[Federal Register Volume 87, Number 205 (Tuesday, October 25, 2022)]
[Rules and Regulations]
[Pages 64550-64607]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-22257]



[[Page 64549]]

Vol. 87

Tuesday,

No. 205

October 25, 2022

Part II





Department of Energy





-----------------------------------------------------------------------





10 CFR Parts 429 and 430





Energy Conservation Program: Test Procedure for Central Air 
Conditioners and Heat Pumps; Final Rule

  Federal Register / Vol. 87 , No. 205 / Tuesday, October 25, 2022 / 
Rules and Regulations  

[[Page 64550]]


-----------------------------------------------------------------------

DEPARTMENT OF ENERGY

10 CFR Parts 429 and 430

[EERE-2021-BT-TP-0030]
RIN 1904-AF29


Energy Conservation Program: Test Procedure for Central Air 
Conditioners and Heat Pumps

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

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The U.S. Department of Energy (``DOE'') is amending the test 
procedures for central air conditioners and heat pumps that will be 
required for certification of compliance with applicable energy 
conservation standards starting January 1, 2023, to address a limited 
number of specific issues, and making minor corrections to the current 
test procedures that are required for certification of compliance with 
applicable energy conservation standards prior to January 1, 2023. This 
rulemaking does not satisfy the 7-year lookback requirement prescribed 
by the Energy Policy and Conservation Act (``EPCA'').

DATES: The effective date of this rule is November 25, 2022. The final 
rule changes will be mandatory for product testing starting April 24, 
2023. The incorporation by reference of a certain publication listed in 
the rule was approved by the Director of the Federal Register on 
February 6, 2017.

ADDRESSES: The docket, which includes Federal Register notices, public 
meeting attendee lists and transcripts, comments, and other supporting 
documents/materials, is available for review at www.regulations.gov. 
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-2021-BT-TP-0030 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. Lucas Adin, 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: 
(202) 287-5904. Email: [email protected].
    Mr. Pete Cochran, U.S. Department of Energy, Office of the General 
Counsel, GC-33, 1000 Independence Avenue SW, Washington, DC 20585-0121. 
Telephone: (202) 586-9496. Email: [email protected].

SUPPLEMENTARY INFORMATION: DOE maintains the following previously 
approved incorporation by reference in part 430:
    ANSI/ASHRAE Standard 37-2009, Methods of Testing for Rating 
Electrically Driven Unitary Air-Conditioning and Heat Pump Equipment, 
ANSI approved June 25, 2009;
    Copies of ANSI/ASHRAE 37-2009, can be purchased from 
www.ashrae.org/resources--publications.
    For a further discussion of this standard, see section IV.M of this 
document.

Table of Contents

I. Authority and Background
    A. Authority
    B. Background
II. Synopsis of the Final Rule
III. Discussion
    A. Scope of Applicability
    B. Requests for Future Test Procedure Revisions
    C. Topics Arising From Test Procedure Waivers
    1. Fan Power at Reduced Airflows for Coil-Only Systems
    2. Variable-Speed Coil-Only Test Procedure
    3. Space-constrained Coil-Only CAC Ratings
    D. Other Test Procedure Revisions
    1. Air Volume Rate Changing With Outdoor Conditions
    2. Wet Bulb Temperature for H4 5 [deg]F Heating Tests
    3. Hierarchy of Manufacturer Installation Instructions
    4. Adjusting Airflow Measurement Apparatus To Achieve Desired 
SCFM at Part-Load Conditions
    5. Revision of Equations Representing Full-Speed Variable-Speed 
Heat Pump Operation at and Above 45 [deg]F Ambient Temperature
    6. Calculations for Triple-Capacity Northern Heat Pumps
    7. Heating Nominal Air Volume Rate for Variable-Speed Heat Pumps
    8. Clarifications for HSPF2 Calculation
    9. Distinguishing Central Air Conditioners and Heat Pumps From 
Commercial Equipment
    10. Additional Test Procedure Revisions
    E. Other Revisions Regarding Representations
    1. Required Represented Values for Models Certified Compliant 
With Regional Standards
    F. Test Procedure Costs and Impact
    G. Compliance Date and Waivers
    H. Requests for Standards Relief
IV. Procedural Issues and Regulatory Review
    A. Review Under Executive Orders 12866 and 13563
    B. Review Under the Regulatory Flexibility Act
    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. Description of Material Incorporated by Reference
    N. Congressional Notification
V. Approval of the Office of the Secretary

I. Authority and Background

    Central air conditioners (``CACs'') and central air conditioning 
heat pumps (``HPs'') (collectively, ``CAC/HPs'') are included in the 
list of ``covered products'' for which DOE is authorized to establish 
and amend energy conservation standards and test procedures (42 U.S.C. 
6292(a)(3)) DOE's energy conservation standards and test procedures for 
CAC/HPs are currently prescribed at title 10 of the Code of Federal 
Regulations (``CFR''), part 430, Sec.  430.32(c), and 10 CFR part 430, 
subpart B, appendices M (``appendix M'') and M1 (``appendix M1''). The 
following sections discuss DOE's authority to establish test procedures 
for CAC/HPs and relevant background information regarding DOE's 
consideration of test procedures for this product.

A. Authority

    The Energy Policy and Conservation Act, as amended (``EPCA''),\1\ 
authorizes DOE to regulate the energy efficiency of a number of 
consumer products and certain industrial equipment. (42 U.S.C. 6291-
6317) Title III, Part B \2\ of EPCA established the Energy Conservation 
Program for Consumer Products Other Than Automobiles, which sets forth 
a variety of provisions designed to improve energy efficiency. These

[[Page 64551]]

products include CAC/HPs,\3\ the subject of this document. (42 U.S.C. 
6292(a)(3))
---------------------------------------------------------------------------

    \1\ 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).
    \2\ For editorial reasons, upon codification in the U.S. Code, 
Part B was redesignated Part A.
    \3\ This rulemaking uses the term ``CAC/HP'' to refer 
specifically to central air conditioners (which include heat pumps) 
as defined by EPCA. (42 U.S.C. 6291(21))
---------------------------------------------------------------------------

    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 specifically include definitions (42 U.S.C. 6291), 
test procedures (42 U.S.C. 6293), labeling provisions (42 U.S.C. 6294), 
energy conservation standards (42 U.S.C. 6295), and the authority to 
require information and reports from manufacturers (42 U.S.C. 6296).
    The Federal testing requirements consist of test procedures that 
manufacturers of covered products must use as the basis for: (1) 
certifying to DOE that their products comply with the applicable energy 
conservation standards adopted pursuant to EPCA (42 U.S.C. 6295(s)), 
and (2) making representations about the efficiency of those consumer 
products (42 U.S.C. 6293(c)). Similarly, DOE must use these test 
procedures to determine whether the products comply with relevant 
standards promulgated under EPCA. (42 U.S.C. 6295(s))
    Federal energy efficiency requirements for covered products 
established under EPCA generally supersede State laws and regulations 
concerning energy conservation testing, labeling, and standards. (42 
U.S.C. 6297) DOE may, however, grant waivers of Federal preemption for 
particular State laws or regulations, in accordance with the procedures 
and other provisions of EPCA. (42 U.S.C. 6297(d))
    Under 42 U.S.C. 6293, EPCA sets forth the criteria and procedures 
DOE must follow when prescribing or amending test procedures for 
covered products. EPCA requires that any test procedures prescribed or 
amended under this section be reasonably designed to produce test 
results which measure energy efficiency, energy use or estimated annual 
operating cost of a covered product during a representative average use 
cycle or period of use and not be unduly burdensome to conduct. (42 
U.S.C. 6293(b)(3))
    If the Secretary determines, on her own behalf or in response to a 
petition by any interested person, that a test procedure should be 
prescribed or amended, the Secretary shall promptly publish in the 
Federal Register proposed test procedures and afford interested persons 
an opportunity to present oral and written data, views, and arguments 
with respect to such procedures. (42 U.S.C. 6293(b)(2)) The comment 
period on a proposed rule to amend a test procedure shall be at least 
60 days and may not exceed 270 days. Id. In prescribing or amending a 
test procedure, the Secretary shall take into account such information 
as the Secretary determines relevant to such procedure, including 
technological developments relating to energy use or energy efficiency 
of the type (or class) of covered products involved. Id.
    DOE's regulations at 10 CFR 430.27 provide that any interested 
person may seek a waiver from the test procedure requirements if 
certain conditions are met. A waiver requires manufacturers to use an 
alternate test procedure in situations in which the DOE test procedure 
cannot be used to test the product or equipment, or use of the DOE test 
procedure would generate unrepresentative results. 10 CFR 430.27(a)(1). 
DOE's regulations at 10 CFR 430.27(l) require that as soon as 
practicable after the granting of any waiver, DOE will publish in the 
Federal Register a notice of proposed rulemaking (``NOPR'') to amend 
its regulations so as to eliminate any need for the continuation of 
such waiver. As soon thereafter as practicable, DOE will publish in the 
Federal Register a final rule. 10 CFR 430.27(l).
    DOE is publishing this final rule for the limited purpose of 
addressing its obligations under the waiver process regulations at 10 
CFR 430.27 and to incorporate additional corrections and improvements.

B. Background

    As discussed, DOE's existing test procedures for CAC/HPs appear at 
appendices M and M1 (both titled ``Uniform Test Method for Measuring 
the Energy Consumption of Central Air Conditioners and Heat Pumps'').
    On January 5, 2017, DOE published a final rule regarding the 
Federal test procedure (``TP'') for CAC/HPs. 82 FR 1426 (``January 2017 
CAC TP Final Rule''). The January 2017 CAC TP Final Rule amended 
appendix M and established appendix M1, use of which is required 
beginning January 1, 2023, for any representations, including 
compliance certifications, made with respect to the energy use or 
efficiency of CAC/HPs. Id. Appendix M provides for the measurement of 
the cooling and heating performance of CAC/HPs using the seasonal 
energy efficiency ratio (``SEER'') metric and heating seasonal 
performance factor (``HSPF'') metric, respectively. Appendix M1 
specifies a revised SEER metric (i.e., SEER2) and a revised HSPF metric 
(``HSPF2'').
    Since the publication of the January 2017 CAC TP Final Rule, DOE 
has granted various petitions for waiver and interim waiver from 
certain provisions of appendix M and/or M1.\4\ Additionally, DOE is 
aware of testing conducted per both appendices M (via Compliance, 
Certification and Enforcement (``CCE'') testing and other verification 
programs) and M1 (via investigative testing to support development of 
the 2023 energy efficiency standards). Through these efforts, DOE has 
been made aware of several items for which test procedure amendments 
are warranted in order to improve clarity or to reduce burden. In each 
of these cases, DOE has determined that the amendments would have no or 
negligible impact on ratings and thus do not require amendment of the 
energy conservation standards per 42 U.S.C. 6293(e). These amendments 
are described in section III.D of this final rule. Further, on May 8, 
2019, AHRI submitted a comment responding to the notice of proposed 
rulemaking to revise and adopt procedures, interpretations, and 
policies for consideration of new or revised energy conservation 
standards (2020 Process Rule NOPR, 84 FR 3910, Feb. 13, 2019) The 
comment included as Exhibit 2 a ``List of Errors Found in both appendix 
M and appendix M1'' (``AHRI Exhibit 2,'' EERE-2017-BT-STD-0062-0117 at 
pp. 23-24). Many of the errors pointed out by AHRI regard typographical 
errors in appendices M and M1. These issues are addressed in various 
places of this final rule, including footnotes describing amendments to 
correct section references, nomenclature, etc. that did not warrant 
standalone discussion sections.
---------------------------------------------------------------------------

    \4\ Waivers granted to GD Midea Heating and Ventilating 
Equipment Co., Ltd. (83 FR 56065), Johnson Controls, Inc. (83 FR 
12735 and 84 FR 52489), and TCL Air Conditioner (Zhongshan) Co., 
Ltd. (84 FR 11941), interim waivers granted to National Comfort 
Products, Inc. (83 FR 24754), Aerosys Inc. (83 FR 24762), LG 
Electronics U.S.A., Inc. (85 FR 40272), and Goodman Manufacturing 
Company, L.P. (86 FR 40534).
---------------------------------------------------------------------------

    On March 24, 2022, DOE published a notice of proposed rulemaking 
regarding the Federal test procedure for CAC/HPs. 87 FR 16830 (``March 
2022 CAC TP NOPR''). The March 2022 CAC TP NOPR proposed changes to 
improve the functionality of appendix M1 to address the issues 
identified in test procedure waivers, improve representativeness and 
correct typographical issues raised by commenters. Id. DOE held a 
public meeting related to the NOPR on April

[[Page 64552]]

18, 2022 (hereafter the ``2022 CAC TP NOPR Public Meeting'').
    DOE received comments in response to the March 2022 CAC TP NOPR 
from the interested parties listed in Table I-1.

        Table I-1--List of Commenters With Written Submissions in Response to the March 2022 CAC TP NOPR
----------------------------------------------------------------------------------------------------------------
                                            Reference in this final   Comment No. in
              Commenter(s)                           rule               the docket          Commenter type
----------------------------------------------------------------------------------------------------------------
Air-Conditioning, Heating, &              AHRI......................              25  Trade Association.
 Refrigeration Institute.
Appliance Standards Awareness Project     Joint Advocates...........              18  Efficiency organizations.
 (ASAP), American Council for an Energy-
 Efficient Economy (ACEEE).
Pacific Gas and Electric Company, San     CA IOUs...................              20  Efficiency organization.
 Diego Gas and Electric, Southern
 California Edison--collectively
 California Investor Owned Utilities.
Carrier Global Corporation..............  Carrier...................              15  Manufacturer.
Daikin Comfort Technologies               Daikin....................              24  Manufacturer.
 Manufacturing Company, L.P.
Emerson Climate Technologies, Inc.......  Emerson...................              14  Manufacturer.
Leaders Building of America.............  LBA.......................               3  Trade Association.
Lennox International Inc................  Lennox....................              19  Manufacturer.
National Comfort Products, Inc..........  NCP.......................              16  Manufacturer.
Northwest Energy Efficiency Alliance....  NEEA......................              23  Alliance of Efficiency
                                                                                       Organizations.
Nortek Global HVAC (NGH)................  Nortek....................              13  Manufacturer.
New York State Energy Research and        NYSERDA...................              17  Efficiency organization.
 Development Authority.
Rheem Sales Company.....................  Rheem.....................              21  Manufacturer.
Samsung HVAC............................  Samsung...................              22  Manufacturer.
Trane Technologies......................  Trane.....................              10  Manufacturer.
----------------------------------------------------------------------------------------------------------------

    A parenthetical reference at the end of a comment quotation or 
paraphrase provides the location of the item in the public record.\5\
---------------------------------------------------------------------------

    \5\ The parenthetical reference provides a reference for 
information located in the docket of DOE's rulemaking to develop 
test procedures for central air conditioners and heat pumps (Docket 
No. EERE-2021-BT-TP-0030, which is maintained at 
www.regulations.gov). The references are arranged as follows: 
(commenter name, comment docket ID number, page of that document).
---------------------------------------------------------------------------

    The CA IOUs, Carrier, Daikin, Emerson, Joint Advocates, Lennox, 
NEEA, Nortek, NYSERDA, and Rheem commented that they largely supported 
DOE's efforts in amending the existing test procedure in appendix M1. 
(CA IOUs, No. 20 at p. 3, Carrier, No. 20 at p. 1, Daikin, No. 24 at p. 
1, Emerson, No. 14 at p. 1, Joint Advocates, No. 18 at p. 1, Lennox, 
No. 19 at p. 1, NEEA, No. 23 at p. 1, Nortek, No. 13 at p. 1, NYSERDA, 
No. 17 at p. 1, Rheem, No. 21 at p. 1) Emerson requested that DOE 
publish the revised test procedure as soon as reasonably possible, so 
that manufacturers will have time to comply with the compliance date of 
January 1, 2023. (Emerson, No. 14 at p. 3) Nortek also requested that 
DOE publish the final rule soon, so that they can have certainty with 
the revised test procedure, in order to serve the CAC/HP market 
efficiently. (Nortek, No. 13 at p. 3)

II. Synopsis of the Final Rule

    In this final rule, DOE is updating appendix M1 to subpart B of 
part 430, ``Uniform Test Method for Measuring the Energy Consumption of 
Central Air Conditioners and Heat Pumps.'' DOE has identified certain 
provisions of appendix M1 that may benefit from additional detail and/
or instruction. The updates are as follows:
    (1) Adjusting the default fan power for two-stage coil-only systems 
when testing at low stage with reduced air volume rate to be more 
representative of fan input power trends as air volume rate reduces;
    (2) Defining ``variable-speed communicating coil-only central air 
conditioner or heat pump'' and ``variable-speed non-communicating coil-
only central air conditioner or heat pump'' and establishing procedures 
specific for testing such systems;
    (3) Allowing the adjustment of the air volume rate as a function of 
outdoor air temperature during testing for blower coil systems with 
either multiple-speed or variable-speed indoor fans and with a control 
system capable of adjusting air volume rate as function of outdoor air 
temperature;
    (4) Adjusting the maximum wet bulb temperature from 3 [deg]F to 4 
[deg]F for the H4 test condition;
    (5) Specifying in section 2(B) of appendix M1, that the 
instructions presented in the labels attached to the unit take 
precedence over the installation manuals printed and shipped with a 
product;
    (6) Specifying in sections 3.1.4.1.1, 3.1.4.1.2, and 3.1.4.4.3 of 
appendix M1 that the airflow measurement apparatus fan must be adjusted 
if necessary to maintain the same air volume rate for different test 
conditions for systems not including multiple-speed or variable-speed 
indoor fans with control system capability to adjust air volume rate as 
function of operating conditions such as outdoor air temperature; and
    (7) Revising the equations representing full-capacity operation of 
variable-speed heat pumps at and above 45 [deg]F ambient temperature to 
be consistent with the intent for nominal capacity operation.
    Additionally, in this final rule, DOE is updating 10 CFR part 429, 
``Certification, Compliance, and Enforcement for Consumer Products and 
Commercial and Industrial Equipment.'' DOE has identified certain 
provisions of part 429 that may benefit from additional detail and/or 
instruction. The proposed updates are as follows:
    (1) Clarifying the language for required represented values for 
single-stage and two-stage coil-only CACs; and
    (2) Providing additional direction regarding the regional standard 
requirements in part 429.
    The adopted amendments are summarized in Table II-1 compared to the 
test procedure provision prior to the amendment, as well as the reason 
for the adopted change. Additional proposed incidental changes are 
summarized in Table III-4, Table III-5 and Table III-6 in section 
III.D.10 of this document.

[[Page 64553]]



                          Table II-1--Summary of Changes in the Amended Test Procedure
----------------------------------------------------------------------------------------------------------------
   DOE test procedure prior to amendment              Amended test procedure                   Attribution
----------------------------------------------------------------------------------------------------------------
Calculate indoor fan power of two-stage     Calculate indoor fan power of two-stage     Improve
 coil-only CACs and HPs using constant       coil-only CACs and HPs for reduced air      representativeness.
 default fan power values that do not vary   volume rate tests using new default fan
 with air volume rate (441W/1000 scfm for    power values air volume rate (335 W/1000
 most two-stage coil-only CACs and HPs and   scfm for most two-stage coil-only CACs
 406 W/1000 scfm for mobile-home and space-  and HPs and 308 W/1000 scfm for mobile-
 constrained CACs and HPs).                  home and space-constrained CACs and HPs).
                                             Use linear interpolation to determine fan
                                             performance at intermediate airflow rates
                                             between 75 percent and 100 percent of
                                             full-load air volume rate.
No test procedure provisions for variable-  Test procedures and requirements            Incorporate test
 speed, coil-only CACs and HPs.              established for variable-speed coil-only    procedures contained in
                                             systems, include new definitions for        test procedure waivers.
                                             ``variable-speed communicating coil-only
                                             central air conditioner or heat pump''
                                             and ``variable-speed non-communicating
                                             coil-only central air conditioner or heat
                                             pump,'' for which the newly established
                                             test procedures have more flexibility.
Appendix M1 currently does not explicitly   For blower coil systems with multiple-      Improve
 allow for variation of air volume rate as   speed or variable-speed indoor fans and     representativeness for
 outdoor temperature changes when testing    the control system capability to adjust     certain models.
 blower coil systems.                        air volume rate as a function of outdoor
                                             air temperature, allow such air volume
                                             rate variation during testing.
Appendix M1 contains provisions for         Amend the wet bulb test condition for the   Reduce test burden by
 conducting an optional H4 heating test at   H4 test to be 4 [deg]F maximum instead of   reducing the time
 a 5 [deg]F outdoor ambient dry-bulb         the current condition of 3 [deg]F           needed to remove
 temperature and, at a maximum, a 3 [deg]F   maximum.                                    sufficient moisture to
 outdoor wet-bulb temperature.                                                           achieve the wet bulb
                                                                                         requirement.
Clarification regarding which form of       Add direction to prioritize the             Improve
 installation instructions to use, if        instructions presented in the label         representativeness and
 multiple forms are provided, only for       attached to the unit over the               repeatability.
 variable refrigerant flow (VRF)             installation instructions shipped with
 multisplit systems.                         the unit for all CAC/HP products.
Appendix M1 currently is not clear about    Add specific instruction to adjust the      Improve
 how to achieve the same air volume rate     airflow measurement apparatus fan but not   representativeness and
 for different test conditions.              the fan of the unit under test to achieve   repeatability.
                                             the same air volume rate for different
                                             tests.
The equations for full-capacity operation   Revise the equations for full-capacity      Improve
 for variable-speed heat pumps at and        operation at and above 45 [deg]F to be      representativeness.
 above 45 [deg]F ambient temperature are     more consistent with compressor speed
 based on operating in this range with a     used in normal operation for this
 compressor speed the same as its            temperature range, represented by the
 operation in 17 [deg]F ambient              nominal heating test condition, H1N.
 temperature.
10 CFR part 429 provides requirements       Reinforce the language explaining regional  Improve clarity.
 regarding regional CAC/HP efficiency        requirements.
 standards.
10 CFR 429.16(a)(1) provides requirements   Modify the instructions in that section to  Improve repeatability.
 for represented values of single-stage      improve clarity without changing meaning.
 and two-stage coil-only CACs that can
 lead to different interpretation.
10 CFR 430.2 defines central air            Add exclusions for additional commercial    Improved
 conditioner, excluding two commercial       package air-conditioning and heating        representativeness.
 package air-conditioning and heating        categories that justifiably are not
 categories--packaged terminal air           central air conditioners.
 conditioners and packaged terminal heat
 pumps.
----------------------------------------------------------------------------------------------------------------

    As mentioned previously, DOE is also fixing typographical errors in 
appendices M and M1 that were raised by AHRI. (``AHRI Exhibit 2,'' 
EERE-2017-BT-STD-0062-0117 at pp. 23-24) DOE is addressing these issues 
in this rulemaking.
    Under 42 U.S.C. 6293(e)(1), DOE is required to determine whether an 
amended test procedure will alter the measured energy use of any 
covered product. If an amended test procedure does alter measured 
energy use, DOE is required to make a corresponding adjustment to the 
applicable energy conservation standard to ensure that minimally 
compliant covered products remain compliant. (42 U.S.C. 6293(e)(2)) DOE 
has determined that the amendments described in section III of this 
final rule would not alter the measured efficiency of CAC/HPs that are 
rated using the test procedure that is currently required for testing, 
i.e., appendix M. The revisions applicable for appendix M simply fix 
errors within the current test procedure. With respect to appendix M1, 
many of the amendments clarify test procedures rather than making 
changes that would affect the measurements. Variable-speed coil-only 
systems are not addressed currently in the test procedure, so this 
final rule establishes a method of test for those products. For two-
stage coil-only systems, DOE is amending the default fan power 
coefficients and default fan heat coefficients to be more 
representative, as further described in section III.C.1 of this 
document, which DOE believes will slightly improve the measured 
efficiency of these combinations as compared to their current 
representative values. Given that two-stage combinations are not 
representative of minimally compliant combinations, DOE has determined 
that this amendment would not require an

[[Page 64554]]

adjustment to the energy conservation standard for central air 
conditioners and heat pumps to ensure that minimally compliant central 
air conditioners and heat pumps would remain compliant. Additionally, 
DOE has determined that the amendments would not increase the cost of 
testing. Discussion of DOE's actions are addressed in detail in section 
III of this final rule.
    The effective date for the amended test procedures adopted in this 
final rule is 30 days after publication of this document in the Federal 
Register. Representations of energy use or energy efficiency must be 
based on testing in accordance with the amended test procedures 
beginning 180 days after the publication of this final rule.

