg]F outdoor dry-bulb temperature.

    (e)(1) Each single package vertical air conditioner and single 
package vertical heat pump manufactured on or after January 1, 2010, 
but before October 9, 2015 (for models >=65,000 Btu/h and <135,000 Btu/
h), or October 9, 2016 (for models >=135,000 Btu/h and <240,000 Btu/h), 
must meet the applicable minimum energy conservation standard level(s) 
set forth in this paragraph (e)(1).

[[Page 44041]]



   Table 8 to Paragraph (e)(1)--Minimum Efficiency Standards for Single Package Vertical Air Conditioners and
                                       Single Package Vertical Heat Pumps
----------------------------------------------------------------------------------------------------------------
                                                                                                Compliance date:
                                                                                                    products
         Equipment type           Cooling capacity       Sub-category       Efficiency level    manufactured on
                                                                                                and after . . .
----------------------------------------------------------------------------------------------------------------
Single package vertical air      <65,000 Btu/h.....  AC.................  EER = 9.0..........  January 1, 2010.
 conditioners and single                             HP.................  EER = 9.0..........  January 1, 2010.
 package vertical heat pumps,                                             COP = 3.0..........
 single-phase and three-phase.
Single package vertical air      >=65,000 Btu/h and  AC.................  EER = 8.9..........  January 1, 2010.
 conditioners and single          <135,000 Btu/h.    HP.................  EER = 8.9..........  January 1, 2010.
 package vertical heat pumps.                                             COP = 3.0..........
Single package vertical air      >=135,000 Btu/h     AC.................  EER = 8.6..........  January 1, 2010.
 conditioners and single          and <240,000 Btu/  HP.................  EER = 8.6..........  January 1, 2010.
 package vertical heat pumps.     h.                                      COP = 2.9..........
----------------------------------------------------------------------------------------------------------------

    (2) Each single package vertical air conditioner and single package 
vertical heat pump manufactured on and after October 9, 2015 (for 
models >=65,000 Btu/h and <135,000 Btu/h), or October 9, 2016 (for 
models >=135,000 Btu/h and <240,000 Btu/h), but before September 23, 
2019, must meet the applicable minimum energy conservation standard 
level(s) set forth in this paragraph (e)(2).

   Table 9 to Paragraph (e)(2)--Minimum Efficiency Standards for Single Package Vertical Air Conditioners and
                                       Single Package Vertical Heat Pumps
----------------------------------------------------------------------------------------------------------------
                                                                                                Compliance date:
                                                                                                    products
         Equipment type           Cooling capacity       Sub-category       Efficiency level    manufactured on
                                                                                                and after . . .
----------------------------------------------------------------------------------------------------------------
Single package vertical air      <65,000 Btu/h.....  AC.................  EER = 9.0..........  January 1, 2010.
 conditioners and single                             HP.................  EER = 9.0..........  January 1, 2010.
 package vertical heat pumps,                                             COP = 3.0..........
 single-phase and three-phase.
Single package vertical air      >=65,000 Btu/h and  AC.................  EER = 10.0.........  October 9, 2015.
 conditioners and single          <135,000 Btu/h.    HP.................  EER = 10.0.........  October 9, 2015.
 package vertical heat pumps.                                             COP = 3.0..........
Single package vertical air      >=135,000 Btu/h     AC.................  EER = 10.0.........  October 9, 2016.
 conditioners and single          and <240,000 Btu/  HP.................  EER = 10.0.........  October 9, 2016.
 package vertical heat pumps.     h.                                      COP = 3.0..........
----------------------------------------------------------------------------------------------------------------

    (3) Each single package vertical air conditioner and single package 
vertical heat pump manufactured on and after September 23, 2019, must 
meet the applicable minimum energy conservation standard level(s) set 
forth in this paragraph (e)(3).

 Table 10 to Paragraph (e)(3)--Updated Minimum Efficiency Standards for Single Package Vertical Air Conditioners
                                     and Single Package Vertical Heat Pumps
----------------------------------------------------------------------------------------------------------------
                                                                                                Compliance date:
                                                                                                    products
         Equipment type           Cooling  capacity      Sub-category       Efficiency level    manufactured on
                                                                                                and after . . .
----------------------------------------------------------------------------------------------------------------
Single package vertical air      <65,000 Btu/h.....  AC.................  EER = 11.0.........  September 23,
 conditioners and single                             HP.................  EER = 11.0.........   2019.
 package vertical heat pumps,                                             COP = 3.3..........  September 23,
 single-phase and three-phase.                                                                  2019.
Single package vertical air      >=65,000 Btu/h and  AC.................  EER = 10.0.........  October 9, 2015.
 conditioners and single          <135,000 Btu/h.    HP.................  EER = 10.0.........  October 9, 2015.
 package vertical heat pumps.                                             COP = 3.0..........
Single package vertical air      >=135,000 Btu/h     AC.................  EER = 10.0.........  October 9, 2016.
 conditioners and single          and <240,000 Btu/  HP.................  EER = 10.0.........  October 9, 2016.
 package vertical heat pumps.     h.                                      COP = 3.0..........
----------------------------------------------------------------------------------------------------------------

    (f)(1) Each computer room air conditioner with a net sensible 
cooling capacity less than 65,000 Btu/h manufactured on or after 
October 29, 2012, and before May 28, 2024 and each computer room air 
conditioner with a net sensible cooling capacity greater than or equal 
to 65,000 Btu/h and less than 760,000 Btu/h manufactured on or after 
October 29, 2013, and before May 28, 2024, must meet the applicable 
minimum energy efficiency standard level(s) set forth in this paragraph 
(f)(1).

[[Page 44042]]



          Table 11 to Paragraph (f)(1)--Minimum Efficiency Standards for Computer Room Air Conditioners
----------------------------------------------------------------------------------------------------------------
                                                                                      Minimum SCOP efficiency
               Equipment type                   Net sensible cooling capacity    -------------------------------
                                                                                     Downflow         Upflow
----------------------------------------------------------------------------------------------------------------
Air-Cooled.................................  <65,000 Btu/h......................            2.20            2.09
                                             >=65,000 Btu/h and <240,000 Btu/h..            2.10            1.99
                                             >=240,000 Btu/h and <760,000 Btu/h.            1.90            1.79
Water-Cooled...............................  <65,000 Btu/h......................            2.60            2.49
                                             >=65,000 Btu/h and <240,000 Btu/h..            2.50            2.39
                                             >=240,000 Btu/h and <760,000 Btu/h.            2.40            2.29
Water-Cooled with Fluid Economizer.........  <65,000 Btu/h......................            2.55            2.44
                                             >=65,000 Btu/h and <240,000 Btu/h..            2.45            2.34
                                             >=240,000 Btu/h and <760,000 Btu/h.            2.35            2.24
Glycol-Cooled..............................  <65,000 Btu/h......................            2.50            2.39
                                             >=65,000 Btu/h and <240,000 Btu/h..            2.15            2.04
                                             >=240,000 Btu/h and <760,000 Btu/h.            2.10            1.99
Glycol-Cooled with Fluid Economizer........  <65,000 Btu/h......................            2.45            2.34
                                             >=65,000 Btu/h and <240,000 Btu/h..            2.10            1.99
                                             >=240,000 Btu/h and <760,000 Btu/h.            2.05            1.94
----------------------------------------------------------------------------------------------------------------

    (2) Each computer room air conditioner manufactured on or after May 
28, 2024, must meet the applicable minimum energy efficiency standard 
level(s) set forth in this paragraph (f)(2).