III. Discussion

A. Scope of Applicability

    DOE is amending the test procedures at appendix M1 for CAC/HP and 
implementing a few minor clerical revisions to the test procedures at 
appendix M. A ``central air conditioner or central air conditioner heat 
pump'' is defined as a product, other than a packaged terminal air 
conditioner or packaged terminal heat pump, which is powered by single 
phase electric current, air cooled, rated below 65,000 British thermal 
units per hour (``Btu/h''), not contained within the same cabinet as a 
furnace, the rated capacity of which is above 225,000 Btu/h, and is a 
heat pump or a cooling unit only. A central air conditioner or central 
air conditioning heat pump may consist of: A single-package unit; an 
outdoor unit and one or more indoor units; an indoor unit only; or an 
outdoor unit with no match. In the case of an indoor unit only or an 
outdoor unit with no match, the unit must be tested and rated as a 
system (combination of both an indoor and an outdoor unit). 10 CFR 
430.2.
    Appendices M and M1 apply to the following CACs/HPs:
     Split-system air conditioners, including single-split, 
multi-head mini-split, multi-split (including VRF), and multi-circuit 
systems;
     Split-system heat pumps, including single-split, multi-
head mini-split, multi-split (including VRF), and multi-circuit 
systems;
     Single-package air conditioners;
     Single-package heat pumps;
     Small-duct, high-velocity systems (including VRF);
     Space-constrained products--air conditioners; and
     Space-constrained products--heat pumps.
    See Section 1.1 of appendices M and M1.
    DOE is not proposing to change the scope of CACs/HPs covered by 
appendices M and M1.

B. Requests for Future Test Procedure Revisions

    DOE has considered whether the current test procedures for 
variable-speed systems generally give manufacturers too much 
flexibility in specifying fixed settings of the compressor and indoor 
fan for testing without requiring the selected settings to be 
demonstrated using native control testing. DOE is aware that there is 
ongoing work addressing questions about whether the current DOE test 
procedure for variable-speed systems is fully representative of native 
control operation.\6\ However, DOE has initiated this rulemaking not as 
a comprehensive revision that will satisfy the 7-year lookback 
requirements (see 42 U.S.C. 6293(b)(1)(A)), but instead as an action 
that will address a focused group of known issues, including those that 
have been raised through the test procedure waiver process. Thus, DOE 
limited its amendments addressing potential concerns about variable-
speed systems to coil-only systems, for which there are clear 
differences in system controls architecture that impact the performance 
of these systems in the field, particularly when using non-
communicating controls. However, DOE may more comprehensively address 
these issues for all variable-speed systems in a future rulemaking.
---------------------------------------------------------------------------

    \6\ E.g., The German energy regulatory body, Bunderstalt 
f[uuml]r Materialforschung und-Pr[uuml]fung (``BAM''), has developed 
a dynamic load compensation method, to be used as an alternative to 
EN 14825:2016 ``Air conditioners, liquid chilling packages and heat 
pumps, with electrically driven compressors, for space heating and 
cooling. Testing and rating at part load conditions and calculation 
of seasonal performance''. Additionally, the Canadian Standards 
Association (``CSA'') has published the first draft edition of 
CSA:EXP07:19 ``Load-based and climate-specific testing and rating 
procedures for heat pumps and air conditioners'' (``EXP07'').
---------------------------------------------------------------------------

    The CA IOUs, Joint Advocates, NEEA, and NYSERDA all encouraged DOE 
to review ways to improve the representativeness of the test procedures 
for CAC/HP in a future rulemaking under DOE's 7-year lookback 
authority. Specifically, the CA IOUs, Joint Advocates, and NEEA all 
requested that DOE explore approaches that would capture the 
performance of variable-speed and multi-stage systems operating under 
native controls rather than under fixed compressor and fan speed 
controls. (CA IOUs, No.20 at pp.2-3; Joint Advocates, No.18 at p.1; 
NEEA, No.23 at p.1)
    The CA IOUs contended that the current test procedure does not 
fully reflect energy use during the shoulder-season hours when outdoor 
temperatures are typically between 55 [deg]F and 64 [deg]F and the 
equipment is likely in fan-only mode (i.e., the compressor is not 
running). (CA IOUs, No.20 at pp.2-3) DOE acknowledges the CA IOUs' 
comment that shoulder-season fan energy consumption is not captured by 
either the SEER/SEER2 or HSPF/HSPF2 metrics, which are constructed to 
represent the cooling season efficiency and heating season efficiency, 
respectively. However, as previously mentioned, DOE is only planning to 
address a focused group of known issues in this rulemaking and will 
evaluate and addresses a broader set of changes in a future rulemaking. 
The CA IOUs acknowledged this point in their comment, by suggesting 
that DOE consider fan-only energy use during the shoulder-season in a 
subsequent review of the CAC/HP test procedure. Id. Therefore, DOE will 
not adopt any amendments in this rulemaking related to shoulder-season 
energy consumption, as suggested by the CA IOUs.
    The CA IOUs also suggested that DOE consider approaches in a future 
rulemaking to incorporate the power consumption of auxiliary components 
like fans and crankcase heaters operating when the compressor is off. 
(CA IOUs, No.20 at pp.2-3) DOE notes that there are already test 
procedures and energy conservation standards governing the allowable 
off-mode power consumption for CACs and HPs, which encapsulates the 
off-mode and standby power consumed by auxiliary components such as 
crankcase heaters as suggested by the CA IOUs. These test procedures 
are enumerated in section 4.3 of appendices M and M1, and standards are 
enumerated at 10 CFR 430.32(c)(4).
    The CA IOUs further requested that DOE amend the definition of 
``variable-speed compressor systems'' to incorporate CAC/HPs with at 
least three compressor capacity stages that do not meet the definitions 
of VRF or triple-capacity northern heat pumps. Specifically, the CA 
IOUs suggested the following definition (additions in italics):
    Variable-speed compressor system means ``a central air conditioner 
or heat pump that has a compressor that uses a variable-speed drive to 
vary the compressor speed to achieve variable capacities or a 
compressor with at least three compressor capacity stages not including 
triple-capacity northern heat pumps.'' (CA IOUs, No.20 at p.2)
    Section 1.2 of appendix M1 defines ``variable-speed compressor 
systems'' as those CAC/HPs that have ``a compressor

[[Page 64555]]

that uses a variable-speed drive to vary the compressor speed to 
achieve variable capacities.'' The definition for ``variable 
refrigerant flow (VRF) systems'' includes the language ``multi-split 
system with at least three compressor capacity stages, distributing 
refrigerant through a piping network to multiple indoor blower coil 
units.'' The definition for ``triple-capacity, northern heat pump'' in 
appendix M1 includes ``a heat pump that provides two stages of cooling 
and three stages of heating.'' DOE agrees with the CA IOUs' assertion 
that as currently structured, the definitions in appendix M1 do not 
explicitly clarify coverage for the specific case of CAC/HP systems 
having three or more stages (but without a variable-speed drive), do 
not include multiple indoor units (which would meet the definition for 
VRF), and are not heat pumps that include two cooling stages and three 
heating stages (which would meet the definition for triple-capacity 
northern heat pump). However, DOE is not aware of, nor did the CA IOUs 
identify, the existence of such systems. Also, as previously mentioned, 
DOE is only planning to address a focused group of known issues in this 
rulemaking and will evaluate and addresses a broader set of changes in 
future rulemaking. Therefore, DOE will not adopt the revised definition 
of ``variable-speed compressor systems,'' as suggested by the CA IOUs 
in this rulemaking. DOE may consider changes to the definition of 
``variable-speed compressor system'' in a future rulemaking, if 
provided additional evidence of systems existing that meet the criteria 
of the hypothetical system described by the CA IOUs.
    NEEA and the Joint Advocates recommended that DOE adopt a test 
procedure that evaluates performance under loads that respond to the 
heat pump's internal firmware. (NEEA, No.23 at p.1; Joint Advocates, 
No.18 at pp. 3-4) NEEA provided data to support their claim that 
seasonal efficiency performance is highly dependent on the installed 
firmware of the system. Id. at pp.3-4. NEEA compiled this information 
in a report \7\ that was also cited by the Joint Advocates in their 
comment. (Joint Advocates, No.18 at p.4)
---------------------------------------------------------------------------

    \7\ NEEA report ``Heat Pump and Air Conditioner Efficiency 
Ratings: Why Metrics Matter'' available online at: https://neea.org/resources/heat-pump-and-air-conditioner-efficiency-ratings-why-metrics-matter.
---------------------------------------------------------------------------

    NEEA also requested that DOE adopt a load-based test procedure with 
the tested system operating under native controls. (NEEA, No.23 at p.2) 
NEEA again provided data concerning the representativeness of the 
existing DOE test procedure as compared to field data. NEEA cited 
several ongoing projects related to evaluation of load-based testing of 
CAC/HP and recommended that DOE leverage this work as a part of the 
next CAC/HP test procedure rulemaking. Id. at pp.5-7. NEEA additionally 
requested that DOE consider increasing the amount of data reported for 
heat pumps operating at pert-load heating conditions, specifically 
advocating for required reporting of COP for low-compressor-stage tests 
at 67 [deg]F and 47 [deg]F. Id. at p.7.
    NYSERDA encouraged DOE to start immediately on foundational work 
needed to improve the standard and test procedure to better account for 
equipment performance in cold climates. NYSERDA requested that DOE make 
the H4, H42, or H43 heating tests mandatory in 
order to produce more representative ratings that account for system 
performance at 5 [deg]F. NYSERDA also requested that DOE explore how to 
test and report relative capacity maintenance at temperatures lower 
than the heating mode test temperatures that are used to determine 
nominal capacity and suggested that DOE prescribe performance 
requirements of low-temperature capacity maintenance for products 
advertised as cold-climate heat pumps.\8\ Further, NYSERDA requested 
that DOE evaluate how a variety of sizing approaches could be 
incorporated into the test procedure. NYSERDA highlighted that DOE has 
previously established that the sizing assumptions inherent in the DOE 
test procedure are based on cooling capacity and provided an example of 
a sizing and selection guide that emphasizes heating function.\9\ 
NYSERDA ultimately acknowledged that DOE is addressing a more limited 
set of issues in this rulemaking and suggested that if their comments 
could not be considered now, they should be considered applicable for 
the next test procedure update for CACs or other HVAC equipment, as 
appropriate. (NYSERDA, No.17 at pp.2-3)
---------------------------------------------------------------------------

    \8\ NYSERDA cited the EPA's Energy Star Version 6.1 CAC/HP 
specification, which prescribes a heating capacity maintenance of 
70% at 5 [deg]F relative to 47 [deg]F for cold-climate heat pumps. 
The Energy Star specification can be found online at: https://www.energystar.gov/sites/default/files/ENERGY%20STAR%20Central%20Air%20Conditioner%20and%20Heat%20Pump%20Version%206.1%20Final%20Specification.pdf.
    \9\ NYSERDA identified NEEP's ASHP sizing and selection guide, 
available online at: https://neep.org/sites/default/files/resources/ASHP%20Sizing%20%26%20Selecting%20-%208x11_edits.pdf.
---------------------------------------------------------------------------

    In summary, DOE received a variety of comments that requested 
changes to the CAC test procedure beyond the limited scope of proposals 
in the March 2022 CAC TP NOPR. DOE received comments recommending 
consideration of load-based testing methods, controls validation 
(particularly for variable-speed systems), amended metrics, amended 
definitions, and expansion of test methods to capture low-temperature 
heating performance for heat pumps. As stated, DOE will consider these 
comments when conducting the next rulemaking that includes a full 
review of the CAC test procedure.

C. Topics Arising From Test Procedure Waivers

1. Fan Power at Reduced Airflows for Coil-Only Systems
a. Background
    Coil-only air conditioners are matched split-systems consisting of 
a condensing unit and indoor coil that are distributed in commerce 
without an indoor blower or separate designated air mover. Such systems 
installed in the field rely on a separately installed furnace or a 
modular blower for indoor air movement. Because coil-only CAC/HPs do 
not include their own indoor fan to circulate air, the DOE test 
procedures prescribe equations that are used to calculate the assumed 
(i.e., ``default'') power input and heat output of an average furnace 
fan with which the test procedure assumes the indoor coil is pared in a 
field installation. In each equation, the measured airflow rate (in 
cubic feet per minute of standard air (``scfm'')) is multiplied by a 
defined coefficient (expressed in Watts (``W'') per 1,000 scfm (``W/
1000 scfm'') for fan power, and British Thermal Units (``Btu'') per 
hour (``Btu/h'') per 1000 scfm (``Btu/h/1000 scfm'') for fan heat), 
hereafter referred to as the ``default fan power coefficient'' and 
``default fan heat coefficient.'' The resulting fan power input value 
is added to the electrical power consumption measured during testing. 
The resulting fan heat output value is subtracted from the measured 
cooling capacity of the CAC/HP for cooling mode tests and added to the 
measured heating capacity for heating mode tests.
    In appendix M1, separate fan power and fan heat equations are 
provided for different types of coil-only systems (i.e., the equations 
for mobile home or space-constrained are different than for 
``conventional'' non-mobile home and non-space-constrained).\10\ 10 CFR 
part

[[Page 64556]]

430, subpart B, appendix M1, see, e.g., section 3.3. For coil-only 
units installed in mobile-homes and for space-constrained systems, 
appendix M1 defines a default fan power coefficient of 406 W/1000scfm 
and a default fan heat coefficient of 1,385 Btu/h/1000 scfm. See, e.g., 
appendix M1, section 3.3.d. For coil-only units installed in 
conventional (i.e., non-mobile-home and non-space-constrained) systems, 
appendix M1 defines a default fan power coefficient of 441 W/1000 scfm 
and a default fan heat coefficient of 1,505 Btu/h/1000 scfm. See, e.g., 
appendix M1, section 3.3.e. In appendix M1, for both the default fan 
power coefficient and default fan heat coefficient, the same 
coefficient is used for both the full-load and part-load tests.
---------------------------------------------------------------------------

    \10\ The different default fan power and default fan heat 
coefficients for mobile-home and space-constrained systems as 
compared to conventional systems reflect the lower duct pressure 
drop expected for such systems in field operation--the lower values 
are consistent with the lower external static pressure levels 
required in testing of blower-coil systems intended for mobile home 
and spaced-constrained applications (see Table 4 of appendix M1).
---------------------------------------------------------------------------

    In the March 2022 CAC TP NOPR, DOE discussed a petition for waiver 
and interim waiver filed by Nortek on September 7, 2021, that requested 
an alternate test procedure that would define lower default fan power 
and fan heat coefficients for the part-load tests, instead of applying 
the same coefficients to both the full-load and part-load tests, as is 
done in appendix M1. 87 FR 16830, 16834-16835; see Nortek, EERE-2021-
BT-WAV-0025, No. 1 at pp. 4-9. In response, DOE published a notice that 
announced its receipt of the petition for waiver and denial of Nortek's 
petition for an interim waiver. Id. See 86 FR 63357 (``Notification of 
Petition for Waiver''). In the Notification of Petition for Waiver, DOE 
noted that applying the modified default fan power coefficients and 
default fan heat coefficients in appendix M1 to products such as those 
that are the subject of Nortek's petition was determined to be 
representative of the systems' performance and reflected the adoption 
of the recommendations of a working group formed to negotiate a notice 
of proposed rulemaking for energy conservation standards for CAC/HPs; 
and that the modified coefficients were subject to public comment 
during the 2016 test procedure rulemaking for CAC/HPs (``2016 CAC TP 
Rulemaking''). Id. See 82 FR 1426, 1452. DOE also noted that Nortek 
commented in support of the modified coefficients during the 2016 CAC 
TP Rulemaking. Id.
    In response to the issue raised by Nortek, DOE re-examined the 
furnace fan electrical power consumption data collected for the furnace 
fans rulemaking (see 79 FR 506, Jan. 3, 2014) that was used to develop 
the default fan power coefficients and default fan heat coefficients 
for coil-only products in appendix M1. DOE extended the prior analysis 
to examine both full-load and part-load air volume rates.\11\ DOE 
correlated the predicted power consumption with the predicted air 
volume rate for each furnace fan to determine adjusted values of the 
default fan power coefficients that may result in a more representative 
estimate of fan power and fan heat at reduced airflow conditions, 
compared to the coefficients currently defined in appendix M1. DOE's 
analysis indicated that at a reduced air volume rate of 75 percent, the 
average indoor fan power coefficient would be 360 W/1000 scfm for coil-
only CAC/HPs in a conventional (i.e., non-mobile-home and non-space-
constrained) installation. For mobile-home and space-constrained 
systems, the average indoor fan power coefficient would be 331 W/1000 
scfm.\12\ DOE also calculated the fan heat coefficients associated with 
these power input levels. The average indoor fan heat coefficients 
would be 1,228 Btu/hr/1000 scfm and 1,130 Btu/h/1000 scfm for 
conventional (i.e., non-mobile-home and non-space-constrained) and 
mobile-home/space-constrained installations, respectively. 78 FR 16830, 
16834-16835.
---------------------------------------------------------------------------

    \11\ To ensure consistency across analyses, DOE aggregated the 
data by applying market weightings to each type and brand of furnace 
model, using the same market shares that were used in the previous 
analysis for the 2016 CAC TP Rulemaking.
    \12\ For example, under DOE's proposed changes to appendix M1, 
for a two-stage coil-only system in a conventional application that 
has a cooling full-load air volume rate of 1640 scfm and a cooling 
minimum (i.e., part-load) air volume rate of 1,230, the default fan 
power at full load would be calculated as (441 W/1000scfm x 1640 
scfm = 723 W); and default fan power at part-load would be 
calculated as (360 W/1000scfm x 1230 scfm = 443 W).
---------------------------------------------------------------------------

    The analysis conducted by DOE for the March 2022 CAC TP NOPR 
resulted in higher default fan power coefficients and default fan heat 
coefficients at the reduced 75 percent air volume rate than the values 
presented in the Nortek waiver petition. DOE tentatively concluded that 
its analysis is a more appropriate representation of average furnace 
fan power consumption than the results presented by Nortek because (1) 
DOE's analysis relied on empirical test results while Nortek's analysis 
was theoretical, (2) DOE's analysis applied the same weighting factors 
\13\ from the 2016 CAC TP Rulemaking to ensure consistency, and (3) 
DOE's analysis considered constant-torque brushless-permanent-magnet 
``X13'' motors while Nortek's analysis did not. DOE proposed to amend 
the default fan power coefficients and default fan heat coefficients 
for coil-only fan power when operating at reduced air volume rates to 
reflect the results of its analysis. Id.
---------------------------------------------------------------------------

    \13\ DOE's analysis included weighting based on market share by 
brand, installations per cooling capacity range, and projected 
shares in 2021 for different furnace fan motor types.
---------------------------------------------------------------------------

    AHRI, Carrier, Emerson, the Joint Advocates, Lennox, Nortek, and 
Rheem all supported DOE's proposal to reduce the default fan power and 
fan heat coefficients for low-stage operation of coil-only 
conventional, mobile-home and space-constrained CACs. (AHRI, No.25 at 
p.3; Carrier, No.15 at p.2; Emerson, No.14 at p.1; Joint Advocates, 
No.18 at p.1; Lennox, No.19 at p.2; Nortek, No.13 at p.1; Rheem, No.21 
at p.1) Carrier, the Joint Advocates, and Lennox all stated that DOE's 
proposal to include a lower default fan power coefficient at part-load 
airflows would improve the representativeness of testing for two-stage 
coil-only systems over the current approach in appendix M1. (Carrier, 
No.15 at p.1; Joint Advocates, No.18 at p.1; Lennox, No.19 at p.2) Even 
though there was general support for DOE's proposals, several comments 
were received on the specific proposed values and the assumptions made 
in order to calculate them. The following sections detail these 
specific comments.
b. BPM Market Penetration
    Despite supporting DOE's proposal to establish a second default fan 
power coefficient representing low-stage operation, AHRI argued that 
DOE's proposed part-load default fan power and heat coefficients were 
still higher than they should be. (AHRI, No.25 at pp. 2-3) Carrier, 
Daikin, Emerson, Lennox, Nortek, and Rheem all agreed with the AHRI 
comment that the part-load default fan power and heat coefficients 
should be lower than the proposed values. (Carrier, No.15 at p.2; 
Daikin, No.24 at p.1; Emerson, No.14 at p.1; Lennox, No.19 at p.2; 
Nortek, No.13 at pp.1-2; Rheem, No.21 at pp.1-2)
    A key factor in AHRI's argument was that the actual market 
saturation rate of furnace fans installed with higher-efficiency 
brushless permanent magnet ``BPM'' \14\ fan motors is higher than 
assumed in the analyses presented by DOE. (AHRI, No.25 at pp.2-3) DOE 
first

[[Page 64557]]

presented its assumptions regarding relative prevalence of BPM motors 
for furnace fans in a December 5, 2016, Technical Support Document 
(``TSD'') used for the concurrent energy conservation standards 
(``ECS'') rulemaking. EERE-2014-BT-STD-0048-0098 (``December 2016 CAC 
ECS TSD''). In that document, DOE described its findings that in 
2021,\15\ the estimated mix of blower types in existing furnaces would 
be 77 percent permanent split capacitor (``PSC''), 15 percent constant-
speed BPM, and 9% constant-torque BPM. (EERE-2014-BT-STD-0048-0098, 
page 7-16) DOE assumed the same proportion of furnace fan motor types 
in its analysis for the March 2022 CAC TP NOPR.
---------------------------------------------------------------------------

    \14\ In their comment, AHRI used the term ``electronically 
commutated motor'' (ECM) to describe higher-efficiency motors 
available in the furnace fans market. However, all instances in this 
final rule have been changed to ``brushless permanent magnet'' (BPM) 
which better describes the motor construction.
    \15\ At the time the 2016 CAC ECS TSD was drafted, the proposed 
compliance date for amended standards was Jan. 1, 2021--therefore 
DOE forecasted the fan motor proportions in the anticipated year 
that standards would come into effect. In the January 2017 direct 
final rule regarding energy conservation standards (82 FR 1786, 
January 6, 2017) (``January 2017 CAC ECS Direct Final Rule''), 
however, the compliance date was delayed by two years to January 1, 
2023. DOE did not provide estimates of assumed furnace fan motor 
composition in the year 2023.
---------------------------------------------------------------------------

    In order to support its claim that the market saturation rate of 
BPM furnace fan motors was higher than the rate estimated by DOE, AHRI 
cited the 2019 compliance date for efficiency standards for furnace 
fans and stated that nearly all new furnaces shipped since 2019 have 
exclusively used BPMs. (AHRI, No.25 at pp.2-3) AHRI also claimed that 
the pending refrigerant change in the U.S. will require replacement of 
R-410A systems in both indoor and outdoor units for CAC systems, 
starting in 2025. AHRI asserted that due to these regulations, 
consumers with older furnaces would be more likely to simultaneously 
replace their furnaces at the same time as a whole-system CAC 
replacement, leading to a wave of newly installed furnace fans using 
BPM fan motors. Id. AHRI then forecasted the number of installed 
furnaces and percent share of furnaces with BPM furnace fans using 
DOE's estimates for equipment retirement Weibull curves, AHRI 
historical shipments data,\16\ and 2015 Residential Energy Consumption 
Survey (RECS) microdata.\17\ Ultimately, AHRI forecasted the 
penetration of BPM furnace fan motors to reach 50 percent by 2025. Id. 
NCP and Nortek both supported AHRI's analysis regarding the relative 
prevalence of furnace fans having BPM motors, stating that the Fan 
Energy Rating (FER) standards effectively obsoleted PSC motors in new 
furnace fans in favors of BPM motors. (NCP, No.16 at pp.8-9; Nortek, 
No.13 at p.2) NCP reiterated AHRI's claim that future refrigerant 
regulations could increase the pace of furnace replacements and thus 
accelerate the adoption of furnace fans with BPM motors. (NCP, No.16 at 
p.8)
---------------------------------------------------------------------------

    \16\ AHRI historical shipments estimates available online at: 
https://ahrinet.org/resources/statistics/historical-data/furnaces-historical-data.
    \17\ Residential Energy Consumption Survey data available online 
at: https://www.eia.gov/consumption/residential/data/2015/.
---------------------------------------------------------------------------

    To evaluate AHRI's claims about furnace fan BPM penetration rates, 
DOE reconstructed AHRI's analysis using RECS microdata and engineering 
assumptions about typical furnace lifetime and historical prevalence of 
BPM fan motors in furnace fans. DOE estimated the annual inflows and 
outflows (i.e., new sales and decommissioning at end-of-life) of BPM 
furnace fan motors, using the assumption that all new furnace fan 
motors would be BPM in years 2019 and onwards. Because AHRI did not 
explicitly describe how hypothetical refrigerant regulations would 
translate into accelerated uptake in furnace fans having BPM motors, 
DOE did not account for an increased rate of ``whole-system'' CAC 
replacements (and therefore furnace fan replacements) when evaluating 
furnace fan BPM penetration forecasts. Using these assumptions, DOE 
estimates that the percentage of installed BPM furnace fan motors in 
2021 to be 29 percent (as compared to 24 percent \18\ estimated in the 
December 2016 CAC ECS TSD). Further, DOE's estimates support AHRI's 
claim that the installed base of BPM furnace fans is likely to grow to 
40 percent by 2023 and 50 percent by the year 2025. Therefore, DOE has 
used these values of BPM market penetration to re-evaluate the NOPR 
analysis to calculate default low-stage fan power coefficients and fan 
heat coefficients in the next section.
---------------------------------------------------------------------------

    \18\ BPM estimate from 2016 CAC ECS TSD reflects the sum of CT-
BPM (9%) and CA-BPM (15%).
---------------------------------------------------------------------------

c. Determining Low-Stage Coefficients
    In consideration of DOE's proposals regarding default fan power 
coefficients, AHRI also asserted that DOE's analysis included incorrect 
assumptions about the relationship between electrical power consumption 
and delivered airflow, which they claimed should be a cubic 
relationship based on fan affinity laws. AHRI provided aggregated data 
from a selection of 78 furnace fans to support their assertions. Id. at 
pp.3-4. Lennox and Rheem reiterated AHRI's comment, stating that the 
application of the same default coefficient at part-load airflows is 
not representative of the performance of the two-stage equipment 
operation, as the fan efficiency improves as airflow is reduced thus 
increasing overall system efficiency. (Lennox, No.19 at p.2, Rheem, 
No.21 at pp.1-2) Lennox and Rheem also elaborated that fan affinity 
laws show that fan speed and power have a cubic relationship, not the 
constant relationship \19\ currently used in the test procedure. Id. 
AHRI further claimed that of the 78 collected furnace fans in their 
data set, there was not a statistically significant difference in full-
load performance (measured in Watts per cfm) between models having 
furnace fans with PSC motors and models having furnace fans with PBM 
motors. As a result, AHRI did not argue that the full-load default fan 
power and heat coefficients should be changed but did suggest lower 
default fan power and fan heat coefficients low-stage operation. AHRI 
proposed default low-stage fan power coefficients of 322 W/1000 scfm 
for conventional systems and 296 W/1000 scfm for mobile-home/space-
constrained systems.\20\ (AHRI, No.25 at pp.3-4) As indicated, Carrier, 
Daikin, Emerson, Lennox, Nortek, and Rheem all referenced the AHRI 
analysis in their comments and supported the alternate default fan 
power coefficients proposed by AHRI. (Carrier, No.15 at p.2; Daikin, 
No.24 at p.1; Emerson, No.14 at p.1; Lennox, No.19 at p.2; Nortek, 
No.13 at pp.1-2; Rheem, No.21 at pp.1-2)
---------------------------------------------------------------------------

    \19\ The DOE test procedure does not prescribe a constant 
default fan power, but rather a constant default fan power 
coefficient, so that the calculated fan power varies linearly with 
air volume rate. See appendix M1, sections 3.3, 3.5.1, 3.7, and 
3.9.1.
    \20\ AHRI also provided corresponding default fan heat 
coefficients of 1099 Btu/h/1000scfm and 1010 Btu/h/1000scfm for 
conventional and mobile-home/space-constrained coil-only CACs, 
respectively.
---------------------------------------------------------------------------

    DOE understands the theoretical basis of fan laws which describe a 
cubic relationship between fan shaft power and delivered air volume 
rate for an idealized fan. However, real fan shaft power does not 
always consistently follow the fan laws \21\ and motor efficiency 
generally decreases as shaft power decreases from rated load,\22\ which 
would cause motor input power to deviate from the cubic relationship 
even if the shaft power followed it. The AHRI comment does not provide 
a more

[[Page 64558]]

detailed breakdown of analytical results allowing confirmation of 
general consistency of the two analytical approaches. As noted, DOE has 
re-evaluated the NOPR analysis to calculate default low-stage fan power 
coefficients and fan heat coefficients, using the assumption that BPM 
furnace fan penetration is 40 percent in the year 2023 (the compliance 
date of CAC energy conservation standards in terms of appendix M1 
metrics). 10 CFR 430.32(c)(5). DOE re-analyzed the same dataset used in 
the furnace fans rulemaking and applied a proportion of 40 percent BPM 
and 60 percent PSC motors, while keeping all other elements of the 
analysis unchanged (see 79 FR 506, Jan. 3, 2014). For the reasons 
described in section III.C.1.e of this document, DOE did not consider 
separate default fan power coefficients for space-constrained coil-only 
CACs and is instead continuing to treat mobile-home and space-
constrained systems jointly. This evaluation results in default low-
stage fan power and heat coefficients that are lower than the values 
proposed in the March 2022 CAC TP NOPR, and DOE is adopting these lower 
values in this final rule. The fan motor re-weighting had negligible 
impact on the full-load airflow values for default fan power and 
default fan heat coefficients, therefore, DOE is not amending the full-
load values in this final rule, consistent with comments received from 
AHRI. (AHRI, No.25 at p.3) The results of DOE's analysis are summarized 
in Table III-1.
---------------------------------------------------------------------------

    \21\ This catalog of several indoor air handling units 
demonstrates on the 6th page examples of fan performance curves, 
where the fan efficiency does not always follow a simple quadratic 
curve: https://content.greenheck.com/public/DAMProd/Original/10002/IAH_catalog.pdf.
    \22\ As per ANSI/AMCA Standard 241-21 (Test Procedure for 
Calculating Fan Energy Index (FEI) for Commercial and Industrial 
Fans and Blowers), the motor efficiency for variable-speed motors is 
not always directly proportional to the load, as demonstrated in 
Figure F.3. Source: https://www.amca.org/assets/resources/public/pdf/Publications/AMCA-214-21.pdf.

               Table III-1--Default Fan Power and Fan Heat Coefficients for Coil-Only CACs and HPs
----------------------------------------------------------------------------------------------------------------
                                                                                Default fan
                                                                Air volume         power       Default fan heat
                         System type                             rate (%)     coefficient (W/ coefficient (Btu/h/
                                                                                 1000scfm)         1000scfm)
----------------------------------------------------------------------------------------------------------------
Conventional Coil-Only......................................             100             441                1505
                                                                          75             335                1143
Mobile-Home and Space-Constrained Coil-Only.................             100             406                1385
                                                                          75             308                1051
----------------------------------------------------------------------------------------------------------------

d. Interpolated Coefficients Between 75 and 100 Percent Air Volume Rate
    In the March 2022 CAC TP NOPR, DOE also stated that the reduced air 
volume rate used for low-stage operation of two-stage coil-only systems 
may be higher than 75 percent of the full-load air volume rate, if the 
manufacturer's instructions specify a higher part-load air volume rate. 
DOE proposed that in such cases, (i.e., in any case where the reduced 
air volume rate is greater than 75 percent of the full-load air volume 
rate) the default fan power values associated with full-load air volume 
rate be used. However, DOE hypothesized that in these scenarios, the 
appropriate default fan power coefficient and default fan heat 
coefficient may be values between the reduced values discussed above 
and the values used for full-load air volume rate. DOE set out two 
alternative options to its proposed approach: (1) allowing the reduced 
value up to a threshold value, e.g., 80 percent of full-load air volume 
rate, above which the full-load value would be required, and (2) 
requiring a linear interpolation of the default fan power coefficient 
between the reduced value at 75 percent of full-load air volume rate to 
the full-load value at 100 percent.\23\ 78 FR 16830, 16835.
---------------------------------------------------------------------------

    \23\ For example, for non-mobile-home and non-space-constrained 
systems, if a linear interpolation of the default fan power 
coefficient is required, it would be equal to 360 + (441-
360)*(%FLAVR-75%)/(100%-75%), where %FLAVR is the reduced air volume 
rate used for the test expressed as a percentage of the full load 
air volume rate.
---------------------------------------------------------------------------

    AHRI, Carrier, Daikin, Emerson, Lennox, and Nortek all supported 
the second alternative option set forth by DOE, i.e., requiring a 
linear interpolation of the default fan power coefficient based on 
percentage full-load air volume rate. (AHRI, No.25 at p.6; Carrier, 
No.15 at p.2; Daikin, No.24 at p.1; Emerson, No.14 at pp.1-2; Lennox, 
No.19 at p.2; Nortek, No.13 at p.1) AHRI provided a table of power 
consumption rate as a function of airflow percentage and stated that a 
third-order equation would be most accurate, however intermediate 
values for default fan power coefficient would be most easily 
calculated using linear interpolation. (AHRI, No.25 at pp.4-6)
    Based on the comments, DOE is finalizing the approach of requiring 
linear interpolation of default fan power and default fan heat 
coefficients for all tests where the specified airflow is between 75 
percent and 100 percent of the full load air volume rate.
e. Considerations for Space-Constrained Systems
    As previously mentioned in section III.C.1.b, NCP supported AHRI's 
claims that due to the FER furnace fan standards coming into effect in 
2019, and due to anticipated refrigerant regulations, the relative 
penetration rate of furnace fans with BPM motors is higher than the 
proportion estimated by DOE in the January 2017 CAC TP Final Rule. 
(NCP, No.16 at pp.8-9) NCP also remarked that DOE's proposal for 
default fan power coefficients implies that space-constrained coil-only 
units are similar to those of mobile homes, and implies that both 
should use a default fan power and capacity adjustment that is 
representative of operation at a minimum external static pressure (ESP) 
of 0.30 inches w.c.\24\ NCP asserted that data based on mobile homes is 
not an appropriate basis for space-constrained condensing units used in 
multi-family housing applications. NCP claimed that although the size 
of the indoor units is similarly restricted in mobile-home and space-
constrained applications, mobile-home applications do not limit the 
size of the outdoor unit in the same way as space-constrained 
installations, which require a smaller footprint for the condensing 
unit. NCP elaborated that this discrepancy allows for mobile-home 
systems to have a relatively larger condenser coil surface area 
(providing improved performance) and that their models of space-
constrained outdoor units do not have sufficient space to increase the 
condenser coil size. NCP thus asserted that the default fan power 
coefficients proposed by DOE in the March 2022 CAC TP NOPR remains 
unrealistic for NCP's space-constrained CAC systems and would prohibit 
NCP from meeting the minimum energy efficiency standard. NCP requested 
that if the Department does not continue to waive requirements for 
coil-only testing of space-constrained condensing units, DOE should 
amend the default fan

[[Page 64559]]

power and fan heat coefficients to reflect real world conditions. (NCP, 
No.16 at pp. 7-8) NCP provided confidential information regarding the 
performance of their ``Through-the-Wall'' (TTW) space-constrained 
condensing units when paired with various indoor unit air handlers, 
including different NCP-branded air handlers and with other brands of 
furnaces (indicative of a coil-only installation). NCP then 
incorporated its findings along with the data provided by AHRI and 
proposed a default fan power coefficient of 321 Watts per 1000 scfm for 
space-constrained coil-only CAC systems operating at low-stage airflow. 
Id. at p.9.
---------------------------------------------------------------------------

    \24\ Appendix M1 requires that both ducted space-constrained and 
ducted mobile-home CACs be tested at a minimum ESP of 0.30 inches 
w.c. 87 FR 16834 (Mar. 24, 2022) (citing 82 FR 1426, 1453 (Jan. 5, 
2017)).
---------------------------------------------------------------------------

    In response to NCP's assertion that separate test procedure 
considerations should be given for default fan power coefficients for 
space-constrained CAC systems vs those for mobile-home CAC systems, DOE 
notes that this topic was previously discussed in the January 2017 CAC 
TP Final Rule. In that rule DOE determined, with stakeholder support, 
appropriate default fan power and default fan heat coefficients for 
mobile home coil-only systems required to be tested at a minimum 
external static pressure of 0.30 in. w.c. 82 FR 1426, 1451-1452. DOE 
also noted in that final rule that recommendation #2 of the January 
2016 Appliance Standards and Rulemaking Federal Advisory Committee 
(ASRAC) CAC/HP Working Group Term Sheet (2016 CAC Term Sheet) 
recommended 0.30 inches w.c. as the minimum external static pressure 
requirement for testing space-constrained CACs Id. DOE is maintaining 
the determination from the January 2017 CAC TP Final Rule and the 
current test procedure approach, which uses the same default fan power 
coefficient and default fan heat coefficient for space-constrained and 
mobile home CAC.
2. Variable-Speed Coil-Only Test Procedure
a. Background
    As discussed, appendices M and M1 contain provisions for testing 
split-system CAC/HPs equipped with ``coil only'' indoor units that, in 
a field installation, are paired with an existing furnace or other air 
handler that includes the fan required to circulate conditioned air 
through ductwork. These provisions apply to single-stage and two-stage 
systems and address only two levels of air volume rate, for full-load 
and minimum operation.\25\ Appendices M and M1 do not include 
provisions for testing variable-speed systems equipped with coil-only 
indoor units (``VSCO'' CACs). In the March 2022 CAC TP NOPR, DOE 
discussed waiver requests that it had received from multiple 
manufacturers regarding the test provisions for VSCO CACs. 82 FR 16830, 
16836-16837. The various waiver requests are summarized in this final 
rule in Table III-2.
---------------------------------------------------------------------------

    \25\ Section 3.1.4.1.1.c (cooling full-load air volume rate), 
section 3.1.4.2.c (cooling minimum air volume rate), section 
3.1.4.4.2.c (heating full-load air volume rate), and section 
3.1.4.5.2.d (heating minimum air volume rate) of appendix M1.
---------------------------------------------------------------------------

    With the exception of the Goodman Manufacturing Company, L.P. 
(``Goodman'') petition for waiver (86 FR 40534 (July 28, 2021)), all 
petitioners submitted petitions for waiver for products that use ``non-
communicative'' conventional controls, i.e., controls that use low-
voltage on-off signals from the thermostat to indicate the need for 
conditioning in the conditioned space. As required under the specified 
alternate test procedures for these ``non-communicative variable-speed 
coil-only systems,'' they must be tested according to the appendix M 
provisions applicable to variable-speed systems (e.g., three different 
compressor speeds in the cooling mode), except that the subject systems 
must be tested using the full-load cooling air volume rate at all test 
conditions. (GD Midea, EERE-2017-BT-WAV-0060, No. 1, pp. 1-3; TCL, 
EERE-2018-BT-WAV-0013, No. 1, pp. 2-4; LG, EERE-2019-BT-WAV-0023, No. 
1, pp 3-4) DOE noted that the waivers for non-communicative systems 
indicated only that ``compressor speed varies based only on controls 
located on the outdoor unit.'' (GD Midea, EERE-2017-BT-WAV-0060, No. 1, 
p. 6; TCL, EERE-2018-BT-WAV-0013, No. 1, p. 4; LG, EERE-2019-BT-WAV-
0023, No. 1, pp 2) An interim test procedure waiver was also granted to 
Goodman for their ``communicative'' variable-speed, coil-only CAC/HPs. 
Goodman's petition claimed that for their systems, both the outdoor 
unit and indoor coil communicate with each other to control the 
variable-speed compressor, along with the multi-speed indoor fan. 86 FR 
40534, 40539. The Goodman interim waiver test procedure specifies use 
of the cooling full-load air volume rate for the full-load cooling and 
full-load heating tests; and the cooling minimum air volume rate for 
the cooling minimum, heating minimum, cooling intermediate, and heating 
intermediate tests. Id.