                   Table 12 to Paragraph (f)(2)--Updated Minimum Efficiency Standards for Floor-Mounted Computer Room Air Conditioners
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                    Downflow and upflow ducted                           Upflow non-ducted and horizontal flow
                                   ---------------------------------------------------------------------------------------------------------------------
                                                                 Minimum NSenCOP efficiency                                 Minimum NSenCOP efficiency
          Equipment type               Net sensible cooling   --------------------------------    Net sensible cooling   -------------------------------
                                             capacity                                                   capacity           Upflow  non-     Horizontal
                                                                  Downflow      Upflow ducted                                 ducted           flow
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air-Cooled........................  <80,000 Btu/h............            2.70            2.67  <65,000 Btu/h............            2.16            2.65
                                    >=80,000 Btu/h and                   2.58            2.55  >=65,000 Btu/h and                   2.04            2.55
                                     <295,000 Btu/h.                                            <240,000 Btu/h.
                                    >=295,000 Btu/h and                  2.36            2.33  >=240,000 Btu/h and                  1.89            2.47
                                     <930,000 Btu/h.                                            <760,000 Btu/h.
Air-Cooled with Fluid Economizer..  <80,000 Btu/h............            2.70            2.67  <65,000 Btu/h............            2.09            2.65
                                    >=80,000 Btu/h and                   2.58            2.55  >=65,000 Btu/h and                   1.99            2.55
                                     <295,000 Btu/h.                                            <240,000 Btu/h.
                                    >=295,000 Btu/h and                  2.36            2.33  >=240,000 Btu/h and                  1.81            2.47
                                     <930,000 Btu/h.                                            <760,000 Btu/h.
Water-Cooled......................  <80,000 Btu/h............            2.82            2.79  <65,000 Btu/h............            2.43            2.79
                                    >=80,000 Btu/h and                   2.73            2.70  >=65,000 Btu/h and                   2.32            2.68
                                     <295,000 Btu/h.                                            <240,000 Btu/h.
                                    >=295,000 Btu/h and                  2.67            2.64  >=240,000 Btu/h and                  2.20            2.60
                                     <930,000 Btu/h.                                            <760,000 Btu/h.
Water-Cooled with Fluid Economizer  <80,000 Btu/h............            2.77            2.74  <65,000 Btu/h............            2.35            2.71
                                    >=80,000 Btu/h and                   2.68            2.65  >=65,000 Btu/h and                   2.24            2.60
                                     <295,000 Btu/h.                                            <240,000 Btu/h.
                                    >=295,000 Btu/h and                  2.61            2.58  >=240,000 Btu/h and                  2.12            2.54
                                     <930,000 Btu/h.                                            <760,000 Btu/h.
Glycol-Cooled.....................  <80,000 Btu/h............            2.56            2.53  <65,000 Btu/h............            2.08            2.48
                                    >=80,000 Btu/h and                   2.24            2.21  >=65,000 Btu/h and                   1.90            2.18
                                     <295,000 Btu/h.                                            <240,000 Btu/h.
                                    >=295,000 Btu/h and                  2.21            2.18  >=240,000 Btu/h and                  1.81            2.18
                                     <930,000 Btu/h.                                            <760,000 Btu/h.
Glycol-Cooled with Fluid            <80,000 Btu/h............            2.51            2.48  <65,000 Btu/h............            2.00            2.44
 Economizer.
                                    >=80,000 Btu/h and                   2.19            2.16  >=65,000 Btu/h and                   1.82            2.10
                                     <295,000 Btu/h.                                            <240,000 Btu/h.
                                    >=295,000 Btu/h and                  2.15            2.12  >=240,000 Btu/h and                  1.73            2.10
                                     <930,000 Btu/h.                                            <760,000 Btu/h.
--------------------------------------------------------------------------------------------------------------------------------------------------------


  Table 13 to Paragraph (f)(2)--Minimum Efficiency Standards for Ceiling-Mounted Computer Room Air Conditioners
----------------------------------------------------------------------------------------------------------------
                                                                                    Minimum NSenCOP efficiency
               Equipment type                   Net sensible cooling capacity    -------------------------------
                                                                                      Ducted        Non-ducted
----------------------------------------------------------------------------------------------------------------
Air-Cooled with Free Air Discharge           <29,000 Btu/h......................            2.05            2.08
 Condenser.

[[Page 44043]]

 
                                             >=29,000 Btu/h and <65,000 Btu/h...            2.02            2.05
                                             >=65,000 Btu/h and <760,000 Btu/h..            1.92            1.94
Air-Cooled with Free Air Discharge           <29,000 Btu/h......................            2.01            2.04
 Condenser and Fluid Economizer.
                                             >=29,000 Btu/h and <65,000 Btu/h...            1.97               2
                                             >=65,000 Btu/h and <760,000 Btu/h..            1.87            1.89
Air-Cooled with Ducted Condenser...........  <29,000 Btu/h......................            1.86            1.89
                                             >=29,000 Btu/h and <65,000 Btu/h...            1.83            1.86
                                             >=65,000 Btu/h and <760,000 Btu/h..            1.73            1.75
Air-Cooled with Fluid Economizer and Ducted  <29,000 Btu/h......................            1.82            1.85
 Condenser.
                                             >=29,000 Btu/h and <65,000 Btu/h...            1.78            1.81
                                             >=65,000 Btu/h and <760,000 Btu/h..            1.68             1.7
Water-Cooled...............................  <29,000 Btu/h......................            2.38            2.41
                                             >=29,000 Btu/h and <65,000 Btu/h...            2.28            2.31
                                             >=65,000 Btu/h and <760,000 Btu/h..            2.18             2.2
Water-Cooled with Fluid Economizer.........  <29,000 Btu/h......................            2.33            2.36
                                             >=29,000 Btu/h and <65,000 Btu/h...            2.23            2.26
                                             >=65,000 Btu/h and <760,000 Btu/h..            2.13            2.16
Glycol-Cooled..............................  <29,000 Btu/h......................            1.97               2
                                             >=29,000 Btu/h and <65,000 Btu/h...            1.93            1.98
                                             >=65,000 Btu/h and <760,000 Btu/h..            1.78            1.81
Glycol-Cooled with Fluid Economizer........  <29,000 Btu/h......................            1.92            1.95
                                             >=29,000 Btu/h and <65,000 Btu/h...            1.88            1.93
                                             >=65,000 Btu/h and <760,000 Btu/h..            1.73            1.76
----------------------------------------------------------------------------------------------------------------

    (g)(1) Each variable refrigerant flow air conditioner or heat pump 
manufactured on or after the compliance date listed in table 14 to this 
paragraph (g)(1) and prior to January 1, 2024, must meet the applicable 
minimum energy efficiency standard level(s) set forth in this paragraph 
(g)(1).

    Table 14 to Paragraph (g)(1)--Minimum Efficiency Standards for Variable Refrigerant Flow Multi-Split Air
                                           Conditioners and Heat Pumps
----------------------------------------------------------------------------------------------------------------
                                                                                               Compliance date:
                                                                                                   equipment
         Equipment type            Cooling capacity    Heating type \1\    Efficiency level     manufactured on
                                                                                                and after . . .
----------------------------------------------------------------------------------------------------------------
VRF Multi-Split Air Conditioners  >=65,000 Btu/h and  No Heating or       11.2 EER..........  January 1, 2010.
 (Air-Cooled).                     <135,000 Btu/h.     Electric
                                                       Resistance
                                                       Heating.
                                                      All Other Types of  11.0 EER..........  January 1, 2010.
                                                       Heating.
                                  >=135,000 Btu/h     No Heating or       11.0 EER..........  January 1, 2010.
                                   and <240,000 Btu/   Electric
                                   h.                  Resistance
                                                       Heating.
                                                      All Other Types of  10.8 EER..........  January 1, 2010.
                                                       Heating.
                                  >=240,000 Btu/h     No Heating or       10.0 EER..........  January 1, 2010.
                                   and <760,000 Btu/   Electric
                                   h.                  Resistance
                                                       Heating.
                                                      All Other Types of  9.8 EER...........  January 1, 2010.
                                                       Heating.
VRF Multi-Split Heat Pumps (Air-  >=65,000 Btu/h and  No Heating or       11.0 EER, 3.3 COP.  January 1, 2010.
 Cooled).                          <135,000 Btu/h.     Electric
                                                       Resistance
                                                       Heating.
                                                      All Other Types of  10.8 EER, 3.3 COP.  January 1, 2010.
                                                       Heating.
                                  >=135,000 Btu/h     No Heating or       10.6 EER, 3.2 COP.  January 1, 2010.
                                   and <240,000 Btu/   Electric
                                   h.                  Resistance
                                                       Heating.
                                                      All Other Types of  10.4 EER, 3.2 COP.  January 1, 2010.
                                                       Heating.
                                  >=240,000 Btu/h     No Heating or       9.5 EER, 3.2 COP..  January 1, 2010.
                                   and <760,000 Btu/   Electric
                                   h.                  Resistance
                                                       Heating.
                                                      All Other Types of  9.3 EER, 3.2 COP..  January 1, 2010.
                                                       Heating.
VRF Multi-Split Heat Pumps        <17,000 Btu/h.....  Without Heat        12.0 EER, 4.2 COP.  October 29, 2012.
 (Water-Source).                                       Recovery.                              October 29, 2003.
                                                      With Heat Recovery  11.8 EER, 4.2 COP.  October 29, 2012.
                                                                                              October 29, 2003.
                                  >=17,000 Btu/h and  All.                12.0 EER, 4.2 COP.  October 29, 2003.
                                   <65,000 Btu/h.
                                  >=65,000 Btu/h and  All.                12.0 EER, 4.2 COP.  October 29, 2003.
                                   <135,000 Btu/h.
                                  >=135,000 Btu/h     Without Heat        10.0 EER, 3.9 COP.  October 29, 2013.
                                   and <760,000 Btu/   Recovery.
                                   h.

[[Page 44044]]

 
                                                      With Heat Recovery  9.8 EER, 3.9 COP..  October 29, 2013.
----------------------------------------------------------------------------------------------------------------
\1\ VRF multi-split heat pumps (air-cooled) with heat recovery fall under the category of ``All Other Types of
  Heating'' unless they also have electric resistance heating, in which case it falls under the category for
  ``No Heating or Electric Resistance Heating.''

    (2) Each variable refrigerant flow air conditioner or heat pump 
(except air-cooled systems with cooling capacity less than 65,000 Btu/
h) manufactured on or after January 1, 2024, must meet the applicable 
minimum energy efficiency standard level(s) set forth in this paragraph 
(g)(2).

Table 15 to Paragraph (g)(2)--Updated Minimum Efficiency Standards for Variable Refrigerant Flow Multi-Split Air
                                           Conditioners and Heat Pumps
----------------------------------------------------------------------------------------------------------------
           Equipment type                   Size category              Heating type         Minimum efficiency
----------------------------------------------------------------------------------------------------------------
VRF Multi-Split Air Conditioners     >=65,000 and <135,000 Btu/h  All...................  15.5 IEER.
 (Air-Cooled).
                                     >=135,000 and <240,000 Btu/  All...................  14.9 IEER.
                                      h.
                                     >=240,000 Btu/h and          All...................  13.9 IEER.
                                      <760,000 Btu/h.
VRF Multi-Split Heat Pumps (Air-     >=65,000 and <135,000 Btu/h  Heat Pump without Heat  14.6 IEER, 3.3 COP.
 Cooled).                                                          Recovery.
                                                                  Heat Pump with Heat     14.4 IEER, 3.3 COP.
                                                                   Recovery.
                                     >=135,000 and <240,000 Btu/  Heat Pump without Heat  13.9 IEER, 3.2 COP.
                                      h.                           Recovery.              13.7 IEER, 3.2 COP.
                                                                  Heat Pump with Heat
                                                                   Recovery.
                                     >=240,000 Btu/h and          Heat Pump without Heat  12.7 IEER, 3.2 COP.
                                      <760,000 Btu/h.              Recovery.              12.5 IEER, 3.2 COP.
                                                                  Heat Pump with Heat
                                                                   Recovery.
VRF Multi-Split Heat Pumps (Water-   <65,000 Btu/h..............  Heat Pump without Heat  16.0 IEER, 4.3 COP.
 Source).                                                          Recovery.              15.8 IEER, 4.3 COP.
                                                                  Heat Pump with Heat
                                                                   Recovery.
                                     >=65,000 and <135,000 Btu/h  Heat Pump without Heat  16.0 IEER, 4.3 COP.
                                                                   Recovery.              15.8 IEER, 4.3 COP.
                                                                  Heat Pump with Heat
                                                                   Recovery.
                                     >=135,000 and <240,000 Btu/  Heat Pump without Heat  14.0 IEER, 4.0 COP.
                                      h.                           Recovery.              13.8 IEER, 4.0 COP.
                                                                  Heat Pump with Heat
                                                                   Recovery.
                                     >=240,000 Btu/h and          Heat Pump without Heat  12.0 IEER, 3.9 COP.
                                      <760,000 Btu/h.              Recovery.              11.8 IEER, 3.9 COP.
                                                                  Heat Pump with Heat
                                                                   Recovery.
----------------------------------------------------------------------------------------------------------------

    (h) Each direct expansion-dedicated outdoor air system manufactured 
on or after the compliance date listed in table 16 to this paragraph 
(h) must meet the applicable minimum energy efficiency standard 
level(s) set forth in this paragraph (h).