               Table III-2--Status and Details of Variable-Speed, Coil Only (VSCO) Waiver Requests
----------------------------------------------------------------------------------------------------------------
          Manufacturer             Petition description                  Docket                      Status
----------------------------------------------------------------------------------------------------------------
GD Midea Heating & Ventilating   Non-communicating VSCO.  EERE-2017-BT-WAV-0060..............  Interim and
 Equipment Co., Ltd. (GD Midea).  Full load air volume                                          Waiver Granted.
                                  rate used for
                                  intermediate and
                                  minimum.
TCL air conditioner (zhongshan)  Non-communicating VSCO.  EERE-2018-BT-WAV-0013..............  Interim and
 Co. Ltd. (``TCL AC'').           Full load air volume                                          Waiver Granted.
                                  rate used for
                                  intermediate and
                                  minimum.
LG Electronics U.S.A., Inc.      Non-communicating VSCO.  EERE-2019-BT-WAV-0023..............  Interim Granted.
 (LGE).                           Full load air volume
                                  rate used for
                                  intermediate and
                                  minimum.
Goodman........................  Communicating VSCO.      EERE-2021-BT-WAV-0001..............  Interim Granted.
                                  Minimum air volume
                                  rate used for
                                  intermediate and
                                  minimum.
----------------------------------------------------------------------------------------------------------------

    In the March 2022 CAC TP NOPR, DOE explained that it was 
reconsidering its approach to the waivers for the non-communicative 
VSCO systems. First, DOE explained that the waiver petitions had not 
provided information regarding, nor had DOE evaluated, the compressor 
speed selections used for different test conditions specified in 
appendix M or M1. 87 FR 16830, 16836. DOE elaborated that it had also 
not compared these speed selections with those used by blower-coil 
variable speed systems for the same test conditions. Id. DOE determined 
that based on the

[[Page 64560]]

information received and evaluated, it could not conclude that the 
alternate test procedures specified in the waivers are representative 
of average use cycles of CAC/HPs. Id. DOE proposed provisions as 
generally prescribed in the relevant waivers, except that, for all 
variable-speed coil-only systems, regardless of communicative 
capability, use of a reduced-air volume rate would be allowed for part-
load operation, i.e., using the cooling minimum air volume rate for the 
cooling minimum, heating minimum, cooling intermediate, and heating 
intermediate tests. 87 FR 16830, 16837-16838. The proposed test 
procedure also incorporated the reduced default fan power and default 
fan heat coefficients at reduced air volume rates discussed in section 
III.C.1 of this document.
    Regarding indoor airflow rate for VSCO systems, DOE pointed out 
that the test procedure for two-stage coil-only systems is premised on 
the system using a two-stage thermostat and associated wiring that 
responds to indoor temperature measurements and sends voltage signals 
that enable two-stage control of both the compressor speed and the 
indoor fan speed. 87 FR 16830, 16836-16837. DOE similarly assumed the 
presence of necessary wiring for the installation of variable-speed 
systems. Id. DOE elaborated that if the system does not include the 
capability to control an existing furnace fan at two air volume rates, 
the manufacturer would have the option of specifying minimum/
intermediate air volume rates equal to the full-load air volume rate. 
Id.
    Regarding compressor speed control for VSCO systems, DOE proposed 
to define ``communicating control'' in the context of variable-speed, 
coil-only CAC/HPs in order to differentiate between the test procedure 
provisions that would be applicable to communicating systems from those 
applicable to non-communicating systems. 87 FR 16830, 16837-16838. See 
section III.C.2.b. DOE further proposed provisions for setting 
compressor speed reflecting the attributes of the controls. 
Specifically, DOE proposed to require that non-communicative variable-
speed coil-only systems be tested using an on-off control signal 
consistent with the control characteristics and also eliminating the 
EV test for cooling and H2V for heating as well 
as including H22, H21, and H31 for 
heating. In contrast, DOE proposed that systems that meet the newly 
proposed criteria for ``communicating'' control would use compressor 
speeds and tests consistent with the existing variable-speed test 
procedure for blower-coil systems. Id.
    With respect to DOE's proposal to add testing provisions for VSCO 
CACs in appendix M1, Carrier, Joint Advocates, Lennox, Nortek, and 
Rheem commented that they supported DOE's proposals to add testing 
provisions for variable-speed coil-only CAC/HPs. (Carrier, No.15 at 
p.1, Joint Advocates, No.18 at p.2, Lennox, No.19 at p.3, Nortek, No.13 
at p.2, Rheem, No.21 at p.2) Carrier stated that they agreed that a 
communicating and non-communicating procedure should be created, and 
supported DOE's proposed test procedure for each type of system. 
(Carrier, No.15 at p.1) The Joint advocates added that they supported 
incorporating provisions for testing variable-speed coil-only units to 
ensure that the test procedure reflects differences in system controls 
architecture between communicating and non-communicating systems. 
(Joint Advocates, No.18 at p.2) They further commented that DOE's 
hybrid approach for aligning minimum air volume requirements between 
two-capacity and variable-speed coil-only units (for both communicating 
and non-communicating systems) was logical, as non-communicating 
systems have characteristics of both variable-speed and two-stage 
systems due to limitations of the less sophisticated control systems. 
Id. Lennox stated that DOE's proposal provides a consistent test method 
according to defined system capabilities while allowing for expanded 
opportunity for variable speed equipment to be installed in replacement 
applications with existing furnace or modular blowers. (Lennox, No.19 
at p.3) Nortek explicitly stated that they were in favor of adopting 
the test procedures that were contained in the waivers, giving the 
Goodman waiver (86 FR 40534 (July 28, 2021)), as an example. AHRI 
commented that they agreed that systems meeting the criteria for 
variable-speed communicating coil-only CAC or HP definition should 
follow the existing variable-speed test procedure, although AHRI 
proposed an alternate definition for communicating control as described 
in section III.C.2.b of this document. (AHRI, No.25 at p.6)
b. Test Differences Based on Communicating Capability
    As previously stated, the test procedure for two-stage coil-only 
systems is premised on the system using a two-stage thermostat and 
associated wiring that responds to indoor temperature measurements and 
sends voltage signals that enable two-stage control of both the 
compressor speed and the indoor fan speed. A more sophisticated control 
approach is required to enable a variable speed system to modulate 
compressor speed control (e.g., proprietary thermostat, serial 
communication wiring, and/or electronic sensors at the indoor coil). In 
the March 2022 CAC TP NOPR, DOE proposed to define ``variable-speed 
communicating oil-only central air conditioner or heat pump'' in 
section 1.2 of appendix M1, to distinguish variable-speed coil-only 
systems with such controls, as a variable-speed compressor system 
having a coil-only indoor unit that is installed with a control system 
that (1) communicates the difference in space temperature and space 
setpoint temperature (not a setpoint value inferred from on/off 
thermostat signals) to the control that sets compressor speed; (2) 
provides a signal to the indoor fan to set fan speed appropriate for 
compressor staging and air volume rate; and (3) has installation 
instructions indicating that the required control system meeting both 
(1) and (2) must be installed. 87 FR 16830, 16837.
    DOE also proposed to define variable-speed systems that do not have 
this communicating feature as a variable-speed compressor system having 
a coil-only indoor unit that does not meet the definition of variable-
speed communicating coil-only central air conditioner or heat pump. Id.
    DOE elaborated that variable-speed coil-only systems that meet the 
``communicating'' definition would be tested like any other variable-
speed system, except that the heating full-load air volume rate would 
be equal to the cooling full-load air volume rate, and the intermediate 
and minimum cooling and heating air volume rates would all be the 
higher of (1) the rate specified by the installation instructions 
included with the unit by the manufacturer and (2) 75 percent of the 
full-load cooling air volume rate. Id.
    DOE further proposed that those variable-speed coil-only systems 
that are not ``communicating'' as defined above would be tested with 
additional limitations as if they have some variable-speed system 
characteristics and some two-stage coil-only system characteristics. 
Specifically, (a) the outdoor unit and/or the indoor unit would be 
provided with a control signal indicating operation at high or low 
stage, rather than testing with compressor speed fixed at specified 
speeds, and (b) air volume rates would be determined consistent with 
the requirement for two-stage coil-only systems. Id. A key implication 
of (a) is that there would be no intermediate compressor speed 
operation. Under DOE's proposed test procedure, many of

[[Page 64561]]

the requirements associated with variable-speed operation would, 
however, be retained. For example, such systems would be allowed to 
have ``minimum speed-limiting'' control for heat pump mode (see the 
alternative calculations representing minimum-speed operation in 
appendix M1, section 4.2.4.b). The test method for non-communicating 
variable-speed coil-only systems would include requiring tests for 
minimum-speed operation for both the 35 [deg]F and 17 [deg]F heating 
test conditions so that the HSPF2 calculations utilize test results for 
appropriate compressor speeds. Also, the full compressor speed during 
heating mode operation would be allowed to vary with outdoor 
temperature, there would be an H1N test to represent the 
nominal capacity, and the same provisions for calculation of full-speed 
capacity and power applied to conventional variable-speed systems would 
be used (see, e.g., the calculations in appendix M1, sections 3.6.4, 
4.2.4.c and 4.2.4.d). If a manufacturer chooses to run the optional 
H12 test (i.e., if compressor speed for the H1N 
test is different than compressor speed for the H32 test, 
and the manufacturer chooses to run the H12 test rather than 
use the standardized slope factors described in appendix M1, section 
3.6.4.b), then the test would be run with over-ride of compressor speed 
using the same speed as used for the H32 test. This is the 
only test for which such over-ride would be allowed.
    To ensure consistency of testing, it may be necessary for 
manufacturers to certify whether a variable-speed coil-only rating is 
based on non-communicating or communicating control. However, this 
change was not proposed in the March 2022 CAC TP NOPR and may be 
considered in a separate rulemaking.
    In the March 2022 CAC TP NOPR, DOE acknowledged that there may be 
variable-speed control technology that cannot be tested according to 
the proposed test approach described previously for non-communicating 
variable-speed coil-only systems. 87 FR 16830, 16838. Specifically, the 
test approach may not result in tests that meet the stability 
requirements for testing (i.e., the measurements might not meet the 
tolerance requirements in Table 2 of ANSI/ASHRAE 37-2009, ``Methods of 
Testing for Rating Electrically Driven Unitary Air-Conditioning and 
Heat Pump Equipment'' (``ASHRAE 37-2009''), which is incorporated by 
reference by the DOE test procedure). Or the proposed test procedure 
might evaluate such a basic model in a manner so unrepresentative of 
its true energy consumption characteristics as to provide materially 
inaccurate comparative data. Id. DOE stated that in this case, the 
manufacturer would be able to petition DOE for a waiver and include a 
suggested alternate test procedure as provided in 10 CFR 430.27. DOE 
elaborated that as part of its review of such a waiver and alternate 
test procedure, DOE would consider the correlation between results of a 
suggested alternate test procedure and results of testing when using 
the two-stage two-wire controls expected to be available in a general 
coil-only system installation, recognizing that the latter testing may 
involve dynamics that exceed the measurement tolerances discussed 
above. DOE would also consider the control hardware involved in 
achieving appropriate control for indoor and outdoor conditions and 
some understanding of how the control works. Id.
    With respect to DOE's proposal to define variable speed 
communicating coil-only CACs and HPs, Emerson supported the 
differentiation of communicating and non-communicating variable speed 
CACs that maintains the ability to set compressor speed and optimize 
airflow relative to the compressor speed. (Emerson, No.14 at p.3) The 
Joint Advocates supported DOE's proposed definition but encouraged DOE 
to revise the definition to clarify that the installation instructions 
refer to those of the indoor unit (not of the control system). (Joint 
Advocates, No.18 at pp.2-3) AHRI commented that they supported the 
concept of the definition but recommended modifications to be more 
inclusive of other approaches. AHRI proposed an alternate definition as 
follows:
    Variable-Speed Communicating Coil-Only Central Air Conditioner or 
Heat Pump means a variable-speed compressor system having a coil-only 
indoor unit that is installed with communicative controls to change the 
compressor speed by 3 or more speeds and indoor air flow by 2 or more 
speeds and controls the system by monitoring the change in system 
control parameter/s and automatically sets the compressor speed, indoor 
air flow and other system components as required to maintain the indoor 
room temperature. (AHRI, No.25 at p.6)
    Carrier, Daikin, Nortek, and Samsung incorporated AHRI's proposed 
definition in their comments. (Carrier, No.25 at pp.2-3; Daikin, No.24 
at p.2; Nortek, No.13 at p.2; Samsung, No.22 at p.2) AHRI, Carrier, 
Daikin, Nortek, and Samsung all agreed that DOE's proposed definition 
is too restrictive and should be modified to allow for potential 
alternate control strategies that could be used to properly control 
compressor speed and coordinate with indoor fan speed. Id. AHRI, 
Daikin, and Samsung stated that communication of set point and indoor 
temperature is not the only parameter that can be used to set fan and 
compressor speeds, suggesting that it is not necessary to achieve 
proper compressor control, and provided hypothetical examples of other 
control parameters that could be used to set compressor speeds, such as 
outside air conditions, indoor humidity levels, or refrigerant 
pressures and temperatures. (AHRI, No. 25 at p.6; Daikin, No.24 at p.2; 
Samsung, No.22 at pp.1-2) Daikin elaborated that the DOE definition 
should be modified to allow for technology advancements in control 
technology and recommended a definition similar to the definition for 
``demand defrost control systems'', which requires that the control 
scheme ``monitor one or more parameters that always vary.'' (Daikin, 
No.24 at p.2) Samsung elaborated that DOE's proposal would require a 
communicating thermostat, which they claimed to be unnecessary for 
achieving appropriate compressor and fan control and stated would add 
unnecessary cost to the consumer. (Samsung, No.22 at pp.1-2)
    While DOE acknowledges that there may be other control approaches 
to set compressor speed other than approaches that communicate the 
difference in space temperature and space setpoint temperature, DOE 
notes that minimizing this difference between a controlled parameter 
and its setpoint is the key function of the control system, and use of 
this parameter to set conditioning system operation is a fundamental 
feature of most modern control systems. In its proposal, DOE 
distinguished between communicating and non-communicating based on 
whether the system includes this fundamental aspect of control systems. 
DOE premised its proposals on the understanding that non-communicating 
systems would likely encounter greater issues regarding the 
representativeness of field-versus-tested performance, as compared to 
communicating systems.
    As mentioned, DOE acknowledges that other control approaches may 
provide control represented adequately by the fixed-speed testing that 
is currently prescribed in its test procedures for CAC/HP system but 
given the fundamental difference in the control approach, i.e., not 
using information about the space temperature deviation from setpoint, 
DOE does not believe there has been sufficient

[[Page 64562]]

information provided confirming this adequacy. As DOE considers more 
comprehensive test procedure changes in a future rulemaking, it will 
further evaluate this issue and is open to revising the definition 
accordingly. Also, the proposed definition does not restrict other 
control parameters in addition to the space temperature offset from 
setpoint being used by the control system to set system operation. 
Hence, DOE is adopting the definition for communicating and non-
communicating variable-speed coil-only system as proposed.
    As previously introduced, DOE also considered that it may be 
necessary for manufacturers to certify whether a variable speed coil-
only rating is based on non-communicating or communicating control but 
did not propose any certification requirements in the March 2022 CAC TP 
NOPR and instead stated that these changes may be considered in a 
separate rulemaking. 87 FR 16830, 16838.
    In response, the Joint Advocates supported the concept that DOE 
require certification of VSCO units as communicating or non-
communicating and encouraged DOE to finalize all pertinent 
certification provisions as soon as possible. (Joint Advocates, No. 18 
at p. 2) As indicated, DOE may consider certification requirements in a 
separate rulemaking.
c. Applicability to Variable Speed Blower Coil Systems
    In the March 2022 CAC TP NOPR, DOE further discussed that 
installations using non-communicating controls may not be limited only 
to variable-speed coil-only systems but could also occur with variable-
speed blower-coil systems. 87 FR 16830, 16838. DOE noted that the 
proposed test procedure distinguishes between the testing approach used 
for coil-only configurations and the testing approach used for blower-
coil configurations. Id. DOE argued that as coil-only installations are 
much more likely than blower-coil installations to involve use of both 
the existing furnace fan and existing controls, the non-communicating 
test procedure should be reflective of coil-only installations because 
they are more representative than blower coil installations. Id.
    With respect to the applicability of the proposed VSCO testing 
provisions to variable speed blower-coil CACs and HPs, Emerson 
commented that the ability to set compressor speed and optimize airflow 
rate relative to compressor speed may be even more important in blower-
coil systems than in coil-only systems and requested that DOE address 
this point. (Emerson, No. 14 at p. 3) Trane similarly asserted that it 
is important that DOE addresses non-communicating, blower-coil variable 
speed systems in addition to the proposed provisions for coil-only 
systems. (Trane, No. 10 at p. 2) Trane stated that such blower-coil 
systems have the same issue of misrepresenting the applied performance 
(i.e., the performance measured in a field installation) by allowing 
them to use the communicating, variable speed procedures. Id. Trane 
elaborated that the wiring and control of such systems is obvious from 
the installation instructions, and they operate in a similar fashion to 
the furnace-coil (i.e., coil-only) combinations with one or two-stage 
fan operation. Id. Trane provided an example \26\ of such a product 
where a variable-speed CAC outdoor unit is certified with an indoor 
blower-coil unit only capable of one stage of airflow operation, and 
the connections are non-communicating 24V signals between equipment and 
thermostat. Id.
---------------------------------------------------------------------------

    \26\ Trane provided an example of a Bosch system with AHRI 
reference number 206395973 and provided a link to the installation 
instructions: https://www.bosch-thermotechnology.us/us/media/country_pool/documents/bosch_ids_bva15_iom_10.2020.pdf.
---------------------------------------------------------------------------

    DOE acknowledges the concerns expressed by Trane and Emerson that 
questions remain regarding use of non-communicating controls for 
blower-coil systems and whether the compressor and/or fan speeds used 
for testing such systems are representative of field operation. 
However, DOE initiated this rulemaking to address a focused group of 
known issues, including those that have been raised through the test 
procedure waiver process. As noted in the March 2022 CAC TP NOPR, DOE 
limited its proposals addressing potential concerns about variable-
speed systems to coil-only systems and may more comprehensively address 
these issues for all variable-speed systems in a future rulemaking that 
will satisfy the 7-year lookback requirements (see 42 U.S.C. 
6293(b)(1)(A)). 87 FR 16830, 16838.
d. Represented Values and Testing Requirements
    Coil-only testing approaches for variable-speed systems address the 
installation of variable-speed technology in which the newly installed 
system uses existing components, for example an existing furnace fan. 
For single-capacity and two-capacity split-system air-conditioners, 
certification requirements anticipate this likely installation scenario 
by requiring that such models include performance representations with 
a coil-only combination representative of the least-efficient 
combination in which the outdoor unit is sold (see 10 CFR 
429.16(a)(1)). For variable speed split-system air conditioners, 
represented values are required for every individual combination 
distributed in commerce, including all coil-only and blower-coil 
combinations (see 10 CFR 429.16(a)(1)). However, there is no 
requirement that each model of outdoor unit include at least one 
representation based on the least-efficient coil-only combination 
distributed in commerce. In the March 2022 CAC TP NOPR, DOE considered 
whether such a requirement may be appropriate for variable-speed 
systems. 87 FR 16830, 16838-16839.
    Through a review of product datasheets and installation 
instructions, DOE found that there is a wide range of instruction 
regarding whether variable-speed CAC systems must be paired with 
specific models of indoor units and/or air movers (e.g., furnaces) in 
order to achieve the represented performance. Id. DOE identified that 
some literature is very clear that achieving the rated performance for 
a given outdoor unit is contingent on installation with specific 
components (e.g., communicating controls and indoor fans capable of 
variable-speed operation), while other literature does not mention the 
need for such components. Id. DOE identified that this latter group is 
not limited to brands that have been granted test procedure waivers or 
interim waivers for testing variable-speed coil-only systems, 
indicating that the issue is more broadly applicable to variable-speed 
CAC installations and it is possible that variable-speed systems are 
being installed in coil-only applications for which representations of 
performance are not representative of actual performance (because the 
represented values are based on blower-coil pairing while the 
installation scenario is coil-only). Id. However, because less than 5 
percent of variable speed system installations are coil-only \27\ and 
the number of certified combinations of VSCO systems is a small 
percentage \28\ of overall variable

[[Page 64563]]

speed system certifications, DOE concluded that VSCO installations are 
not likely representative of variable speed system operation as a 
whole. Id.
---------------------------------------------------------------------------

    \27\ Based on information DOE has from the previous energy 
conservation standards rulemaking pertaining to central air 
conditioners and heat pumps. See 82 FR 1786.
    \28\ For example, there are roughly 27,000 combinations listed 
in the AHRI Database for which a non-zero intermediate indoor air 
volume rate is listed, indicating that the combination is a 
variable-speed model. DOE reviewed the current certifications in the 
certification compliance management system and found that there are 
approximately 400 variable-speed coil-only combinations, 
representing roughly 1.5 percent of the total variable speed 
combinations certified to the Department.
---------------------------------------------------------------------------

    In the March 2022 CAC TP NOPR, in order to improve 
representativeness of the representations of VSCO installations DOE 
proposed tested-combination requirements pertaining to variable speed 
systems, summarized here in Table III-3. 87 FR 16830, 16839.