   Table 16 to Paragraph (h)--Minimum Efficiency Standards for Direct Expansion-Dedicated Outdoor Air Systems
----------------------------------------------------------------------------------------------------------------
                                                                                             Compliance date:
         Equipment Category                  Subcategory             Efficiency level     equipment manufactured
                                                                                             starting on . . .
----------------------------------------------------------------------------------------------------------------
Direct expansion-dedicated outdoor   (AC)--Air-cooled without     ISMRE2 = 3.8..........  May 1, 2024.
 air systems.                         ventilation energy
                                      recovery systems.
                                     (AC w/VERS)--Air-cooled      ISMRE2 = 5.0..........  May 1, 2024.
                                      with ventilation energy
                                      recovery systems.
                                     (ASHP)--Air-source heat      ISMRE2 = 3.8..........  May 1, 2024.
                                      pumps without ventilation   ISCOP2 = 2.05.........
                                      energy recovery systems.
                                     (ASHP w/VERS)--Air-source    ISMRE2 = 5.0..........  May 1, 2024.
                                      heat pumps with             ISCOP2 = 3.20.........
                                      ventilation energy
                                      recovery systems.
                                     (WC)--Water-cooled without   ISMRE2 = 4.7..........  May 1, 2024.
                                      ventilation energy
                                      recovery systems.
                                     (WC w/VERS)--Water-cooled    ISMRE2 = 5.1..........  May 1, 2024.
                                      with ventilation energy
                                      recovery systems.

[[Page 44045]]

 
                                     (WSHP)--Water-source heat    ISMRE2 = 3.8..........  May 1, 2024.
                                      pumps without ventilation   ISCOP2 = 2.13.........
                                      energy recovery systems.
                                     (WSHP w/VERS)--Water-source  ISMRE2 = 4.6..........  May 1, 2024.
                                      heat pumps with             ISCOP2 = 4.04.........
                                      ventilation energy
                                      recovery systems.
----------------------------------------------------------------------------------------------------------------

    (i) Air-cooled, three-phase, commercial package air conditioning 
and heating equipment with a cooling capacity of less than 65,000 Btu/h 
and air-cooled, three-phase variable refrigerant flow multi-split air 
conditioning and heating equipment with a cooling capacity of less than 
65,000 Btu/h manufactured on or after the compliance date listed in 
tables 17 and 18 to this paragraph (i) must meet the applicable minimum 
energy efficiency standard level(s) set forth in this paragraph (i).

   Table 17 to Paragraph (i)--Minimum Efficiency Standards for Air-Cooled, Three-Phase, Commercial Package Air
   Conditioning and Heating Equipment With a Cooling Capacity of Less Than 65,000 Btu/h and Air-Cooled, Three-
    Phase, Small Variable Refrigerant Flow Multi-Split Air Conditioning and Heating Equipment With a Cooling
                                       Capacity of Less Than 65,000 Btu/h
----------------------------------------------------------------------------------------------------------------
                                                                                               Compliance date:
                                                                                                   equipment
         Equipment type            Cooling capacity       Subcategory     Minimum efficiency     manufactured
                                                                                               starting on . . .
----------------------------------------------------------------------------------------------------------------
Commercial Package Air            <65,000 Btu/h.....  Split-System......  13.0 SEER.........  June 16, 2008.\1\
 Conditioning Equipment.
Commercial Package Air            <65,000 Btu/h.....  Single-Package....  14.0 SEER.........  January 1,
 Conditioning Equipment.                                                                       2017.\1\
Commercial Package Air            <65,000 Btu/h.....  Split-System......  14.0 SEER.........  January 1,
 Conditioning and Heating                                                 8.2 HSPF..........   2017.\1\
 Equipment.
Commercial Package Air            <65,000 Btu/h.....  Single-Package....  14.0 SEER.........  January 1,
 Conditioning and Heating                                                 8.0 HSPF..........   2017.\1\
 Equipment.
VRF Air Conditioners............  <65,000 Btu/h.....  ..................  13.0 SEER.........  June 16, 2008.\1\
VRF Heat Pumps..................  <65,000 Btu/h.....  ..................  13.0 SEER.........  June 16, 2008.\1\
                                                                          7.7 HSPF..........
----------------------------------------------------------------------------------------------------------------
\1\ And manufactured before January 1, 2025. For equipment manufactured on or after January 1, 2025, see table
  18 to this paragraph (i) for updated efficiency standards.


 Table 18 to Paragraph (i)--Updated Minimum Efficiency Standards for Air-Cooled, Three-Phase, Commercial Package
 Air Conditioning and Heating Equipment With a Cooling Capacity of Less Than 65,000 Btu/h and Air-Cooled, Three-
    Phase, Small Variable Refrigerant Flow Multi-Split Air Conditioning and Heating Equipment With a Cooling
                                       Capacity of Less Than 65,000 Btu/h
----------------------------------------------------------------------------------------------------------------
                                                                                               Compliance date:
                                                                                                   equipment
         Equipment type            Cooling capacity       Subcategory     Minimum efficiency     manufactured
                                                                                               starting on. . .
----------------------------------------------------------------------------------------------------------------
Commercial Package Air            < 65,000 Btu/h....  Split-System......  13.4 SEER2........  January 1, 2025.
 Conditioning Equipment.
Commercial Package Air            < 65,000 Btu/h....  Single-Package....  13.4 SEER2........  January 1, 2025.
 Conditioning Equipment.
Commercial Package Air            < 65,000 Btu/h....  Split-System......  14.3 SEER2........  January 1, 2025.
 Conditioning and Heating                                                 7.5 HSPF2.........
 Equipment.
Commercial Package Air            < 65,000 Btu/h....  Single-Package....  13.4 SEER2........  January 1, 2025.
 Conditioning and Heating                                                 6.7 HSPF2.........
 Equipment.
Space-Constrained Commercial      <= 30,000 Btu/h...  Split-System......  12.7 SEER2........  January 1, 2025.
 Package Air Conditioning
 Equipment.
Space-Constrained Commercial      <= 30,000 Btu/h...  Single-Package....  13.9 SEER2........  January 1, 2025.
 Package Air Conditioning
 Equipment.
Space-Constrained Commercial      <= 30,000 Btu/h...  Split-System......  13.9 SEER2........  January 1, 2025.
 Package Air Conditioning and                                             7.0 HSPF2.........
 Heating Equipment.
Space-Constrained Commercial      <= 30,000 Btu/h...  Single-Package....  13.9 SEER2........  January 1, 2025.
 Package Air Conditioning and                                             6.7 HSPF2.........
 Heating Equipment.
Small-Duct, High-Velocity         < 65,000 Btu/h....  Split-System......  13.0 SEER2........  January 1, 2025.
 Commercial Package Air
 Conditioning.