Table III-3--Proposed Tested Combination Requirements for Variable Speed
                            Split-System CACs
------------------------------------------------------------------------
                                                      Required tested
                    Scenario                            combination
------------------------------------------------------------------------
Outdoor unit is distributed in commerce with any  Variable Speed Non-
 non-communicating coil-only combination(s).       Communicating Coil-
                                                   Only.
Outdoor unit is distributed in commerce with any  Variable Speed
 communicating coil-only combination(s), but no    Communicating Coil-
 non-communicating coil-only combination.          Only.
Outdoor unit is only distributed in commerce      Variable Speed Blower-
 with blower-coil combinations.                    Coil.
------------------------------------------------------------------------

    In the March 2022 CAC TP NOPR, DOE noted that the variable-speed 
coil-only waiver petitions addressed both air-conditioners and heat 
pumps. 87 FR 16380, 16389. Thus, DOE considered whether the coil-only 
tested combination requirement should apply to variable speed heat 
pumps and/or to single-stage and/or two-stage heat pumps. Id. DOE noted 
that coil-only heat pumps allow the heating system to provide heat 
either using the furnace or the heat pump. Id. There has been greater 
interest in such systems in recent years, since they provide heating 
with a furnace in extreme cold conditions for which a heat pump may 
have limited capacity and/or reduced efficiency.\29\ DOE proposed to 
require coil-only tested combinations for variable-speed heat pumps, 
but not for single- and two-stage heat pumps, because DOE expects that 
the representativeness of blower-coil tests would deviate more from 
coil-only tests for variable-speed systems, due to the use of a 
variable-speed indoor fan and use of an intermediate air volume rate 
used for intermediate-speed testing for variable-speed systems. Id. DOE 
argued that the test procedures for single-stage and two-stage heat 
pumps are more restrictive with regard to allowed air volume rates and 
thus performance differences between blower-coil and coil-only 
operation would be less. Id.
---------------------------------------------------------------------------

    \29\ https://www.trane.com/residential/en/resources/glossary/dual-fuel-heat-pump/ (last accessed 2/4/2022).
---------------------------------------------------------------------------

    Regarding variable-speed coil-only systems using indoor units 
manufactured by independent coil manufacturers (``ICMs''), in the March 
2022 CAC TP NOPR, DOE noted that the regulations require certification 
of the performance of every individual combination distributed in 
commerce, including both blower-coil and coil-only (see 10 CFR 
429.16(a)(1)). Id. However, a tested combination for an ICM indoor unit 
must include the least-efficient outdoor unit with which the indoor 
unit is distributed in commerce (see 10 CFR 429.6(b)(2)(i)). Id. DOE 
stated in the NOPR that it does not believe any changes are needed with 
respect to ICM certifications as the current regulations already 
encompass representing all combinations distributed in commerce, 
including noncommunicating and communicating variable-speed coil only 
systems. Id. Further, DOE noted that the least-efficient outdoor unit 
with which the indoor unit is distributed in commerce is not likely to 
be a variable-speed system, and thus the question of communicating or 
non-communicating coil-only status does not apply. Id.
    DOE received comments from multiple stakeholders regarding its 
proposals for represented values and testing requirements for VSCO CACs 
and HPs.
    Lennox agreed with DOE's proposal not to require that all variable-
speed CACs and HPs have a coil-only representation, as is required for 
single- and two-stage split air-conditioning systems. (Lennox, No. 19 
at p. 3)
    Rheem disagreed with DOE's proposal to implement differing test 
methods for communicating and non-communicating VSCO systems. (Rheem, 
No. 21 at p. 2) Rheem elaborated that even though they support the DOE 
proposal to expand the federal test procedure to account for coil-only 
variable speed systems, the exclusive distinction between communicating 
and non-communicating classifications for coil-only variable speed 
systems creates additional complexity and has the potential to add more 
test burden while reducing market flexibility. Id. Rheem stated that 
ideally there would only be one test procedure for coil-only variable 
speed systems, and preferably the one test would be the non-
communicating method, as this would likely represent the least 
efficient system that may be installed the field. Id. Rheem recommended 
that DOE reconsider the merits of implementing differing test methods 
and suggested further study by DOE to quantify the difference in 
efficiency representation between the test methods for communicating 
versus non-communicating prior to incorporating this into the final 
rule. Id.
    DOE is working to better understand the differences in performance 
between communicating and non-communicating systems but believes that 
the fundamental differences in the control architecture of the two 
approaches will lead to performance differences. For example, DOE 
expects that non-communicating VSCO systems, when subjected to an 
applied load, will likely demonstrate ``hunting'' for compressor speed, 
fan speeds, and valve positions, which would reduce the measured 
efficiency and potentially invalidate test results. For communicating 
VSCO systems, however, DOE expects that these systems will be more 
likely to include the requisite hardware and controls architecture to 
accurately and repeatably set position of modulating components during 
testing.
    Trane commented that although DOE's recommendations for variable-
speed coil-only test procedures were a good start at addressing 24V 
coil-only ratings with variable speed outdoor units, it needs to be 
expanded. (Trane, No. 10 at pp. 1-2) Trane specified that in situations 
where two-stage thermostats are paired with a two-stage airflow capable 
furnace, the proposed procedure is a reasonable rating approach, but 
that in the converse case with a single-stage thermostat or a single-
stage airflow furnace, the proposed procedure will inflate the unit 
efficiency. Id. Trane recommended that two-different `coil-only 
ratings' should be listed for such systems. Id. Trane elaborated that 
an accessory note would indicate the applicable installation (1-stage 
or 2-stage). Id. The rating

[[Page 64564]]

procedure for the 1-stage case would essentially follow the single 
capacity system rating procedures, whereas the 2-stage case would 
follow the procedure proposed by DOE in the March 2022 CAC TP NOPR. Id. 
Trane also provided two connection diagrams \30\ as examples. Id. Both 
diagrams showed connection with either a 1-stage thermostat and indoor 
unit or a 2-stage thermostat and indoor unit. Id.
---------------------------------------------------------------------------

    \30\ Trane provided examples of two Bosch systems with AHRI 
reference numbers 206395973 and 206395967 and provided a link to the 
installation instructions: https://www.bosch-thermotechnology.us/us/media/country_pool/documents/bosch_ids_bovb18_iom_10.2020.pdf.
---------------------------------------------------------------------------

    DOE notes that representations of performance for both single-stage 
and two-stage installations are not required for two-stage coil-only 
systems. The two-stage coil only test provisions in the current DOE 
test procedure are premised on the installation location having two-
stage thermostat wiring (Final Rule Technical Supporting Document, 
EERE-2014-BT-STD-0048, No. 98, p. 8-25). DOE similarly assumes the 
presence of the necessary wiring for the installation of variable-speed 
coil-only systems in two-stage configuration.
    Daikin commented that due to the nature of variable-speed CAC and 
HP, having a coil-only representation requirement for ICMs may be 
appropriate. (Daikin, No. 24 at p. 2) DOE notes that the current 
requirements in 10 CFR 429.16 already require a representation for 
every combination distributed in commerce, and hence any coil-only 
product distributed in commerce by an ICM would already be required to 
have a coil-only representation for variable-speed combinations with 
which it is distributed in commerce. The further clarification of non-
communicating VSCO combinations in this rule extends that requirement 
such that there must at least be a representation based on the non-
communicating VSCO test procedure if non-communicating combinations are 
distributed in commerce.
    Daikin and Rheem disagreed with the proposal to require the tested 
combination to be coil-only for variable-speed systems that are 
distributed in commerce in some cases with coil-only combinations. 
(Daikin, No. 24 at p. 2; Rheem, No. 21 at p. 2) Daikin claimed that a 
mandatory coil-only tested combination requirement for variable speed 
systems would burden manufacturers of such systems with additional 
testing requirements and would force lower represented values not 
indicative of variable speed performance in typical installations. 
(Daikin, No. 24 at p. 2) Daikin stated that manufacturers would still 
test a blower-coil combination if the regulations require them to test 
a coil-only combination, because of the vast majority of full-system 
installations for VS systems. Id. Although Daikin did not explain why a 
manufacturer couldn't test a coil-only combination and use an 
alternative efficiency determination method (``AEDM'') to determine the 
representative value for blower-coil systems with which the same 
outdoor unit is paired, DOE acknowledges that the wider range of air 
volume rates allowed with blower-coil testing as compared with coil-
only testing \31\ could make the use of testing (as opposed to an AEDM) 
more important in determination of an accurate representation for 
blower-coil systems than for coil-only systems. In addition, the 
Emerson comments described in the following paragraph suggest that many 
variable-speed outdoor models with blower-coil representations may be 
distributed in commerce for a small percentage of installations in 
coil-only combinations (see Emerson, No. 14 at p. 2). Although not 
explicitly mentioned in comments addressing this topic, DOE realizes 
that manufacturers may have already completed testing for many models 
in advance of the January 1, 2023, date on which appendix M1 will be 
required--requiring a coil-only representation at this late stage may 
require additional testing. Thus, DOE is partially retracting the 
proposed requirement for a coil-only tested combination for VS systems 
distributed in commerce in coil-only combinations. Specifically, DOE is 
maintaining this requirement only for non-communicating coil-only 
combinations. As already discussed, the control approach for non-
communicating systems is fundamentally different than the control 
approach for communicating systems. Hence, DOE is not convinced that a 
test using the provisions for communicating VS systems (either blower-
coil or coil-only) would provide sufficient indication of non-
communicating performance to allow accurate prediction of non-
communicating performance using an AEDM based on the communicating 
system test. Thus, DOE will not require at this time that the tested 
combination be coil-only in cases where only communicating VSCO 
combinations (and no non-communicating VSCO combinations) are 
distributed in commerce with a given outdoor unit. However, DOE may 
reconsider these decisions in a later rulemaking.
---------------------------------------------------------------------------

    \31\ As described in section III.C.2.c, VSCO systems will use at 
most two air volume rates, while blower-coil VS systems may have 
multiple air volume rates. First, there is an intermediate air 
volume rate explicitly anticipated for such systems (see appendix 
M1, section 3.1.4.3). Also, as discussed in section III.D.1, DOE is 
clarifying that air volume rate may change with outdoor air 
temperature.
---------------------------------------------------------------------------

    Emerson commented that it agreed with DOE's assessment that less 
than 5 percent of variable speed systems are installed as coil-only 
configurations today. (Emerson, No. 14 at pp. 1-2) However, Emerson 
commented that it believes that two-stage CACs currently have a 
similarly small portion of installations in a coil-only configuration, 
and elaborated that they believe that energy specifications and test 
procedures should be technology-neutral and advocated that all 
modulating technology (i.e., two or more stages) should be treated in 
the same manner regarding coil-only representation requirements. Id. 
Emerson asserted that because of the ability to install VSCO CACs with 
a non-communicating thermostat, and because coil-only installation 
percentages are similar between variable speed and two-stage CACs, the 
coil-only representation requirement should either apply for both 
technologies or for neither technology. Id. Emerson provided examples 
of variable speed CAC product literature indicating that even for 
outdoor units with communicating capability, there are instructions for 
installation in a non-communicating setup using a conventional 24V non-
communicating thermostat control.\32\ Id. Emerson also highlighted that 
in some cases, the product literature provides instructions for a non-
communicating coil-only installation but shows represented values that 
are unclear whether they are derived from a blower-coil pairing or from 
the non-communicating coil-only installation.\33\ Id. Emerson 
elaborated that this creates the possibility that variable speed 
systems are currently being installed in coil-only applications

[[Page 64565]]

for which the system representations may not be representative of 
actual performance. Id.
---------------------------------------------------------------------------

    \32\ Emerson identified the Bosch BOVB 18 split system heat pump 
with ratings as low as 15 SEER (link: https://issuu.com/boschthermotechnology/docs/bosch_ids_family?fr=sYmYyNDIwODA0Mzg) and 
the Daikin FTQ series heating and cooling systems, with SEER ratings 
from 14.8-16 SEER (link: https://backend.daikincomfort.com/docs/default-source/product-documents/light-commercial/brochures/cb-ftqducted.pdf?sfvrsn=608a2626_20&_ga=2.261207556.887080242.1653602507-1260064005.1653602507&_gl=1*1cbcmhc*_ga*MTI2MDA2NDAwNS4xNjUzNjAyNTA3*_ga_MXJ05EZJZT*MTY1MzYwMjUwNi4xLjEuMTY1MzYwMjU5OS4w).
    \33\ Emerson identified the Lennox Elite Series EL18XCV Units 
(link: https://tech.lennoxintl.com/C03e7o14l/VIu12Ch2uV/507955-01a.pdf) and the Carrier 24VNA0 Infinity Variable Speed Air 
Conditioners with Greenspeed Intelligence (link: https://esmithair.com/wp-content/uploads/2020/02/Air-Conditioners_24VNA0.pdf).
---------------------------------------------------------------------------

    In response to Emerson's comments about installation instructions 
allowing for installation of non-communicating coil-only installations 
for VS systems that presumably are tested on the basis of blower-coil 
configurations, DOE notes that 10 CFR 429.16 already requires that 
representations be provided for all combinations distributed in 
commerce. Hence, representations are required for coil-only 
combinations for any VS outdoor unit that is distributed in commerce in 
such combinations. The changes in this final rule stipulate that any 
such coil-only representation be based on whether the control system 
with which it is installed is communicating or non-communicating.
    In response to Emerson's comments that coil-only installations are 
rare also for two-stage systems, DOE notes that the comments received 
on the topic of the default fan power values for low-stage operation 
when testing two-stage coil-only systems (see section III.C.1) suggests 
otherwise. None of the comments addressed the possibility that a coil-
only configuration may not be representative of two-stage system 
installations. Further, the discussion emphasized the trends in motor 
technology of furnaces that have shipped in recent years (see, e.g., 
AHRI, No. 25 at p. 3), suggesting that the representative air movers 
for two-stage systems will in many cases be existing furnaces rather 
than the fans of blower-coils systems. Hence, in this final rule DOE 
has not removed the coil-only representation requirement for two-stage 
systems or added such a requirement for variable-speed systems.
    In summary, manufacturers will be required to represent variable-
speed ACs based on how they distribute them in commerce, which includes 
whether they are coil-only communicating, coil-only noncommunicating, 
or blower coil, as applicable to a given model of outdoor unit.
3. Space-Constrained Coil-Only CAC Ratings
a. Background
    In the March 2022 CAC TP NOPR, DOE discussed the current 
requirements for determining represented values of energy efficiency 
and capacity for CACs and HPs at Sec.  429.16(a). 87 FR 16830, 16839-
16841. This section specifies that for each model of outdoor unit of a 
split-system CAC with single-stage or two-stage compressors, 
manufacturers are required to provide represented values based on at 
least one coil-only combination that is representative of the least 
efficient combination distributed in commerce with that model of 
outdoor unit. The requirement to provide coil-only ratings for each 
basic model also applies to single split CACs designed for space-
constrained applications (``SC-CAC''). Additional blower-coil ratings 
are allowed (i.e., optional) for any applicable individual 
combinations, if distributed in commerce. 10 CFR 429.16(a).
    DOE also discussed the related waiver requests received from 
manufacturers of space-constrained split-system CACs following the 
January 2017 CAC TP Final Rule. 87 FR 16830, 16839-16841. DOE received 
petitions for test procedure waivers from National Comfort Products 
(``NCP''), AeroSys, and First Company related to the represented value 
requirements for space-constrained split-system CACs. Id. Each 
petitioner claimed that specified basic models of SC-CAC outdoor units 
listed in their respective petitions are designed and intended to be 
sold only with proprietary blower-coil indoor units equipped with high-
efficiency electronically commutated (``ECM'') fan motors, and not as a 
coil-only combination, and therefore requested exemption from the 
requirements at 10 CFR 429.16(a)(1) to provide represented values as a 
coil-only combination. (NCP, EERE-2017-BT-WAV-0030, No. 1 at p. 1; 
AeroSys, EERE-2017-BT-WAV-0042; No. 1 at p. 1; First Co., EERE-2018-BT-
WAV-0012, No. 2 at p. 1) As described in the March 2022 CAC TP NOPR, 
DOE denied First Co.'s petition, Aerosys filed for bankruptcy following 
DOE's granting them an interim waiver, and DOE granted an interim 
waiver applicable for appendix M to NCP on May 15, 2018. 87 FR 16830, 
16841.
    In the March 2022 CAC TP NOPR, DOE proposed several revisions 
related to representation requirements for space-constrained split-
system CACs. 87 FR 16830, 16840-16841. Specifically, DOE proposed to 
amend the language in the table found in 10 CFR 429.16(a)(1) to clarify 
the rating requirements pertaining to single-split CACs with single-
stage or two-stage compressors.\34\ Id. DOE also tentatively concluded 
that measuring the performance of space-constrained systems exclusively 
with high-efficiency blower-coil combinations, as requested in waiver 
petitions from NCP, AeroSys, and First Co., is not generally 
representative of field operation. Id. DOE also noted that because 
NCP's waiver petition and the prescribed alternate test procedure are 
specific to appendix M, the interim waiver will terminate on the date 
on which testing is required under appendix M1 (i.e., January 1, 2023). 
Id. DOE therefore did not propose amendments to appendix M1 to 
incorporate the interim test procedure waiver granted to NCP, and 
requested comment on these proposals. Id.
---------------------------------------------------------------------------

    \34\ DOE's proposed clarifications would require every single-
stage and two-stage outdoor unit of single-split CAC to have a 
compliant rating with a coil-only combination that is distributed in 
commerce and representative of the least efficient combination 
distributed in commerce for that particular model of outdoor unit.
---------------------------------------------------------------------------

    The Joint Advocates and Lennox supported DOE's proposal to require 
coil-only representations for all single- and two-stage single-split 
system CACs, including space-constrained systems. (Joint Advocates, No. 
18 at p. 3; Lennox, No. 19 at p. 3) Lennox elaborated on their support 
by stating that consistency in requirements across similar product 
types provides consumers with more information to properly compare 
product choices and promotes market fairness.
    In contrast with the Joint Advocates and Lennox, AHRI and NCP did 
not support DOE's proposal. (AHRI, No. 25 at pp. 2-3; NCP, No. 16 at 
pp. 2-10) AHRI and NCP criticized several aspects of DOE's proposal to 
require coil-only ratings for space-constrained CACs. Id. In general, 
AHRI and NCP critiqued the factual basis underlying DOE's assumptions 
that a coil-only rating would be most representative of real-world 
performance for space-constrained systems, and asserted that DOE must 
amend the test procedure in appendix M1 to incorporate the interim 
waiver granted to NCP. (AHRI, No. 25 at p. 3; NCP, No. 16 at p. 2) NCP 
also claimed that they would face undue burden from DOE's proposal, 
related to sunk design and testing costs and potential redesign costs 
they claim would be required to generate a compliant coil-only rating. 
(NCP, No. 16 at p. 2) AHRI elaborated by claiming that DOE did not 
provide persuasive data to justify not amending appendix M1 to specify 
testing of space-constrained split-system CACs in a manner consistent 
with NCP's waiver and that the test procedure outlined in the waiver 
produces results that more accurately reflect the performance of space-
constrained CAC systems, as opposed to a coil-only rating. (AHRI, No. 
25 at p. 3)
b. Applicability of Coil-Only Requirement
    In the March 2022 CAC TP NOPR, DOE briefly discussed some of the 
reasoning from past documents used to

[[Page 64566]]

support the coil-only representation requirement for spilt-system air 
conditioners generally. 87 FR 16830, 16847. DOE also discussed the 
applicability of the coil-only requirement for space-constrained CACs, 
specifically. 87 FR 16830, 16841. This section provides a more 
extensive discussion of the historical context to further support DOE's 
position on this matter, in light of comments on this rulemaking as 
well as historical assertions from manufacturers of space-constrained 
products that the coil-only provisions should not apply to these 
products (e.g., see First Co. comments at EERE-2016-BT-TP-0029, No. 21 
at p. 2).
    The historical application of the coil-only representation 
requirement to SC-CACs involves several changes in regulatory 
provisions for this type of product, including the provisions for 
``Through-the-Wall'' (TTW) product classes of CACs and HPs. In their 
waiver petition, and in comments in response to the March 2022 CAC TP 
NOPR, NCP refers to their models of space-constrained CACs as ``TTW'' 
products. However, while the models that were the subjects of the NCP 
waiver are physically installed through the exterior wall, the specific 
term ``through-the-wall'' no longer has regulatory meaning as a defined 
class of products. As explained in the following paragraphs, the TTW 
product class expired from DOE definitions in 2010 and is no longer 
applicable.
    In a May 2002 final rule for energy conservation standards for CACs 
and HPs, (``May 2002 CAC ECS Final Rule''), DOE established separate 
product classes of SC and TTW product classes. 67 FR 36368, 36406 (May 
23, 2002). DOE defined TTW CACs and HPs based on physical 
characteristics of the unit (i.e., limitations on cooling capacity and 
heat exchanger area), and the installation scenario (i.e., designed to 
be installed within a fixed-size opening in an external wall). 10 CFR 
430.2. The definition for TTW CACs was also limited to products 
manufactured prior to January 23, 2010. Id. In an August 2004 
rulemaking for energy conservation standards for CACs and HPs (``August 
2004 CAC ECS Final Rule''), DOE elaborated that after January 23, 2010, 
the standards for space-constrained products would apply to TTW CACs 
and HPs. 69 FR 50997, 50998 (August 17, 2004). In a June 2011 direct 
final rule (DFR) regarding energy conservation standards for 
residential furnaces and CACs/HPs (``June 2011 Furnaces & CAC ECS 
DFR'') DOE discussed the recent expiration of the through-the-wall 
product class for CACs. 76 FR 37408, 37446 (June 27, 2011). DOE noted 
that the TTW product class expired on January 23, 2010, and 
reclassified all TTW products into corresponding classes of space-
constrained CACs. Id. To further illuminate this point, DOE added a 
footnote to the energy conservation standards tables at Sec.  
430.32(c)(2) to clarify the treatment of TTW product classes. 76 FR 
37408, 37546.
    The existence of the TTW product class (and subsequent expiration 
in 2010) interacts with the coil-only representation requirements 
described by DOE in other documents. In an October 2007 test procedure 
final rule for CACs (``October 2007 CAC TP Final Rule''), DOE discussed 
the required indoor unit combinations for determination of represented 
values for CACs and HPs. 72 FR 59906, 59913-59914 (October 10, 2007). 
DOE clarified in this rule that for most classes of single-stage, 
single-split CACs the highest sales volume indoor unit would be a coil-
only indoor unit, and thus DOE's regulations required that represented 
values for these systems be determined based on a coil-only pairing. 
Id. DOE included exemptions to the coil-only representation requirement 
for certain kinds of single-stage, single-split CACs that would likely 
be distributed in commerce only with blower-coil indoor units. Id. 
These exempted product classes included mini-splits, multi-splits, and 
TTW units. Id. For each of these classes, DOE clarified in the October 
2007 CAC TP Final Rule that representations could be based on blower-
coil combinations. Id.
    In subsequent documents, DOE re-iterated the coil-only 
representation requirement and clarified the applicability to space-
constrained CACs. In a draft guidance document published August 19, 
2014 (``2014 CAC Guidance''), DOE stated that split-system CACs with 
more than one compressor stage may be tested and rated as a blower-coil 
combination only if the condensing unit is sold exclusively with 
blower-coil indoor units. EERE-2014-BT-GUID-0033-0001, p. 1. The 2014 
CAC Guidance stated that per existing regulations in the CFR, no 
provisions existed permitting use of a blower-coil for testing and 
rating a split-system central air conditioner where the condenser unit 
is also offered for sale with a coil-only indoor unit and that, 
furthermore, there was no provision in the CFR permitting the use of a 
blower-coil for testing and rating a condensing unit with a single-
speed compressor. Id. Soon thereafter, DOE published a test procedure 
final rule pertaining to CACs and HPs (``June 2016 CAC TP Final 
Rule''). 81 FR 36992 (June 8, 2016). DOE adopted language that 
explicitly required a coil-only representation requirement for single-
split single- and two-stage CACs into its provisions at 10 CFR 
429.16(a)(1), which became effective 180 days following the publication 
of the final rule (i.e., December 5, 2016). DOE also adopted these 
provisions for space-constrained split-system CACs given that they are 
subject to the same test procedures and sampling plans as non-space-
constrained single-split air conditioners. 81 FR 36992, 37002. DOE also 
adopted provisions at Sec.  429.16(b)(2) requiring that such systems be 
tested with ``the model of coil-only indoor unit that is likely to have 
the largest volume of retail sales with the particular model of indoor 
unit.'' 81 FR 36992, 37050.
    In the January 2017 CAC TP Final Rule, DOE kept the same approach 
from the June 2016 CAC TP Final Rule requiring that represented values 
for one- and two-stage single-split CACs (including space-constrained) 
must be determined based on a coil-only value representative of the 
least-efficient combination distributed in commerce with that 
particular model of outdoor unit. DOE amended the tested combination 
requirements to prevent possible conflict between the representation 
requirements and the tested combination requirements. Instead of 
requiring the ``highest sales volume'' indoor unit in the tested 
combination, the January 2017 CAC TP Final Rule required, simply, ``A 
model of coil-only indoor unit''. 82 FR 1426, 1470. This clarification 
made clear that in all instances, one- and two-stage single-split CACs 
(including space-constrained) were required to test and determine 
represented values based on a coil-only indoor unit, regardless of 
prevalence of retail sales.
    In the January 2017 CAC TP Final Rule, DOE also fielded comments 
from manufacturers of space-constrained CACs regarding the interplay of 
the TTW and space-constrained product classes with the coil-only 
representation and testing requirements. 82 FR 1426, 1461-1462. DOE 
reiterated that an exclusion for coil-only testing of space-constrained 
products was never established, and that manufacturers of space-
constrained products had always been subject to the coil-only rating 
requirement, as clarified in the June 2016 CAC TP Final Rule. Id. DOE 
also alluded to the expiration of the TTW product class, describing 
that the coil-only exclusion for TTW CACs, previously present in 10 CFR 
429.16(a)(2)(ii), would not encompass