[[Page 44046]]

 
Small-Duct, High-Velocity         < 65,000 Btu/h....  Split-System......  14.0 SEER2........  January 1, 2025.
 Commercial Package Air                                                   6.9 HSPF2.........
 Conditioning and Heating
 Equipment.
VRF Air Conditioners............  < 65,000 Btu/h....  ..................  13.4 SEER2........  January 1, 2025.
VRF Heat Pumps..................  < 65,000 Btu/h....  ..................  13.4 SEER2........  January 1, 2025.
                                                                          7.5 HSPF2.........
----------------------------------------------------------------------------------------------------------------


0
11. Appendix A to subpart F of part 431 is revised to read as follows:

Appendix A to Subpart F of Part 431--Uniform Test Method for the 
Measurement of Energy Consumption of Commercial Package Air 
Conditioning and Heating Equipment (Excluding Air-Cooled Equipment With 
a Cooling Capacity Less Than 65,000 Btu/h)

    Note: Prior to May 15, 2025, representations with respect to the 
energy use or efficiency of commercial package air conditioning and 
heating equipment (excluding air-cooled equipment with a cooling 
capacity less than 65,000 Btu/h), including compliance 
certifications, must be based on testing conducted in accordance 
with:
    (a) The applicable provisions (appendix A to subpart F of part 
431 for air-cooled equipment, and table 1 to Sec.  431.96 for water-
cooled and evaporatively-cooled equipment) as they appeared in 
subpart F of 10 CFR part 431, revised as of January 1, 2024; or
    (b) This appendix.
    Beginning May 15, 2025, and prior to the compliance date of 
amended standards for commercial package air conditioning and 
heating equipment (excluding air-cooled equipment with a cooling 
capacity less than 65,000 Btu/h) based on integrated ventilation, 
economizing, and cooling (IVEC) and integrated ventilation and 
heating efficiency (IVHE) (see Sec.  431.97), representations with 
respect to energy use or efficiency of commercial package air 
conditioning and heating equipment (excluding air-cooled equipment 
with a cooling capacity less than 65,000 Btu/h), including 
compliance certifications, must be based on testing conducted in 
accordance with this appendix.
    Beginning on the compliance date of amended standards for 
commercial package air conditioning and heating equipment (excluding 
equipment with a cooling capacity less than 65,000 Btu/h) based on 
IVEC and IVHE (see Sec.  431.97), representations with respect to 
energy use or efficiency of commercial package air conditioning and 
heating equipment (excluding air-cooled equipment with a cooling 
capacity less than 65,000 Btu/h), including compliance 
certifications, must be based on testing conducted in accordance 
with appendix A1 to this subpart.
    Manufacturers may also certify compliance with any amended 
energy conservation standards for commercial package air 
conditioning and heating equipment (excluding air-cooled equipment 
with a cooling capacity less than 65,000 Btu/h) based on IVEC or 
IVHE prior to the applicable compliance date for those standards 
(see Sec.  431.97), and those compliance certifications must be 
based on testing in accordance with appendix A1 to this subpart.

1. Incorporation by Reference

    DOE incorporated by reference in Sec.  431.95, the entire 
standard for AHRI 340/360-2022 and ANSI/ASHRAE 37-2009. However, 
certain enumerated provisions of AHRI 340/360-2022 and ANSI/ASHRAE 
37-2009, as set forth in this section 1 are inapplicable. To the 
extent there is a conflict between the terms or provisions of a 
referenced industry standard and the CFR, the CFR provisions 
control.
    1.1. AHRI 340/360-2022:
    (a) Section 1 Purpose is inapplicable,
    (b) Section 2 Scope is inapplicable,
    (c) The following subsections of Section 3 Definitions are 
inapplicable: 3.2 (Basic Model), 3.4 (Commercial and Industrial 
Unitary Air-conditioning Equipment), 3.5 (Commercial and Industrial 
Unitary Heat Pump), 3.7 (Double-duct System), 3.8 (Energy Efficiency 
Ratio (EER)), 3.12 (Heating Coefficient of Performance 
(COPH)), 3.14 (Integrated Energy Efficiency Ratio 
(IEER)), 3.23 (Published Rating), 3.26 (Single Package Air-
Conditioners), 3.27 (Single Package Heat Pumps), 3.29 (Split System 
Air-conditioners), 3.30 (Split System Heat Pump), 3.36 (Year Round 
Single Package Air-conditioners),
    (d) Section 7 Minimum Data Requirements for Published Ratings is 
inapplicable,
    (e) Section 8 Operating Requirements is inapplicable,
    (f) Section 9 Marking and Nameplate Data is inapplicable,
    (g) Section 10 Conformance Conditions is inapplicable,
    (h) Appendix B References--Informative is inapplicable,
    (i) Appendix D Unit Configuration for Standard Efficiency 
Determination--Normative is inapplicable,
    (j) Appendix F International Rating Conditions--Normative is 
inapplicable,
    (k) Appendix G Examples of IEER Calculations--Informative is 
inapplicable,
    (l) Appendix H Example of Determination of Fan and Motor 
Efficiency for Non-standard Integrated Indoor Fan and Motors--
Informative is inapplicable, and
    (m) Appendix I Double-duct System Efficiency Metrics with Non-
Zero Outdoor Air External Static Pressure (ESP)--Normative is 
inapplicable.
    1.2. ANSI/ASHRAE 37-2009:
    (a) Section 1 Purpose is inapplicable
    (b) Section 2 Scope is inapplicable, and
    (c) Section 4 Classifications is inapplicable.

2. General

    Determine the applicable energy efficiency metrics (IEER, EER, 
and COP) in accordance with this appendix and the applicable 
sections of AHRI 340/360-2022 and ANSI/ASHRAE 37-2009.
    Section 3 of this appendix provides additional instructions for 
testing. In cases where there is a conflict, the language of this 
appendix takes highest precedence, followed by AHRI 340/360-2022, 
followed by ANSI/ASHRAE 37-2009. Any subsequent amendment to a 
referenced document by the standard-setting organization will not 
affect the test procedure in this appendix, unless and until the 
test procedure is amended by DOE.