[[Page 64567]]

the circumstances described by the commenters. Id. DOE reiterated that 
while the language being adopted in the January 2017 CAC TP Final Rule 
explicitly removed the exclusion from a coil-only testing requirement 
for TTW units sold and installed with blower-coil units--it would have 
no effect on the ratings procedures for space-constrained units (due 
the 2010 expiration of the TTW product class), which are subject to the 
same coil-only provisions as for other split system CACs. Id.
    In summary, single-split single-stage CACs, including space-
constrained CACs, have historically always been subject to a coil-only 
representation requirement, via application of the highest-sales-
volume-combination (HSVC) concept. DOE has, at multiple points, made 
this requirement more explicit in the regulatory text but has 
consistently held that space-constrained CACs were never excluded from 
this requirement. For space-constrained CACs meeting the historical 
definition of through-the-wall (TTW) products, DOE has similarly 
explained in multiple documents that this product class expired in 
January 2010 at which point TTW products were subsumed by the space-
constrained product class, which DOE explained explicitly in the 
January 2017 CAC TP Final Rule (82 FR 1426, 1462). Through these facts 
it is evident that through-the-wall space-constrained CACs, such as 
those identified in NCP's waiver petition, have been subject to the 
coil-only rating requirement at least since 2010, and the January 2017 
CAC TP Final Rule did not represent the first instance of this 
practice.
c. Other Considerations
i. Prevalence of Coil-Only Installations for Space-Constrained CACs
    In response to the March 2022 CAC TP NOPR, NCP commented that it 
does not manufacture a coil-only indoor unit that may be matched with 
the condensing units specified in their waiver, nor do they identify or 
offer any other coil-only matched system for distribution in commerce. 
(NCP, No. 16 at p.10) Additionally, AHRI and NCP questioned the 
representativeness of a coil-only rating for space-constrained 
products. Specifically, they both challenged DOE's assumption that the 
relative division of coil-only installations applies equally between 
typical CAC and space-constrained CAC. (AHRI, No. 25 at p. 2; NCP, No. 
16 at pp. 3-5) AHRI asserted that space-constrained CAC systems are 
typically installed in multi-family buildings (as opposed to single-
family homes) and claimed that coil-only installations for space-
constrained systems are significantly less common than coil-only 
installations for conventional split CACs. (AHRI, No. 25 at p. 2) AHRI 
cited DOE's determination that, in 2021, 39% of split-system CAC 
installations would be blower-coil indoor units and the remaining 61 
percent would be coil-only installations.\35\ Id. AHRI contrasted this 
with 2015 RECS microdata showing that for multi-family buildings, only 
45 percent of buildings use natural gas or other fuel source for 
heating while 55 percent of buildings use electric resistance heating. 
Id. DOE interprets AHRI`s comment to imply that space-constrained CACs 
are most typically installed in multi-family housing, and multi-family 
buildings are predominated by electric heating (which would be 
indicative of a blower-coil CAC using electric resistance heating 
elements) rather than combustion heating (which would be indicative of 
a coil-only CAC paired with a furnace). Therefore, AHRI's comment 
implies that space-constrained CACs would be represented more 
accurately by a blower-coil combination instead of a coil-only 
combination. NCP reiterated the data presented by AHRI and commented 
that coil-only installations for space-constrained systems are 
uncommon. (NCP, No. 16 at pp. 3-5)
---------------------------------------------------------------------------

    \35\ As introduced in section III.D.1.b of this rulemaking, DOE 
first discussed its assumptions regarding market penetration rates 
for various types of furnace fan motors in the December 2016 CAC ECS 
TSD (EERE-2014-BT-STD-0048-0098, page 7-16). These same proportions 
were carried through in the analysis proposed in the March 2022 CAC 
TP NOPR.
---------------------------------------------------------------------------

    DOE notes that although AHRI provided summary data regarding the 
heating source for multi-family buildings, neither AHRI nor NCP 
provided concrete data showing the relative proportion of coil-only 
installations for space-constrained CACs vs coil-only installations for 
conventional CACs. DOE finds that AHRI's inference that a higher 
proportion of electric heating in multi-family homes does not 
constitute sufficient evidence to conclude that the proportion of coil-
only installations for space-constrained systems is lower than the 
proportion for conventional systems. With respect to NCP's comment that 
they do not manufacture or specify coil-only indoor units to be paired 
with their TTW condensing units, DOE notes that the coil-only 
representation requirement is equally applicable for all single- and 
two-stage split-system CACs. This requirement accounts for the 
likelihood that CAC outdoor units may be installed as a coil-only 
configuration, even if not specified as such by the outdoor unit 
manufacturer. In this manner, the coil-only requirement provides a 
conservative estimate of performance that captures the range of likely 
installation scenarios for these products. Therefore, DOE concludes 
that an approach consistent with the January 2017 CAC TP Final Rule 
(i.e., requiring coil-only representations for all single- and two-
stage split system CACs, including space-constrained) provides more 
representative measurement of space-constrained system performance. DOE 
also acknowledges Lennox's comment stating that by continuing to 
require a coil-only representation for all types of split-system CACs, 
consumers would have better ability to compare products on the basis of 
cost-efficiency tradeoffs. (Lennox, No. 19 at p. 3)
ii. Systems Distributed in Commerce
    In the March 2022 CAC TP NOPR, DOE highlighted instances for which 
outdoor units designed for space-constrained applications are being 
distributed in commerce without a corresponding blower-coil indoor 
unit, indicating the potential for pairing a replacement outdoor unit 
with an existing indoor unit using a legacy fan that would not likely 
be comparable to the ECM fan of the blower-coil indoor unit on which 
the system rating is based. 87 FR 16830, 16841. DOE noted that the 
cited example is for sale of an NCP outdoor unit, which indicates that 
it is impossible to ensure its installation with a blower-coil indoor 
unit, as suggested by NCP's waiver petition. Id.
    AHRI and NCP challenged DOE's conclusion that NCP's space-
constrained CAC models are distributed in commerce with a coil-only 
indoor unit pairing. (AHRI, No. 25 at p. 2; NCP, No. 16 at p. 10) NCP 
stated that they do not manufacture a coil-only indoor unit that may be 
matched with their space-constrained condensers, nor do they identify 
or offer any other coil-only matched system for distribution in 
commerce. (NCP, No. 16 at p. 10) NCP also noted that in the case 
identified by DOE of an online distributor selling NCP's space-
constrained outdoor units in an unmatched pairing, this was in error 
and that NCP quickly took actions to rectify the situation. Id. NCP 
demonstrated steps they undertake to ensure that its space-constrained 
condenser units are properly sold and marketed as matching pairs with 
blower-coil indoor units and offered to provide enhanced documentation 
including a product label. Id. NCP concluded by stating that as a small 
company, it does not have the appropriate resources to police the

[[Page 64568]]

actions of distributors or installers. (NCP, No. 16 at p. 7) AHRI 
offered similar commentary, claiming that DOE made a logical leap by 
attributing the actions of a single distributor to actions taken by 
NCP, and asserted that the distributor did not follow manufacturer 
sales guidelines. (AHRI, No. 25 at p. 2)
    Regarding NCP's claim that the example provided by DOE was an 
aberration and not representative of their normal distribution 
practices, DOE has found additional evidence beyond what was presented 
in the NOPR demonstrating that NCP condensers may be distributed in 
commerce as unspecified pairings. DOE has found additional listings 
from two other distributors advertising NCP condensing units (in fact, 
the same units identified in NCP's interim waiver) being sold without a 
matched blower-coil indoor unit.\36\ Further, while DOE acknowledges 
NCP's status as a small business entity, and the potential difficulties 
with policing the activity of distributors, DOE notes that the coil-
only representation requirement for split-system one and two-stage CACs 
is designed to capture the range of installations scenarios in which 
these systems are likely to be installed. Correspondingly, the coil-
only representation requirement offers a conservative method that 
ensures that consumers would be purchasing systems that are compliant 
with national standards, even if installed in a coil-only 
configuration.
---------------------------------------------------------------------------

    \36\ DOE identified the NCPE-418-5010 condensing unit sold as a 
standalone unit at both SkipTheWarehouse and on Johnstone Supply, 
available online at: https://skipthewarehouse.com/ncpe4185010-15-ton-thru-the-wall-split-system-condensing-unit and https://www.johnstonesupply.com/product-view?pID=B61-354, respectively.
---------------------------------------------------------------------------

iii. Interaction With Energy Conservation Standards
    Notwithstanding their concerns about the representativeness of 
coil-only representations for space-constrained CACs, NCP stated that 
they have begun the process of designing and testing modifications to 
their space-constrained outdoor units that could allow certifications 
with coil-only representations (such as incorporating high-efficiency 
DC fan motors, microchannel heat exchangers and/or proprietary 
compressor developments), but that these design changes would come at a 
considerable cost increase.\37\ (NCP, No. 16 at pp. 5-7) NCP claimed 
that they utilize the most efficient components available that are 
economically justifiable and asserted that the technical constraints 
preventing the certification of its space-constrained condenser units 
as a coil-only combination have not changed since they submitted their 
original waiver petition. Id. Particularly, NCP highlighted that they 
are limited in what they can do to improve the efficiency of the units 
due to the dimensional restrictions of the space-constrained 
configuration. Id. NCP also provided data showing that even if DOE were 
to introduce a lower default fan power coefficient for coil-only CACs 
at low-stage operation (as discussed in section III.C.1 of this final 
rule), it would still be difficult to meet DOE standards. Id.
---------------------------------------------------------------------------

    \37\ On August 11, 2022, NCP submitted an enclosure to their 
earlier comment that contained new test data and design information. 
NCP claimed that they had not yet identified a combination of 
components that would allow its TTW condensing units tested with 
coil-only indoor units to reach the applicable energy conservation 
standards and capacity requirements. NCP reiterated their opinion 
that the unacceptable test results were caused by the physical 
constraints placed on space-constrained TTW condensing units. (NCP, 
No. 26 at p.2) Available online at: https://www.regulations.gov/document/EERE-2021-BT-TP-0030-0026.
---------------------------------------------------------------------------

    AHRI and NCP also claimed that DOE's decision at this stage in the 
process to terminate and discontinue the test procedure waiver for 
appendix M by not incorporating it into the M1 procedure would place 
undue burden on NCP, a small manufacturer. (AHRI, No. 25 at p. 2; NCP, 
No. 16 at pp. 9-10) AHRI stated that manufacturers have substantially 
completed testing according to appendix M1 and that NCP was in the 
process of finalizing M1 product designs and preparing for 2023 
implementation. (AHRI, No. 25 at p. 2) NCP stated that its space-
constrained condensing units are designed and intended to be paired 
with specified air handlers. (NCP, No. 16 at pp. 9-10) NCP elaborated 
that due to the new M1 testing procedures they have designed, 
prototyped, tested, and begun manufacture of a new air handler, which 
they asserted was an arduous, costly undertaking for a small business. 
Id. NCP also highlighted the challenges of simultaneously addressing 
the pending refrigerant change in 2025, which they asserted would 
require replacement of R-410a refrigerants in its outdoor units. Id. 
NCP concluded by stating that if DOE continues with the proposed 
approach of requiring coil-only representations for space-constrained 
systems tested according to appendix M1, it will require redesign of 
their space-constrained products (as previously described) and would 
substantially increase the burden and cost of testing as well as 
resource allocation for NCP. Id.
    With respect to NCP and AHRI's arguments regarding the potential 
difficulties meeting standards, DOE notes that the stringency of 
standards for such TTW products have not changed since Jan 23, 2010 
(the date when the TTW product class was subsumed by the space-
constrained product class) and they have been required to meet a 12 
SEER standard ever since. The stringency will also not be increasing 
for these products in the upcoming 2023 standards, where DOE has 
established equivalent-stringency SEER2 standards. Lennox concurred 
with DOE's finding that extending the current test procedure waivers 
for space-constrained systems is unnecessary, because adequate 
standards relief was already provided when DOE maintained the existing 
standard levels with no increase in stringency during the previous 
energy conservation standards rulemaking. (Lennox, No. 19 at pp. 3-4) 
Because DOE did not increase the stringency of standards for space-
constrained systems in the previous ECS rulemaking, manufacturers of 
space-constrained systems who were already producing space-constrained 
products compliant with standards in terms of SEER and following the 
existing representation requirements (i.e., based on a coil-only 
rating) \38\ would not incur any costs in order to comply with SEER2 
standards based on coil-only ratings. DOE also notes that in their 
comment, NCP identified several combinations of coil-only indoor units 
that were technologically capable of meeting SEER2 standard levels. 
Additionally, the topic of cost/efficiency tradeoffs for space-
constrained systems was discussed in the previous ECS rulemaking, and 
are not subject to reevaluation in the context of this rulemaking, 
which is limited to the test procedure.
---------------------------------------------------------------------------

    \38\ See October 2016 CAC ECS notification of data availability 
NODA, where DOE described its provisional translations between SEER 
and SEER2 for space-constrained products. DOE conducted a crosswalk 
for SC-CACs to account for the increased minimum external static 
pressure requirement in appendix M1 which would increase the indoor 
fan power consumption. DOE's crosswalk analysis assumed a coil-only 
rating as the starting point (i.e., for appendix M measurements), 
and a coil-only rating as the end point (i.e., for appendix M1 
measurements). 81 FR 74727, 74729-74730.
---------------------------------------------------------------------------

    d. Conclusions
    As described in preceding sections, DOE has made the following 
determinations regarding representation requirements for space-
constrained CACs:
    1. Single-split, single-stage CACs, including space-constrained 
CACs, have historically always been subject to a

[[Page 64569]]

coil-only representation requirement. DOE has clarified this 
requirement at multiple points in the regulatory text, but has 
consistently held that space-constrained CACs were never excluded from 
this requirement.
    2. For space-constrained CACs meeting the historical definition of 
through-the-wall (TTW) products, DOE has similarly explained in 
multiple documents that this product class expired in January 2010 at 
which point TTW products were subsumed by the space-constrained product 
class and became subject to the coil-only representation requirement.
    3. Based on the best available data, the coil-only representation 
requirement for split-system space-constrained CACs is representative 
of real-world installations. This determination is supported by the 
finding that, despite manufacturer efforts, space-constrained outdoor 
units are still being distributed in commerce in a manner consistent 
with coil-only installations.
    4. Space-constrained systems have been subject to a coil-only 
requirement since January 2010, and standards have remained at 
equivalent stringency since that time. Manufacturers of space-
constrained systems that have been producing compliant products would 
not incur any costs in order to comply with SEER2 standards.
    Further, DOE notes that the interim waiver granted to NCP was only 
applicable for appendix M, and NCP did not submit any waiver request 
applicable to appendix M1. As previously discussed, DOE proposed in the 
NOPR not to incorporate into appendix M1 the waiver method granted to 
NCP for appendix M. In summary, consistent with its proposals in the 
March 2022 CAC TP NOPR DOE is maintaining the requirement that space-
constrained CACs follow the existing representation requirements at 10 
CFR 429.16, including the requirement for all one- and two-stage split-
system CACs to develop represented values based on testing with a coil-
only indoor unit representative of the least efficient coil-only indoor 
unit distributed in commerce for that basic model.

D. Other Test Procedure Revisions

1. Air Volume Rate Changing With Outdoor Conditions
    In the NOPR, DOE explained that requirements for setting air volume 
rate in section 3.1.4 of appendix M1 may be in conflict with 
instructions to use air volume rates that represent a ``normal 
installation'' in section 3.2, particularly for modern blower-coil 
systems with multiple-speed or variable-speed indoor fans and control 
systems, which may change air volume rate in response to operating 
conditions such as outdoor air temperature. 87 FR 16830, 16841. To 
address this issue, DOE proposed in the March 2022 CAC TP NOPR to 
explicitly state in Step 7 of sections 3.1.4.1.1.a, 3.1.4.2.a, and 
3.1.4.3.a that, for blower-coil systems in which the indoor blower 
capacity modulation correlates with outdoor dry bulb temperature or 
sensible-to-total cooling capacity ratio, use an air volume rate that 
represents a normal operation. 87 FR 16830, 16841-16842. Also, DOE 
indicated that to ensure consistency of testing, it may be necessary 
for manufacturers to certify whether the system varies blower speeds 
with outdoor air conditions. However, certification is not being 
addressed in this rulemaking and may be addressed in a separate 
rulemaking. Id.
    In response, Lennox, Rheem and Trane commented that they support 
DOE's proposal to add clarifying language to allow fan speed and air 
volume adjustments for varying outdoor conditions that are 
representative of normal field operation, for blower-coil systems with 
multiple-speed or variable-speed indoor fans. (Lennox, No. 19 at p. 4, 
Rheem, No. 21 at p. 2, Trane, No. 10 at p. 3) Rheem further commented 
that they also support the control system capability to adjust air 
volume rate as a function of outdoor air temperature, allowing such air 
volume rate variation during testing. (Rheem, No. 21 at pp. 2-3) In 
order to make the procedure more representative of field conditions, 
Rheem suggested that external static pressure should change in relation 
to full stage air flow by using the fan affinity laws, similar to 
external static adjustments for multi-stage equipment. Id. 
Additionally, Rheem suggested that DOE's proposal to add clarifying 
language for blower speed variation should apply to section 
3.1.4.4.3.a, instead of section 3.1.4.3.a. Id. Trane pointed out that 
they have products that vary the fan speed based on various conditions 
such as outdoor ambient and stated that the proposed change is needed 
to clear up the discrepancy in procedures. (Trane, No. 10 at p. 3) They 
stated that there are several reasons why airflow may be varied from a 
nominal setting at different conditions; for example, to optimize 
sensible heat ratio and comfort, to maintain consistent heating supply 
air temperatures, and to maximize system efficiency. Id.
    In response to Rheem's comment about external static adjustments, 
DOE believes that the proposed regulatory language already addresses 
this factor, in particular the language: ``and calculate the target 
minimum external static pressure as described in section 3.1.4.2 of 
this appendix,'' which is included in Step 7 where the proposed 
revisions were made. The adjustment of external static pressure 
described in section 3.1.4.2 specifies that pressure varies as the 
square of the air flow, consistent with the fan affinity laws mentioned 
by Rheem. Hence, DOE is finalizing the revision without additional 
changes in regard to instructions regarding external static pressure. 
Also, in response to Rheem, DOE acknowledges that the NOPR preamble 
incorrectly cited section 3.1.4.3.a instead of 3.1.4.4.3.a.--the change 
was proposed and is finalized in section 3.1.4.4.3.a.
    NEEA pointed out that DOE's proposal does not require certification 
of the fan speeds that represent ``normal'' operation for the different 
test points, and expressed concern that this approach will allow 
products to be tested more favorably without confirmation that the 
testing represents how products operate in the field. (NEEA, No. 23 at 
p. 2) NEEA recommended that DOE verify blower speed variation with a 
load-based test procedure using native controls of the system. Id.
    As previously stated, certification corresponding to the test 
procedure changes are not being addressed in this final rule but may be 
considered in a separate rulemaking. Regarding NEEA's recommendation 
for a test procedure requiring native controls, DOE notes that this 
test procedure rulemaking was initiated as a quick fix of a limited set 
of known issues, and that more comprehensive revisions to address 
native controls may be considered in a future rulemaking that would 
satisfy the 7-year lookback requirements. See further discussion in 
section III.B of this document.
    Based on the comments received, DOE is finalizing the provisions 
regarding variation of indoor air volume rate by adopting the 
clarifying language to Step 7 of sections 3.1.4.1.1.a, 3.1.4.2.a, and 
3.1.4.4.3.a, as proposed.
2. Wet Bulb Temperature for H4 5 [deg]F Heating Tests
    Appendix M1 specifies required and optional heating mode test 
conditions for heat pumps, designated as ``H'' conditions. See Tables 
11 through 15 of appendix M1. Appendix M1 provides for conducting 
optional ``H4'' heating tests at a 5 [deg]F outdoor ambient dry-bulb 
temperature and, at a maximum, a 3 [deg]F

[[Page 64570]]

outdoor wet-bulb temperature.\39\ The 3 [deg]F wet bulb condition 
represents an extremely dry air condition, which may be difficult to 
attain and maintain due to issues with infiltration and ground moisture 
passing through the floor in some laboratory setups. Consequently, in 
the March 2022 CAC TP NOPR, DOE proposed to amend the wet bulb test 
condition for all H4 tests to be 4 [deg]F maximum instead of the 
current condition of 3 [deg]F maximum. 87 FR 16830, 16842.
---------------------------------------------------------------------------

    \39\ The tests at this condition are optional for heat pumps, 
except for Triple-Capacity Northern heat pumps.
---------------------------------------------------------------------------

    In response, Carrier, Daikin, Lennox, Nortek, NYSERDA, and Rheem 
commented that they all support DOE's proposal to increase the wet bulb 
test condition to 4 [deg]F maximum from the 3 [deg]F maximum for H4 
tests. (Carrier, No. 15 at p. 1, Daikin, No. 24 at p. 2, Lennox, No. 19 
at p. 4, Nortek, No. 13 at p. 3, NYSERDA, No. 17 at p. 2, Rheem, No. 21 
at p. 3) Carrier stated that increasing the wet bulb test condition in 
the H4 test will reduce the test burden, and Lennox further asserted 
that conducting the H4 tests previously in various manufacturer 
laboratories has proven to be overly burdensome for the variety of 
reasons DOE cites in the CAC TP NOPR at 87 FR 16842. (Carrier, No. 15 
at p. 1, Lennox, No. 19 at p. 4) Carrier and Lennox commented that 
increasing the maximum wet bulb temperature for the H4 test will 
significantly reduce manufacturer test burden. Id. Lennox commented 
that this will also help avoid additional capital investments in lab 
facilities for specialized equipment to attain the wet bulb requirement 
of 3 [deg]F and this relief will allow more test facilities to be 
capable of validating performance at low ambient conditions while 
maintaining sufficiently low humidity conditions to provide reasonable 
test results. (Lennox, No. 19 at p. 4) Nortek also commented that 
increasing the wet bulb temperature on the H4 test from 3 [deg]F to 4 
[deg]F will reduce their test burden by reducing the time required to 
remove moisture in achieving the wet bulb temperature test point. 
(Nortek, No. 13 at p. 3) NYSERDA commented that the proposed amendment 
of the wet bulb temperature conditions for the H4, H42, or 
H43 heating tests to a 4 [deg]F maximum temperature will 
make the current optional cold temperature test easier to reliably 
replicate and should improve understanding of system performance at 
cold temperatures for more basic models being distributed in commerce. 
(NYSERDA, No. 17 at p. 2)
    Based on the discussion presented in the March 2022 CAC TP NOPR and 
given the general support of the proposals by commenters, DOE is 
finalizing its amendment and increasing the wet bulb test condition to 
a maximum of 4 [deg]F for H4 tests.
3. Hierarchy of Manufacturer Installation Instructions
    Instructions for installation of CAC/HP products can take multiple 
forms, including documents shipped with the product, labels affixed to 
the outdoor unit and/or indoor unit, and online documents.
    Section 2(A) of appendix M1 provides requirements regarding the 
installation instructions to be used and their order of precedence 
(i.e., installation instruction hierarchy) for variable refrigerant 
flow (``VRF'') multi-split systems. Section 2(A) specifies that 
installation instructions that appear in the labels applied to the unit 
take precedence over installation instructions that are shipped with 
the unit. Further, Section 2(A) specifies that the term 
``manufacturer's installation instructions'' does not include online 
manuals. Appendix M1 does not specify installation instruction 
hierarchy for any other types of CAC/HP products.
    Throughout appendix M1, references to manufacturer's installation 
instructions are made regarding refrigerant charging requirements 
(section 2.2.5), installation of an air supply plenum adapter accessory 
for testing small-duct, high-velocity systems (section 2.4.1.c), and 
control circuit connections between the furnace and the outdoor unit 
for coil-only systems (section 3.13.1.a).
    DOE notes that it initially proposed in a supplemental NOPR 
published November 9, 2015 (``November 2015 SNOPR'') that the hierarchy 
of installation instructions be located in proposed section 2.2.5.1 of 
appendix M1, which pertains to refrigerant charging requirements. See 
80 FR 69278, 69350.\40\ However, as finalized in the June 2016 CAC TP 
Final Rule, the installation instruction hierarchy provision was 
located within section 2(A) of appendix M1, and therefore applies only 
to testing of VRF multi-split systems. 81 FR 36992, 37060. The June 
2016 CAC TP Final Rule did not provide a discussion of this change.
---------------------------------------------------------------------------

    \40\ DOE also notes that as initially proposed, installation 
instructions that are shipped with the unit were to take precedence 
over installation instructions that appear in the labels applied to 
the unit, but this hierarchy was reversed in the final rule. 81 FR 
36992, 37060.
---------------------------------------------------------------------------

    The requirements regarding installation instruction would be 
equally applicable to classes of CAC/HP other than VRF multi-split 
systems. As noted, manufacturer's installation instructions are 
referenced in a number of provisions in appendix M1. Therefore, in the 
March 2022 CAC TP NOPR, DOE proposed to add in section 2(B) of appendix 
M1, ``Testing Overview and Conditions for Systems Other than VRF,'' the 
same requirements associated with installation instructions that are in 
section 2(A), i.e., what instructions can be used and what instructions 
take precedence. 87 FR 16830, 16842. Doe noted that this proposal would 
align the approach for all classes of CAC/HP with the current approach 
for VRF CAC. Id.
    Lennox and Rheem commented that they support DOE's proposal for 
aligning the approach regarding installation instruction precedence for 
all classes of CAC/HP with the current approach of VRF AC. (Lennox, No. 
19 at p. 4, Rheem, No. 21 at p. 3) Rheem further suggested that for 
clarity in the final rule, DOE should clearly specify whether a sticker 
on the unit takes precedence over installation instructions, 
particularly where use of the installation instructions is referenced 
in the appendix M1 test procedure (Rheem, No. 21 at p. 3). 
Additionally, Rheem stated that DOE also specifies a Section 2(B) will 
be added to appendix M1 to 10 CFR part 430. Rheem points out that 
Section 2(B) already exists in the test procedure, and therefore DOE 
should add a section 2(C) to capture these changes.\41\ Id.
---------------------------------------------------------------------------

    \41\ In the May 2022 CAC TP NOPR, DOE had stated that they will 
add instructions to the already existing Section 2(B), and not that 
a new section is needed. Hence, DOE will not add a Section 2(C), as 
suggested by Rheem.
---------------------------------------------------------------------------

    In response to Rheem's comment regarding addition of section 2(B) 
of appendix M1, DOE notes that it indicated that the additional 
requirements regarding installation instructions would be inserted ``in 
section 2(B),'' not that a new section 2(B) would be added. In response 
to the comment about clarifying whether a sticker on the unit takes 
precedence over installation instructions, DOE believes that the 
language proposed for section 2(B), ``Installation instructions that 
appear in the labels applied to the unit shall take precedence over 
installation instructions that come packaged with the unit,'' 
sufficiently clarifies this point. Specifically, ``installation 
instructions'' does extend to installation instructions that appear on 
the labels applied to the unit, and that such installation instructions 
take precedence over installation instructions that are not applied to 
the unit.

[[Page 64571]]

    Trane commented that even though they agreed with hierarchy 
proposed by DOE, they raised a concern that that some combinations of 
indoor units require unique charging instructions, as opposed to the 
typical instructions, i.e., subcooling target, listed on outdoor unit 
labels. (Trane, No. 10 at p. 3) They cited the variations of indoor 
internal coil volume with various matched pairs as the reason for this. 
Hence, Trane suggested that outdoor nameplates should have a footnote 
referring the installer to the indoor product instructions for any 
exception, unless otherwise noted. Id.
    In response to Trane's comment, DOE agrees that there may be 
circumstances in which the very different design details of multiple 
indoor units paired with the same outdoor unit could affect the optimum 
installation approach. In such cases, the manufacturer has the 
discretion to indicate in the outdoor unit installation instructions 
that specific instructions provided with indoor units be followed. Such 
an approach would not be contrary to the established precedence of the 
outdoor unit's installation instructions and would not be contrary to 
the proposed appendix M1 requirements, as long as the instructions used 
are not online instructions. DOE does not believe that appendix M1 
should be modified to specifically explain this possibility.
    Hence, DOE is adding the installation instruction hierarchy to 
appendix M1 section 2(B) as proposed.
4. Adjusting Airflow Measurement Apparatus To Achieve Desired SCFM at 
Part-Load Conditions
    Sections 3.1.4.1.1, 3.1.4.2, and 3.1.4.4.3 of appendix M1 each 
specify seven steps for achieving the correct air volume rate to be 
used for testing (cooling full-load air volume rate, cooling minimum 
air volume rate, and heating full-load air volume rate, respectively). 
Each of these sections indicates that the measured air volume rate when 
adjustments are complete should be used for all tests that call for the 
same nominal air volume rate, i.e., cooling full-load, cooling minimum, 
or heating full-load air volume rate, using the final fan speed or 
control settings. However, when operating at different test conditions, 
differences in air density and/or loading of condensate on the indoor 
coil may lead to different measured air volume rates.\42\ None of the 
section 3.1.4.1.1, 3.1.4.2, or 3.1.4.4.3 of appendix M1 indicate what 
adjustments are allowed or required to obtain the same air volume rate 
for different operating conditions. In order to clarify how to achieve 
the same air volume rates for different operating conditions, DOE 
proposed to explicitly require that the airflow measurement apparatus 
fan be adjusted if needed to maintain a constant air volume rate for 
all tests using the same nominal air volume rate. Similarly, the 
section would explicitly state that the speed and settings of the fan 
of the unit under test are not to be adjusted. 87 FR 16830, 16843 
(March 24, 2022).
---------------------------------------------------------------------------

    \42\ When operating in cooling mode, water vapor in the return 
air may condense and collect and flow down the coil into the indoor 
unit's drain pan. This removal of water vapor is called 
dehumidification--it occurs only in cooling mode and its magnitude 
depends on the test conditions.
---------------------------------------------------------------------------

    In response, Lennox commented that they support DOE's proposals to 
add more specific direction to step 7 of sections 3.1.4.1.1, 3.1.4.2, 
and 3.1.4.4.3, as proposed. (Lennox, No.19 at p.4) Rheem commented that 
although they agree that the proposed changes may assist in the 
repeatability of certification tests, they disagree that DOE's 
proposals would be more representative than the current test procedure. 
(Rheem, No. 21 at p. 3) Rheem stated that once a ducted CAC/HP is 
installed in a consumer's home, the airflow and external static 
pressure will change with conditions, as reflected in the current test 
procedure. Id. Rheem noted that in the discussion under III.C.1 of the 
NOPR, DOE proposed to allow the air volume rate to change if the native 
controls of the system modulate indoor blower capacity. Rheem 
recommended that DOE add language to clarify that this allowance to 
adjust the airflow measurement apparatus only applies to systems that 
do not modulate indoor blower capacity. Id.
    DOE does not agree with Rheem's comment suggesting that the current 
test procedure does not allow adjustment of the airflow measurement 
apparatus fan. Specifically, the words, ``use the final speed or 
control settings'' is not clear regarding whether this applies to the 
unit under test, the code tester, or both. DOE notes that by not 
specifically precluding adjustment of the code tester fan, the current 
Federal test procedure does not fully specify the allowable fan 
adjustments, leaving open the possibility for clarification.
    In response to Rheem's comment regarding clarifying language, DOE 
notes that the proposed additions indicate that the final indoor fan 
speed or control settings of the unit under test must be used for all 
tests that use the same nominal air volume rate (e.g., cooling full-
load air volume rate), and that the fan of the airflow measurement 
apparatus should be adjusted if needed to obtain the same air volume 
rate (in scfm), unless the system modulates the indoor blower speed for 
different outdoor conditions or to adjust the sensible to total heat 
ratio. DOE considers this text is sufficiently clear that the 
instructions apply to systems that do not modulate indoor blower 
capacity. Further, DOE points out that adjustment of the airflow 
measurement apparatus would very likely be required for systems that do 
modulate the indoor blower capacity, to maintain the relationship 
between air volume rate and external static pressure, as required by 
section 3.1.4.2 of appendix M1.
    Hence, DOE is finalizing the changes to step 7 of the requirements 
for setting air volume rate as proposed.
5. Revision of Equations Representing Full-Speed Variable-Speed Heat 
Pump Operation at and Above 45 [deg]F Ambient Temperature
    In a variable speed system, the compressor's actual speed at its 
full-load condition may change as the outdoor temperature changes. 
While the compressor speed at full speed may differ at different 
outdoor temperatures, accuracy of predictions using the test results 
from two temperature conditions to calculate the performance for a 
third temperature condition is maximized when the same compressor speed 
is used for the tests at the two different ambient temperature 
conditions (see, e.g., 81 FR 58164, 58178 (August 24, 2016)).
    For calculation of full-speed compressor heating mode performance 
in the temperature ranges less than 17 [deg]F and greater than or equal 
to 45 [deg]F, the test procedure determines performance based on the 
H32 and H12 tests, which are conducted at 17 
[deg]F and 47 [deg]F, respectively (see appendix M1, sections 4.2.4.c, 
which refers to equations 4.2.2-3 and 4.2.2-4 in Section 4.2.2). As 
indicated in appendix M1 in the Table 14 footnotes, the H12 
test is run with the compressor speed that represents normal operation 
at 17 [deg]F conditions. However, for many variable-speed heat pumps, 
this is a higher compressor speed than would be normal for operation at 
47 [deg]F conditions.
    The H1N test represents normal 47 [deg]F operation, as 
indicated in the Table 14 footnotes. For heat pumps with different 
normal speeds for 17 [deg]F and 47 [deg]F conditions, the full-speed 
compressor performance equation is not appropriately representative for 
temperatures greater than or equal to 45 [deg]F. For example, at 47 
[deg]F, the equation would indicate that the capacity is equal to the 
H12 capacity, even though the H1N test is 
specifically intended to represent capacity at 47 [deg]F. To rectify

[[Page 64572]]

this issue, DOE proposed in the March 2022 CAC TP NOPR to amend the 
portion of the equations representing performance in conditions warmer 
than 45 [deg]F. 87 FR 16830, 16843. Specifically, DOE proposed that the 
capacity equation for this temperature range would be multiplied by the 
ratio of the capacities of the H1N and H12 tests. 
Id. Similarly, DOE proposed that the power input equation for this 
range would be multiplied by the ratio of the power inputs measured in 
the H1N and H12 tests. Id. DOE noted that this 
would change the calculated capacity and power input for the range of 
temperature above 45 [deg]F to be consistent with the compressor speed 
of the H1N test (which is intended to represent performance 
in this range), rather than with the compressor speed of the 
H32 test, which is conducted in a 17 [deg]F ambient 
temperature. Id.
    In response, Lennox supported DOE's proposed change to the full-
capacity performance equations for variable speed heat pumps in the 
ambient temperature range above 45 [deg]F. (Lennox, No. 19 at p. 5) 
Rheem recommended that DOE does not make the proposed changes. (Rheem, 
No. 21 at p. 4) Rheem contended that the proposal to modify the 
capacity and power equations above 45 [deg]F would not have significant 
effect on heat pump HSPF2 calculations, since variable speed 
applications would likely operate in low stage during low building load 
conditions. Rheem questioned the value of adding complexity to variable 
speed HSPF2 calculations if the change will not have meaningful effect 
on the results and recommends that DOE not change the current 
calculation method for HSPF2 of variable speed heat pumps. (Rheem, No. 
21 at pp. 3-4) DOE considers that the proposed calculation changes 
(i.e., applying a simple ratio coefficient) does not represent any 
significant increase in complexity compared to the overall scale of 
test procedure calculations and that it is important to provide for a 
more accurate calculation of HSPF2, even if the impact on the 
calculated HSPF2 value is minimal. Therefore, DOE is finalizing its 
proposed approach in this final rule.
6. Calculations for Triple-Capacity Northern Heat Pumps
    Section 4.2.6 of appendix M1 includes additional steps for 
calculating HSPF2 of a heat pump having a triple-capacity compressor. 
Heat pumps with triple-capacity compressors respond to building heating 
load by operating at low (k=1), high (k=2), or booster (k=3) capacity 
or by cycling on and off at one or more of those stages. Section 
4.2.6.5 covers the scenario where the heat pump alternates between high 
(k=2) and booster (k=3) compressor capacity to satisfy the building 
load. In this scenario, the total electrical power consumption is 
determined by calculating the fraction of time the system spends 
operating in the high and booster stage, respectively, and then 
weighting the steady-state power consumption at each operating state 
accordingly. Section 4.2.6.5 gives equations for calculating the 
fraction of load addressed by the high compressor stage, denoted as 
``X\k=2\(Tj)'', as well as the fraction of load addressed by 
the booster compressor stage ``X\k=3\(Tj)''. These 
proportions should, by definition, be complementary because the system 
is either operating in high compressor stage or boost compressor stage. 
However, the equation for the booster capacity load factor 
``X\k=3\(Tj)'' is erroneously set equal to the high-capacity 
load factor ``X\k=2\(Tj)'' as opposed to the complementary 
value ``1 X\k=2\(Tj).'' Therefore, DOE proposed to correct 
the booster capacity load factor equation to be defined as 
X\k=3\(Tj) = 1-X\k=2\(Tj). DOE did not receive 
any comments in response to its proposal, and is therefore finalizing 
its proposed approach in this final rule.
7. Heating Nominal Air Volume Rate for Variable-Speed Heat Pumps
    Appendix M1 includes procedures for calculating the heating 
capacity and power input for variable-speed heat pumps at various test 
conditions. The H1N test is used to calculate the nominal 
heating capacity of the system at 47 [deg]F ambient temperature, 
whereas the H12 test is used to calculate maximum heating 
capacity at 47 [deg]F and the H11 test is used to calculate 
minimum heating capacity at 47 [deg]F. Section 3.1.4.7 of appendix M1 
requires that manufacturers must specify a heating nominal air volume 
rate for each variable-speed heat pump system and must provide 
instructions for setting the fan speed or controls. The heating full-
load air volume rate is defined in section 3.1.4.4 of appendix M1, 
which ties the heating full-load air volume rate to the cooling full-
load air volume rate and denotes static pressure requirements. However, 
in Table 14 to appendix M1 (which specifies heating mode test 
conditions for units having a variable-speed compressor), the 
H1N test (used for calculating nominal heating capacity at 
47 [deg]F) is erroneously specified as using the ``Heating Full-load'' 
air volume rate instead of the heating nominal air volume rate. Because 
the H1N test is intended to represent nominal heating 
capacity, DOE is amending Table 14 to specify the ``heating nominal air 
volume rate'' as defined in section 3.1.4.7 of appendix M1 as opposed 
to the ``heating full-load air volume rate''. As discussed in section 
III.C.2 of this final rule, DOE is also amending the test provisions 
for variable-speed compressor systems with coil-only indoor units. The 
amendments mentioned in this section only apply to variable-speed 
systems equipped with blower-coil indoor units, while variable-speed 
coil-only systems would be required to test using the heating full-load 
air volume rate at the H1N test condition.
    DOE did not receive any comments in response to this issue in the 
March 2022 CAC TP NOPR and is finalizing its proposal to specify 
heating nominal air volume rate as the air volume rate to be used for 
the H1N heating test for variable-speed heat pumps.
8. Clarifications for HSPF2 Calculation
    Section 4.2 of appendix M1 contains methodologies for calculating 
HSPF2 for all heat pumps. DOE has identified an instance where 
additional instruction may be warranted to make clear the calculation 
procedures across different types of heat pump systems. In the March 
2022 CAC TP NOPR, DOE proposed to clarify the appropriate slope 
adjustment factor to be used in the calculation for building heating 
load (Equation 4.2-2). 87 FR 16830, 16844.
    As written, Equation 4.2-2 refers to the heating load line slope 
adjustment factor ``C'', which varies by climate region according to 
Table 20. However, Table 20 includes both the ``C'' factor as well as a 
factor denoted ``CVS''--the variable-speed slope factor, 
which includes different coefficients that impact calculation of HSPF2. 
CVS is not explicitly referenced in the definitions 
surrounding Equation 4.2-2, therefore DOE proposed to amend the 
language of that paragraph to indicate that the slope adjustment factor 
``C'' should be used when calculating building heating load except for 
variable-speed compressor systems, where the variable-speed slope 
adjustment factor ``CVS'' should be used instead. Id.
    DOE did not receive any comments regarding this proposal and is 
thus adopting its proposal to clarify the calculation process for 
heating load line slope factor as it pertains to variable-speed heat 
pumps.
9. Distinguishing Central Air Conditioners and Heat Pumps From 
Commercial Equipment
    EPCA defines ``industrial equipment'' as equipment of a type which, 
among other requirements, is not a covered product under section 
6291(a)(2), i.e.,

[[Page 64573]]

not a covered consumer product. (42 U.S.C.6311(2)(A)) Small, large, and 
very large commercial package air conditioning and heating equipment 
are included as types of covered industrial equipment. (42 
U.S.C.6311(1)(B,C,D))
    EPCA defines ``central air conditioner'' as a product, other than a 
packaged terminal air conditioner, which is powered by single phase 
electric current, is air-cooled, is rated below 65,000 Btu per hour, is 
not contained within the same cabinet as a furnace the rated capacity 
of which is above 225,000 Btu per hour and is a heat pump or a cooling 
only unit. (42 U.S.C. 6291(21)) DOE understands that there are basic 
models on the market that meet the central air conditioner definition 
but are exclusively distributed in commerce for commercial and 
industrial applications. In DOE's view, there are certain types of 
equipment that meet the EPCA definition of CAC but that EPCA did not 
intend for DOE to regulate as consumer products. To clarify that any 
such model is not a central air conditioner, DOE proposed in the March 
2022 CAC TP NOPR to revise the central air conditioner definition so 
that it explicitly excludes these equipment categories, similar to the 
way the original EPCA definition excludes packaged terminal air 
conditioners and packaged terminal heat pumps. The exclusion for 
single-package vertical air-conditioners and heat pumps would refer 
specifically to those models that could be confused with central air 
conditioners, i.e., those that are single-phase with capacity less than 
65,000 Btu/h, for which the test procedure notice of proposed 
rulemaking for single-package vertical air conditioners and heat pumps 
has proposed new definitions. 87 FR 2490, 2518 (January 14, 2022).
    DOE emphasizes that the exclusion from the central air conditioner 
definition for a given model depends on whether it meets the definition 
for one of the excluded categories. For example, a model must meet the 
packaged terminal air conditioner definition in 10 CFR 431.92 to be 
considered to be a packaged terminal air conditioner. If such a model 
had both characteristics listed in the central air conditioner 
definition and similarities to packaged terminal air conditioners, but 
was not ``intended for mounting through the wall,'' it would be missing 
a key characteristic of the packaged terminal air conditioner 
definition. Unless it met the definition for one of the other 
categories proposed to be excluded, it would be considered a central 
air conditioner and covered under the applicable standards and test 
procedures in part 430 irrespective of whether it gets installed in a 
consumer or commercial building.
    DOE did not receive any comments in response to its proposed 
clarification of the definition of central air conditioners and heat 
pumps at 10 CFR 430.2 to exclude other similar product categories for 
consideration of coverage. Therefore, DOE is finalizing its proposals 
from the NOPR without amendment in this final rule.
10. Additional Test Procedure Revisions
    On May 8, 2019, AHRI submitted a comment responding to the notice 
of proposed rulemaking to revise and adopt procedures, interpretations, 
and policies for consideration of new or revised energy conservation 
standards (2020 Process Rule NOPR, 84 FR 3910, Feb. 13, 2019). The 
comment included as Exhibit 2 a ``List of Errors Found in appendix M 
and appendix M1'' (``AHRI Exhibit 2''). (EERE-2017-BT-STD-0062-0117 at 
pp. 23-24) Many of the errors pointed out by AHRI regard typographical 
errors in appendices M and M1. DOE published a correcting amendment to 
appendices M and M1 on December 2, 2021 (``December 2021 Correcting 
Amendment''). 86 FR 68389. The December 2021 Correcting Amendment 
addressed some of the ``Errors'' identified in AHRI Exhibit 2, but not 
all of them. In the March 2022 CAC TP NOPR, DOE proposed to address 
additional ``Errors'' identified in AHRI Exhibit 2, discussed in the 
following sections to improve accuracy and representativeness of the 
test procedures. 87 FR 16830, 16845.
a. Revisions Specific to Appendix M
    AHRI's comment identified three areas of appendix M where they 
requested changes. (AHRI Exhibit 2, EERE-2017-BT-STD-0062-0117 at pp. 
23-24) These are detailed in Table III-4. Additionally, DOE identified 
one transcription error in the December 2021 Correcting Amendment 
related to changes made in section 3.6.4 of appendix M. DOE is making 
corresponding revisions in this final rule to correct that 
transcription error.