3. Test Conditions

    The following conditions specified in Table 6 of AHRI 340/360-
2022 apply when testing to certify to the energy conservation 
standards in Sec.  431.97. For cooling mode tests for equipment 
subject to standards in terms of EER, test using the ``Standard 
Rating Conditions Cooling''. For cooling mode tests for equipment 
subject to standards in terms of IEER, test using the ``Standard 
Rating Conditions Cooling'' and the ``Standard Rating Part-Load 
Conditions (IEER)''. For heat pump heating mode tests for equipment 
subject to standards in terms of COP, test using the ``Standard 
Rating Conditions (High Temperature Steady State Heating)''.
    For equipment subject to standards in terms of EER, 
representations of IEER made using the ``Standard Rating Part-Load 
Conditions (IEER)'' in Table 6 of AHRI 340/360-2022 are optional. 
For equipment

[[Page 44047]]

subject to standards in terms of IEER, representations of EER made 
using the ``Standard Rating Conditions Cooling'' in Table 6 of AHRI 
340/360-2022 are optional. Representations of COP made using the 
``Standard Rating Conditions (Low Temperature Steady State 
Heating)'' in Table 6 of AHRI 340/360-2022 are optional and are not 
to be used as the basis for determining compliance with energy 
efficiency standards in terms of COP.

0
12. Add appendix A1 to subpart F of part 431 to read as follows:

Appendix A1 to Subpart F of Part 431--Uniform Test Method for the 
Measurement of Energy Consumption of Commercial Package Air 
Conditioning and Heating Equipment (Excluding Air-Cooled Equipment With 
a Cooling Capacity Less Than 65,000 Btu/h)

    Note:  Prior to May 15, 2025, representations with respect to 
the energy use or efficiency of commercial package air conditioning 
and heating equipment (excluding air-cooled equipment with a cooling 
capacity less than 65,000 Btu/h), including compliance 
certifications, must be based on testing conducted in accordance 
with:
    (a) The applicable provisions (appendix A to subpart F of part 
431 for air-cooled equipment, and table 1 to Sec.  431.96 for water-
cooled and evaporatively-cooled equipment) as it appeared in subpart 
F of 10 CFR part 431, revised as of January 1, 2024; or
    (b) Appendix A to this subpart.
    Beginning May 15, 2025, and prior to the compliance date of 
amended standards for commercial package air conditioning and 
heating equipment (excluding air-cooled equipment with a cooling 
capacity less than 65,000 Btu/h) based on integrated ventilation, 
economizing, and cooling (IVEC) and integrated ventilation and 
heating efficiency (IVHE) (see Sec.  431.97), representations with 
respect to energy use or efficiency of commercial package air 
conditioning and heating equipment (excluding air-cooled equipment 
with a cooling capacity less than 65,000 Btu/h), including 
compliance certifications, must be based on testing conducted in 
accordance with appendix A to this subpart.
    Beginning on the compliance date of amended standards for 
commercial package air conditioning and heating equipment (excluding 
air-cooled equipment with a cooling capacity less than 65,000 Btu/h) 
based on IVEC and IVHE (see Sec.  431.97), representations with 
respect to energy use or efficiency of commercial package air 
conditioning and heating equipment (excluding air-cooled equipment 
with a cooling capacity less than 65,000 Btu/h), including 
compliance certifications, must be based on testing conducted in 
accordance with this appendix.
    Manufacturers may also certify compliance with any amended 
energy conservation standards for commercial package air 
conditioning and heating equipment (excluding air-cooled equipment 
with a cooling capacity less than 65,000 Btu/h) based on IVEC or 
IVHE prior to the applicable compliance date for those standards 
(see Sec.  431.97), and those compliance certifications must be 
based on testing in accordance with this appendix.

1. Incorporation by Reference

    DOE incorporated by reference in Sec.  431.95, the entire 
standard for AHRI 1340-2023 and ANSI/ASHRAE 37-2009. However, 
certain enumerated provisions of AHRI 1340-2023 and ANSI/ASHRAE 37-
2009, as listed in this section 1 are inapplicable. To the extent 
there is a conflict between the terms or provisions of a referenced 
industry standard and the CFR, the CFR provisions control.
    1.1. AHRI 1340-2023:
    (a) Section 1 Purpose is inapplicable,
    (b) Section 2 Scope is inapplicable,
    (c) The following subsections of section 3 Definitions are 
inapplicable: 3.2.2 (Barometric Relief Damper), 3.2.3 (Basic Model), 
3.2.5 (Commercial and Industrial Unitary Air-conditioner and Heat 
Pump Equipment), 3.2.5.1 (Commercial and Industrial Unitary Air-
Conditioning System), 3.2.5.2 (Commercial and Industrial Unitary 
Heat Pump System), 3.2.7 (Double-duct System), 3.2.9 (Desiccant 
Dehumidification Component), 3.2.10 (Drain Pan Heater), 3.2.11.1 
(Air Economizer), 3.2.12 (Energy Efficiency Ratio 2), 3.2.13 
(Evaporative Cooling), 3.2.13.1 (Direct Evaporative Cooling System), 
3.2.13.2 (Indirect Evaporative Cooling System), 3.2.14 (Fresh Air 
Damper), 3.2.15 (Fire, Smoke, or Isolation Damper), 3.2.17 (Hail 
Guard), 3.2.19 (Heating Coefficient of Performance 2 
(COP2H)), 3.2.20 (High-Effectiveness Indoor Air 
Filtration), 3.2.22 (Indoor Single Package Air-conditioners), 3.2.23 
(Integrated Ventilation, Economizing, and Cooling Efficiency 
(IVEC)), 3.2.34 (Integrated Ventilation and Heating Efficiency 
(IVHE)), 3.2.29 (Non-standard Ducted Condenser Fan), 3.2.31.2 
(Boost2 Heating Operating Level (B2)), 3.2.34 (Power Correction 
Capacitor), 3.2.35 (Powered Exhaust Air Fan), 3.2.36 (Powered Return 
Air Fan), 3.2.37 (Process Heat Recovery, Reclaim, or Thermal Storage 
Coil), 3.2.38 (Published Rating), 3.2.41 (Refrigerant Reheat Coil), 
3.2.42 (Single Package Air-conditioner), 3.2.43 (Single Package Heat 
Pumps), 3.2.44 (Single Package System), 3.2.45 (Sound Trap), 3.2.46 
(Split System), 3.2.51 (Steam or Hydronic Heat Coils), 3.2.53 (UV 
Lights), 3.2.55 (Ventilation Energy Recovery System (VERS)), 3.2.56 
(Year Round Single Package Air-conditioner), 3.2.57 (Year Round 
Single Package Heat Pump),
    (d) Subsection 5.2 (Optional System Features) of section 5 Test 
Requirements is inapplicable,
    (e) The following subsections of section 6 Rating Requirements 
are inapplicable: 6.4 (Rating Values), 6.5 (Uncertainty), and 6.6 
(Verification Testing),
    (f) Section 7 Minimum Data Requirements for Published Ratings is 
inapplicable,
    (g) Section 8 Operating Requirements is inapplicable,
    (h) Section 9 Marking and Nameplate Data is inapplicable,
    (i) Section 10 Conformance Conditions is inapplicable,
    (j) Appendix B References--Informative is inapplicable,
    (k) Sections D.1 (Purpose) and D.2 (Configuration Requirements) 
of Appendix D Unit Configuration for Standard Efficiency 
Determination--Normative are inapplicable,
    (l) Appendix F International Rating Conditions--Normative is 
inapplicable,
    (m) Appendix G Example of Determination of Fan and Motor 
Efficiency for Non-standard Integrated Indoor Fan and Motors--
Informative is inapplicable, and
    (n) Appendix H Determination of Low-temperature Cut-in and Cut-
out Temperatures--Normative is inapplicable.
    1.2. ANSI/ASHRAE 37-2009:
    (a) Section 1 Purpose is inapplicable
    (b) Section 2 Scope is inapplicable, and
    (c) Section 4 Classifications is inapplicable.

2. General

    For air conditioners and heat pumps, determine IVEC and IVHE (as 
applicable) in accordance with this appendix and the applicable 
sections of AHRI 1340-2023 and ANSI/ASHRAE 37-2009. Representations 
of energy efficiency ratio 2 (EER2) and IVHEC may 
optionally be made. Representations of coefficient of performance 2 
(COP2) at 5 [deg]F, 17 [deg]F, and 47 [deg]F may optionally be made.
    Sections 3 and 4 of this appendix provide additional 
instructions for testing. In cases where there is a conflict, the 
language of this appendix takes highest precedence, followed by AHRI 
1340-2023, followed by ANSI/ASHRAE 37-2009. Any subsequent amendment 
to a referenced document by the standard-setting organization will 
not affect the test procedure in this appendix, unless and until the 
test procedure is amended by DOE.

3. Test Conditions

    The following conditions specified in AHRI 1340-2023 apply when 
testing to certify to the energy conservation standards in Sec.  
431.97. For cooling mode, use the rating conditions in Table 7 of 
AHRI 1340-2023. For heat pump heating mode tests, use the rating 
conditions in Table 23 of AHRI 1340-2023 and the IVHE building load 
profile in Table 22 of AHRI 1340-2023.
    Representations of EER2 made using the ``Cooling Bin A'' 
conditions in Table 7 of AHRI 1340-2023 are optional. 
Representations of IVHEC made using the IVHEC 
Cold Climate building load profile in Table 22 of AHRI 1340-2023 are 
optional. Representations of COP247, COP217, 
and COP25 are optional.

4. Tower Fan and Pump Power Rate (TFPPR)

    Where equations 8, 10, 11, and 13 to AHRI 1340-2023 call for 
using the cooling tower fan and condenser water pump power rate 
(TFPPR) for the cooling bin specified in Table 7 to AHRI 1340-2023, 
instead use the TFPPR value for the cooling bin specified in table 1 
to this appendix. Where equation 22 to AHRI 1340-2023 calls for 
using a value of 0.0094 W/(Btu/h) for TFPPR, instead use a value of 
0.0102 W/(Btu/h).

[[Page 44048]]



                                     Table 1--Tower Fan and Pump Power Rate
                                                     [TFPPR]
----------------------------------------------------------------------------------------------------------------
                 Cooling bin                   Cooling Bin A    Cooling Bin B    Cooling Bin C    Cooling Bin D
----------------------------------------------------------------------------------------------------------------
Tower Fan and Pump Power Rate (TFPPR), W/             0.0102           0.0099           0.0121           0.0430
 (Btu/h)....................................
----------------------------------------------------------------------------------------------------------------

5. Additional Heating Operating Level Provisions

5.1. Boost2 Heating Operating Level Definition

    In place of the boost2 heating operating level definition in 
section 3.2.31.2 of AHRI 1340-2023, use the following definition: An 
operating level allowed by the controls at 5.0 [deg]F outdoor dry-
bulb temperature with a capacity at 5.0 [deg]F outdoor dry-bulb 
temperature that is less than or equal to the maximum capacity 
allowed by the controls at 5.0 [deg]F outdoor dry-bulb temperature 
and greater than the capacity of:
    (a) The boost heating operating level at 5.0 [deg]F outdoor dry-
bulb temperature, if there is an operating level that meets the 
definition for boost heating operating level specified in section 
3.2.31.1 of AHRI 1340-2023; or
    (b) The high heating operating level at 5.0 [deg]F outdoor dry-
bulb temperature, if there is not an operating level that meets the 
definition for boost heating operating level specified in section 
3.2.31.1 of AHRI 1340-2023.

5.2. Requirements for H5B2 Test in Table 23 to AHRI 1340-2023

    In place of the third to last paragraph of section 6.3.6 of AHRI 
1340-2023, use the following provisions.
    Run the H5B2 test in Table 23 of AHRI 1340-2023 only if there is 
an operating level allowed by the controls at 5.0 [deg]F that meets 
the definition of the boost2 heating operating level specified in 
section 5.1 of this appendix, and the H5B2 test is being used to 
determine the capacity at 5.0 [deg]F outdoor dry-bulb temperature 
and/or COP25.
    If the unit has a boost heating operating level, run the H5B2 
test in Table 23 of AHRI 1340-2023 with an operating level allowed 
by the controls at 5.0 [deg]F outdoor dry-bulb temperature that has 
a capacity at 5.0 [deg]F outdoor dry-bulb temperature that is 
greater than the capacity of the boost heating operating level at 
5.0 [deg]F outdoor dry-bulb temperature and less than or equal to 
the maximum capacity allowed by the controls at 5.0 [deg]F outdoor 
dry-bulb temperature.
    If the unit does not have a boost heating operating level, run 
the H5B2 test in Table 23 of AHRI 1340-2023 with an operating level 
allowed by the controls at 5.0 [deg]F outdoor dry-bulb temperature 
that has a capacity at 5.0 [deg]F outdoor dry-bulb temperature that 
is greater than the capacity of the high heating operating level at 
5.0 [deg]F outdoor dry-bulb temperature and less than or equal to 
the maximum capacity allowed by the controls at 5.0 [deg]F outdoor 
dry-bulb temperature. Use the indoor airflow that is used by the 
controls at 5.0 [deg]F outdoor dry-bulb temperature when operating 
at the chosen operating level.
    The H5B2 test shall not be used in the calculation of IVHE or 
IVHEC.

5.3. Operating Level Requirements for COP2

    Any references to COP2H in AHRI 1340-2023 shall be 
considered synonymous with COP2 as defined in Sec.  431.92. In place 
of section 6.3.14.2 of AHRI 1340-2023, use the following provisions.
    To determine COP247, use capacity and power 
determined for the H47H test.
    To determine COP217, the following provisions apply. 
For units without a boost heating operating level, use capacity and 
power determined for the H17H test. For units with a boost operating 
level, use capacity and power determined for the H17B test.
    To determine COP25, the following provisions apply. 
For units without a boost heating operating level and without a 
boost2 heating operating level, use capacity and power determined 
for the H5H test. For units with a boost heating operating level and 
without a boost2 heating operating level, use capacity and power 
determined for the H5B test. For units with a boost2 heating 
operating level, use capacity and power determined for the H5B2 
test.

6. Set-Up and Test Provisions for Specific Components

    When testing equipment that includes any of the features listed 
in table 2 to this appendix, test in accordance with the set-up and 
test provisions specified in table 2.

            Table 2--Test Provisions for Specific Components
------------------------------------------------------------------------
           Component                 Description        Test provisions
------------------------------------------------------------------------
Air Economizers................  An automatic system  For any air
                                  that enables a       economizer that
                                  cooling system to    is factory-
                                  supply outdoor air   installed, place
                                  to reduce or         the economizer in
                                  eliminate the need   the 100% return
                                  for mechanical       position and
                                  cooling during       close and seal
                                  mild or cold         the outside air
                                  weather              dampers for
                                                       testing. For any
                                                       modular air
                                                       economizer
                                                       shipped with the
                                                       unit but not
                                                       factory-
                                                       installed, do not
                                                       install the
                                                       economizer for
                                                       testing.
Barometric Relief Dampers......  An assembly with     For any barometric
                                  dampers and means    relief dampers
                                  to automatically     that are factory-
                                  set the damper       installed, close
                                  position in a        and seal the
                                  closed position      dampers for
                                  and one or more      testing. For any
                                  open positions to    modular
                                  allow venting        barometric relief
                                  directly to the      dampers shipped
                                  outside a portion    with the unit but
                                  of the building      not factory-
                                  air that is          installed, do not
                                  returning to the     install the
                                  unit, rather than    dampers for
                                  allowing it to       testing.
                                  recirculate to the
                                  indoor coil and
                                  back to the
                                  building
Desiccant Dehumidification       An assembly that     Disable desiccant
 Components.                      reduces the          dehumidification
                                  moisture content     components for
                                  of the supply air    testing.
                                  through moisture
                                  transfer with
                                  solid or liquid
                                  desiccants
Drain Pan Heaters..............  A heater that heats  Disconnect drain
                                  the drain pan to     pan heaters for
                                  make certain that    testing.
                                  water shed from
                                  the outdoor coil
                                  during a defrost
                                  does not freeze
Evaporative Pre-cooling of Air-  Water is evaporated  Disconnect the
 cooled Condenser Intake Air.     into the air         unit from a water
                                  entering the air-    supply for
                                  cooled condenser     testing i.e.,
                                  to lower the dry-    operate without
                                  bulb temperature     active
                                  and thereby          evaporative
                                  increase             cooling.
                                  efficiency of the
                                  refrigeration
                                  cycle

[[Page 44049]]

 
Fire/Smoke/Isolation Dampers...  A damper assembly    For any fire/smoke/
                                  including means to   isolation dampers
                                  open and close the   that are factory-
                                  damper mounted at    installed, set
                                  the supply or        the dampers in
                                  return duct          the fully open
                                  opening of the       position for
                                  equipment            testing. For any
                                                       modular fire/
                                                       smoke/isolation
                                                       dampers shipped
                                                       with the unit but
                                                       not factory-
                                                       installed, do not
                                                       install the
                                                       dampers for
                                                       testing.
Fresh Air Dampers..............  An assembly with     For any fresh air
                                  dampers and means    dampers that are
                                  to set the damper    factory-
                                  position in a        installed, close
                                  closed and one       and seal the
                                  open position to     dampers for
                                  allow air to be      testing. For any
                                  drawn into the       modular fresh air
                                  equipment when the   dampers shipped
                                  indoor fan is        with the unit but
                                  operating            not factory-
                                                       installed, do not
                                                       install the
                                                       dampers for
                                                       testing.
Hail Guards....................  A grille or similar  Remove hail guards
                                  structure mounted    for testing.
                                  to the outside of
                                  the unit covering
                                  the outdoor coil
                                  to protect the
                                  coil from hail,
                                  flying debris and
                                  damage from large
                                  objects
High-Effectiveness Indoor Air    Indoor air filters   Test with the
 Filtration.                      with greater air     standard filter.
                                  filtration
                                  effectiveness than
                                  the filters used
                                  for testing
Power Correction Capacitors....  A capacitor that     Remove power
                                  increases the        correction
                                  power factor         capacitors for
                                  measured at the      testing.
                                  line connection to
                                  the equipment
Process Heat recovery/Reclaim    A heat exchanger     Disconnect the
 Coils/Thermal Storage.           located inside the   heat exchanger
                                  unit that            from its heat
                                  conditions the       source for
                                  equipment's supply   testing.
                                  air using energy
                                  transferred from
                                  an external source
                                  using a vapor,
                                  gas, or liquid
Refrigerant Reheat Coils.......  A heat exchanger     De-activate
                                  located downstream   refrigerant
                                  of the indoor coil   reheat coils for
                                  that heats the       testing so as to
                                  supply air during    provide the
                                  cooling operation    minimum (none if
                                  using high           possible) reheat
                                  pressure             achievable by the
                                  refrigerant in       system controls.
                                  order to increase
                                  the ratio of
                                  moisture removal
                                  to cooling
                                  capacity provided
                                  by the equipment
Steam/Hydronic Heat Coils......  Coils used to        Test with steam/
                                  provide              hydronic heat
                                  supplemental         coils in place
                                  heating              but providing no
                                                       heat.
UV Lights......................  A lighting fixture   Turn off UV lights
                                  and lamp mounted     for testing.
                                  so that it shines
                                  light on the
                                  indoor coil, that
                                  emits ultraviolet
                                  light to inhibit
                                  growth of
                                  organisms on the
                                  indoor coil
                                  surfaces, the
                                  condensate drip
                                  pan, and/other
                                  locations within
                                  the equipment
Ventilation Energy Recovery      An assembly that     For any VERS that
 System (VERS).                   preconditions        is factory-
                                  outdoor air          installed, place
                                  entering the         the VERS in the
                                  equipment through    100% return
                                  direct or indirect   position and
                                  thermal and/or       close and seal
                                  moisture exchange    the outside air
                                  with the exhaust     dampers and
                                  air, which is        exhaust air
                                  defined as the       dampers for
                                  building air being   testing, and do
                                  exhausted to the     not energize any
                                  outside from the     VERS
                                  equipment            subcomponents
                                                       (e.g., energy
                                                       recovery wheel
                                                       motors). For any
                                                       VERS module
                                                       shipped with the
                                                       unit but not
                                                       factory-
                                                       installed, do not
                                                       install the VERS
                                                       for testing.
------------------------------------------------------------------------

[FR Doc. 2024-08543 Filed 5-17-24; 8:45 am]
BILLING CODE 6450-01-P