                                Table III-4--AHRI-Identified Errors to Appendix M
----------------------------------------------------------------------------------------------------------------
                                      Original appendix M                                Proposed change in the
             Section                        language            AHRI comment summary     March 2022 CAC TP NOPR
----------------------------------------------------------------------------------------------------------------
1.2..............................  Nominal cooling capacity   The H1N test is required  Remove the ``Optional
                                    is approximate to the      in section 3.6.4, and     H1N test'' and replace
                                    air conditioner cooling    section 3.6.4             the ``H12'' with
                                    capacity tested at A or    designates the H1N        ``H1N''
                                    A2 condition. Nominal      test--not the H12 test.
                                    heating capacity is
                                    approximate to the heat
                                    pump heating capacity
                                    tested in H12 test (or
                                    the optional H1N test).
4.1.4.2..........................  A = EER \k=1\(T) - B * T - The EER\k=1\(Tj) should   Revise the formula to
                                     C * T2\2\.                be EER\k=2\(Tj) because   implement this change
                                                               the coefficient ``A''     to EER\k=2\(Tj).
                                                               only utilizes the
                                                               maximum speed
                                                               temperature, T2.
4.2.c............................  For a variable-speed heat  2017 and later versions   Accurately implement the
                                    pump, Qh\k\(47) =          of appendix M use         change intended by the
                                    Qh\k=N\(47), the space     H\k=2\calc for all        December 2021
                                    heating capacity           conditions, as            Correcting Amendment.
                                    determined from the H1N    explained in 3.6.4.
                                    test.                      This should not be an
                                                               exception for the rest
                                                               of the calculations.
----------------------------------------------------------------------------------------------------------------

    The following sections discuss changes to the language of appendix 
M that DOE believes will improve clarity regarding how tests and 
calculations are to be conducted to determine capacity levels and 
efficiency metrics to address the topics identified in AHRI's comment.
i. Definition of Nominal Capacity
    AHRI commented that the description of nominal heating capacity 
within the definition for ``nominal capacity'' in

[[Page 64574]]

section 1.2 of appendix M incorrectly references the H1N 
test as ``optional.'' AHRI claimed that, on the contrary, the 
H1N test is required for heat pumps. (AHRI Exhibit 2, EERE-
2017-BT-STD-0062-0117 at pp. 23-24) DOE agrees with the AHRI comment, 
since section 3.6.4, ``Tests for a Heat Pump Having a Variable-Speed 
Compressor,'' requires the H1N test. Therefore, DOE proposed 
in the March 2022 CAC TP NOPR to revise the definition of ``nominal 
capacity'' to remove the references to the H12 test in its 
entirety to avoid confusion. 87 FR 16830, 16845.
    In response to the NOPR proposal, the CA IOUs commented that by 
making this reference to the H1N test, DOE is making the 
definition inapplicable to systems with single-speed and two-capacity 
compressors. (CA IOUs, No. 20 at pp.1-2) The CA IOUs proposed the 
following definition, so that it may be applicable to single-stage and 
two-stage heat pumps (additions in italics, deletions in [brackets]):
    Nominal capacity means ``the capacity that is claimed by the 
manufacturer on the product name plate. Nominal cooling capacity is 
approximate to the air conditioner cooling capacity tested at A or 
A2 condition. Nominal heating capacity is approximate to the 
heat pump heating capacity tested in the H1 or H12 test for 
units that have a single-speed compressor, the H12 test for units that 
have a two-capacity compressor or are a triple-capacity northern heat 
pump,\43\ or [(or the optional H1N test).] the H1N test for 
units that have a variable-speed compressor.'' Id.
---------------------------------------------------------------------------

    \43\ Appendix M1, section 1.2, defines ``triple-capacity, 
northern heat pump'' as a heat pump that provides two stages of 
cooling and three stages of heating. The two common stages for both 
the cooling and heating modes are the low-capacity stage and the 
high-capacity stage. The additional heating mode stage is the 
booster capacity stage, which offers the highest heating capacity 
output for a given set of ambient operating conditions.
---------------------------------------------------------------------------

    DOE notes that the term nominal heating capacity is only used to 
specify the heating capacity for the H1N test for variable-
speed systems. Additionally, the term nominal capacity is not required 
for certification of CAC/HPs. Hence, DOE is not revising the definition 
as suggested by the CA IOUs and DOE is instead finalizing the 
definition as proposed in the March 2022 CAC TP NOPR.
ii. Revising Energy Efficiency Ratio Equation at Intermediate 
Compressor Speed
    In section 4.1.4.2 of appendix M, there are a series of equations 
used to calculate EERk=i(Tj), the steady-state 
energy efficiency ratio of the test unit when operating at an 
intermediate compressor speed (k=i) for outdoor temperature 
Tj. This value is calculated using a quadratic equation: 
EERk=i(Tj) = A + B*Tj + 
C*Tj\2\. These coefficients (A, B and C) are calculated by 
their own respective formulae.
    AHRI commented that the formula for the ``A'' coefficient has an 
error. Specifically, EERk=1(T2) in the equation 
should be EERk=2(T2) because the coefficient 
``A'' only utilizes maximum-speed temperature T2. (AHRI 
Exhibit 2, EERE-2017-BT-STD-0062-0117 at pp. 23-24) In the March 2022 
CAC TP NOPR, DOE proposed to revise this calculation such that it uses 
the intended ``k=2''. 87 FR 16830, 16845. The use of ``k=2'' is 
supported both by its appearance in ASHRAE 116-2010, ``Methods for 
Testing for Rating Seasonal Efficiency of Unitary Air Conditioners and 
Heat Pumps'' (see page 25), and also in the DOE test procedure final 
rule that first established test methods for variable-speed systems. 49 
FR 8304, 8316 (March 14, 1987).
    DOE did not receive any comments in response to this proposed 
correction and is therefore finalizing its proposed approach in this 
final rule.
iii. Clarification of Compressor Speed Limits in Heating Tests for Heat 
Pumps Having a Variable-Speed Compressor
    In the December 2021 Correcting Amendment, DOE discussed 
corrections to the compressor speed limitations for the H1N 
heating mode test for both appendices M and M1. 86 FR 68389, 68390. 
However, when setting out the correcting language in the amendatory 
instruction for appendix M, the instructions erroneously directed to 
revise the fifth sentence of paragraph a. to section 3.6.4, when the 
instructions were intended to revise the seventh sentence of the same 
paragraph. As currently printed, the text in paragraph a. of section 
3.6.4 to appendix M includes two sentences starting with ``for a 
cooling/heating heat pump . . .'' that give conflicting instructions. 
Accordingly, DOE proposed in the March 2022 CAC TP NOPR to revise this 
paragraph to reflect the intent of the December 2021 Correcting 
Amendment and, by extension, the January 2017 CAC TP Final Rule. 87 FR 
16830, 16845. DOE did not receive any comments and is therefore 
finalizing as proposed.
b. Revisions Specific to Appendix M1
    AHRI's comment identified one area of appendix M1 where they 
requested a change. (``AHRI Exhibit 2,'' EERE-2017-BT-STD-0062-0117 at 
p. 23) This requested change is detailed in Table III-5.

                               Table III-5--AHRI-Identified Errors to Appendix M1
----------------------------------------------------------------------------------------------------------------
                                                                                    Proposed change in the March
      Section        Original appendix M1 language       AHRI comment summary            2022  CAC TP NOPR
----------------------------------------------------------------------------------------------------------------
4.2...............  Qh(47 [deg]F): the heating      For variable speed heat        Revise the language to be
                     capacity at 47 [deg]F           pumps, the language should     clearer about what capacity
                     determined from the H2 H12or    be clarified to H\k=2\calc.    to use for different types
                     H1N test, Btu/h.                                               of heating-only heat pumps.
----------------------------------------------------------------------------------------------------------------

    The following sections discuss amendments to the language of 
appendix M1 that DOE believes will improve clarity regarding how tests 
and calculations are to be conducted to determine capacity levels and 
efficiency metrics to address the topic identified in AHRI's comment, 
additional topics in comments from interested parties, and other areas 
for improvement identified by DOE.
i. Detailed Descriptions of Capacity for Different Subcategories
    AHRI commented that in Section 4.2 of appendix M1, which describes 
the calculation for HSPF2 for different subcategories of heat pumps, 
there is a lack of clarity in the term for heating capacity measured at 
47 [deg]F, ``Qh(47 [deg]F),'' in Equation 2-2, the building 
load, ``BL(Tj),'' equation. (``AHRI Exhibit 2,'' EERE-2017-
BT-STD-0062-0117 at p. 23) Currently, the description of 
Qh(47 [deg]F) says that it is ``determined from the H, 
H12 or H1N test.'' Additionally, the first ``H'' 
is missing an additional character to specify the appropriate test 
point. DOE agrees with

[[Page 64575]]

AHRI's assessment of this description, and DOE proposed in the March 
2022 CAC TP NOPR to revise this description to include specific 
instructions for which test point is appropriate for different heat 
pump subcategories. DOE proposed to specify that the H1 test is for a 
heat pump with a single-speed compressor, the H12 test is 
for a heat pump with a two-speed compressor, and the H1N 
test is for a heat pump with a variable-speed compressor. 87 FR 16830, 
16846.
    DOE did not receive any comments in response to its proposed 
clarifications and is thus finalizing as proposed in this rule. DOE 
notes that AHRI Exhibit 2 used a ``H\k=2\calc'' term that 
does not exist in the referenced section of appendix M1. While DOE is 
revising this section to add clarity in light of AHRI's general 
comment, DOE will not be proposing to make the exact edit proposed by 
AHRI.
    ii. Heating Building Load Line for Regions Other Than IV
    Trane commented that the denominator in equation 4.2-2, the 
building heating load, ``BL(Tj),'' equation, the expression 
``Tzl-5 [deg]F'' should be replaced with ``Tzl-
TOD''. (Trane, No. 10 at p. 2) Trane asserted that they made 
this recommendation based on previous DOE rulemakings, including the 
August 2016 SNOPR for the 2017 appendix M1 rule (81 FR 58164 and 82 FR 
1426, respectively). They stated that when the building load is 
calculated for regions other than Region IV, then using 5 [deg]F 
instead of the specific region's TOD would result in 
incorrect calculation of HSPF2. Id.
    In the January 2017 CAC TP Final Rule, DOE stated that the 
appearance of TOD instead of 5 [deg]F in the denominator of 
equation 4.2-2 was a mistake, that first appeared in the November 2015 
SNOPR.\44\ 82 FR 1426, 1454. Therefore, DOE will not be making the 
change to equation 4.2-2 as suggested by Trane, and the denominator 
shall remain as ``Tzl-5 [deg]F''.
---------------------------------------------------------------------------

    \44\ Bruce Harley Energy Consulting (BHEC) provided some field 
monitoring data and analysis of heating loads conducted at the 
request of PG&E, for seven homes covering regions I/II, IV and V. 
The initial comparison of regional heating load lines with the load 
lines determined for the seven monitored locations led to the 
conclusion that equation 4.2.2 in the August 2016 SNOPR incorrectly 
included the term TOD. (BHEC, No. 28 at pp. 3-6)
---------------------------------------------------------------------------

iv. Low-Static Ducted Blower-Coil Test Procedures
    In response to the March 2022 CAC TP NOPR, AHRI and Samsung 
commented that currently, appendix M1 does not allow testing of Low 
Static Single Zone units, and requested that the definition of a low-
static blower-coil system be expanded to include some products that 
cannot accommodate the 0.5 inches w.c. necessary for testing. (AHRI, 
No. 25 at p. 7, Samsung, No. 22 at pp. 2-3) They suggested the 
following revised version of the current definition in section 1.2 of 
10 CFR part 430, appendix M1 (commenters' additions in italics):
    Low static blower-coil system means, (a) A ducted multi split or 
multi head mini split system for which the indoor unit produce greater 
than 0.01 inches w.c. and a maximum of 0.35 inches w.c. external static 
pressure when operated at the cooling full load air volume rate not 
exceeding 400 cfm per rated ton of cooling, or (b) A ducted single zone 
mini split for which the indoor unit produces a maximum of 0.25 inches 
w.c. external static pressure not exceeding 350 cfm/ton when operated 
at the highest possible air flow rate and has a rated heating or 
cooling capacity less than 24,500 Btu/h. Id.
    Samsung specifically pointed out that many of their Low Static 
Ducted Variable-Speed Mini-Split Heat Pumps (``Low Static VSMSHP'') 
were previously covered by appendix M (Table 4 of Section 3.1.4.1), but 
cannot be tested according to appendix M1, because these products have 
a maximum operating ESP of 0.24 inches w.c. and cannot operate at the 
0.5 inches w.c. set as the minimum ESP in appendix M1. (Samsung, No.22 
at pp.2-3) They further asserted that their Low Static VSMSHPs \45\ 
were designed to be installed in tight locations, that they can be 
installed with or without ducts, and that there are other manufacturers 
that Samsung is aware of that currently manufacture and sell similar 
products. (Samsung, No.22 at p.3)
---------------------------------------------------------------------------

    \45\ Samsung provided information about their Low Static VSMSHP, 
which is available online at: https://www.samsunghvac.com/light-commercial/slim-duct.
---------------------------------------------------------------------------

    DOE has received no petitions for waiver of the CAC test procedure 
from any manufacturers requesting relief from the ESP conditions set in 
appendix M1. Additionally, in the November 2015 SNOPR, DOE did propose 
to establish a ``short-ducted'' product class with lower ESP testing 
requirements (80 FR 74020, 69355) but stakeholders ultimately rejected 
this proposal, as reflected by the 2016 CAC Term Sheet recommending ESP 
levels for various types of CAC systems. Notably, ``short-duct'' 
configurations were not included in that list, so short-duct systems 
would be considered ``conventional'' single-split ducted systems. Also, 
recommendation #2 of the 2016 CAC Term Sheet states that the minimum 
required ESP for CAC/HP blower coil systems other than mobile home 
systems, ceiling-mount and wall-mount systems, low and mid-static 
multi-split systems, space-constrained systems, and small-duct, high-
velocity systems should be 0.50 inches w.c. for all capacities. (See 
2016 CAC Term Sheet: Docket No. EERE-2014-BT-STD-0048, No. 76) During 
the August 2016 SNOPR public meeting and in written comments, many 
stakeholders expressed support for the new minimum external static 
requirements that DOE proposed. JCI, Goodman, Unico, AHRI, NEEA, 
Carrier/UTC, Lennox, Ingersoll Rand, and Nortek expressed support for 
DOE's proposal to require conventional systems to be tested at a 
minimum external static pressure of 0.5 inches w.c. consistent with 
Recommendation #2 of the 2016 CAC Term Sheet. (JCI, No. 24 at p. 15; 
Goodman, No. 39 at p. 13; Unico, No. 30 at p. 6; AHRI, No. 27 at p. 16; 
NEEA, No. 35 at p. 3; Carrier/UTC, No. 36 at p. 9; Lennox, No. 25 at p. 
10; Ingersoll Rand, No. 38 at p. 5; Nortek, No. 22 at p. 11)
    Based on the evidence presented in the previous paragraph, DOE 
believes that revising the definition of low-static blower coil 
systems, as suggested by AHRI and Samsung, would conflict with the 
intent of stakeholders' comments when establishing appendix M1, and 
could potentially create an unfair competitive advantage for such 
systems by allowing more lenient testing conditions (and thus 
comparatively higher ratings) as compared to conventional centrally-
ducted systems tested at minimum ESPs exceeding 0.50 inches w.c. 
Therefore, DOE is not revising the definition for low-static blower 
coil systems in this final rule, nor is it including any new test 
provisions to accommodate these system types. DOE notes that there is 
no restriction in the definition for non-ducted indoor units that would 
preclude these systems from being tested and certified as non-ducted 
systems, comparable to 1-to-1 mini-splits. See section 1.2 of appendix 
M1. DOE also notes that its regulations at 10 CFR 430.27 provide that 
any interested person may seek a waiver from the test procedure 
requirements if certain conditions are met. A waiver allows 
manufacturers to use an alternate test procedure upon the grounds that 
the basic model contains one or more design characteristics which 
either prevent testing of the basic model according to the prescribed 
test procedures or cause the prescribed test

[[Page 64576]]

procedures to evaluate the basic model in a manner so unrepresentative 
of its true energy and/or water consumption characteristics as to 
provide materially inaccurate comparative data. 10 CFR 430.27(a)(1).
c. Revisions to Both Appendices M and M1
    AHRI Exhibit 2 claimed that there are two sections in both 
appendices M and M1 that contain similar errors. 87 FR 16830, 16846-
16847. These errors are detailed below in Table III-6. DOE is 
finalizing these revisions as proposed by AHRI and indicated in the 
table.
[GRAPHIC] [TIFF OMITTED] TR25OC22.012

    The following sections discuss changes to the language of both 
appendices M and M1 that DOE believes will improve clarity regarding 
how tests and calculations are to be conducted to determine capacity 
levels and efficiency metrics.
i. Revising Part Load Factor Equation for Heat Pumps in Section 4.2.3.3
    AHRI's comment claims that the part load factor (PLF) equation in 
section 4.2.3.3 of both appendices M and M1 contain two errors. (``AHRI 
Exhibit 2,'' EERE-2017-BT-STD-0062-0117 at p. 23) The first error is 
that the equation is missing a closing square bracket, and the second 
is that the heating mode low-capacity load factor, 
``X\k=1\(Tj),'' is incorrectly referenced instead of the 
high-capacity load factor, ``X\k=2\(Tj).'' Id. DOE notes 
that this equation is actually correct in appendix M1. The high-
capacity load factor is appropriate in this equation because section 
4.2.3.3 applies to heat pumps that only operate at high (k=2) 
compressor capacity. Therefore, the high-capacity load factor should be 
used in this case for the part load factor. In the March 2022 CAC TP 
NOPR, DOE proposed to revise this formula in appendix M to include the 
closing square bracket and to use the high-capacity load factor. 87 FR 
16830, 16846. DOE did not receive any comments in response to its 
proposal and is therefore finalizing as proposed in this rule.
    ii. Revising the Ratio of Electrical Energy Used for Resistive 
Space Heating Equation in Section 4.2.3.4
    AHRI has identified an error in the equation for electrical energy 
consumed by the heat pump for electric resistance auxiliary heating for 
bin temperature, Tj divided by the total number of hours in 
the heating season, ``RH(Tj)/N,'' used in section 4.2.3.4 of 
both appendices M and M1. AHRI indicated that the equation used in 
section 4.2.3.4 includes a multiplication operator where it should have 
subtraction. 87 FR 16830, 16846-16847. The subtraction operator is 
consistent with all other instances of RH(Tj)/N in both 
appendices M and M1. DOE agrees that the equation for 
RH(Tj)/N in section 4.2.3.4 of both appendices M and M1 is 
incorrect, and therefore DOE is revising this equation to include the 
subtraction operator rather than a multiplication operator.

E. Other Revisions Regarding Representations

    Manufacturers, including importers, must use product-specific 
certification templates to certify compliance to DOE. For CAC/HPs, the 
certification template reflects the general certification requirements 
specified at 10 CFR 429.12 and the product-specific requirements 
specified at 10 CFR 429.16. As discussed in the previous paragraphs, 
DOE is not making any amendments related to certification requirements 
in this rulemaking and any such changes may be addressed in a future 
rulemaking.
1. Required Represented Values for Models Certified Compliant With 
Regional Standards
    DOE's standards for CAC at 10 CFR 430.32(c) include both amended 
national standards with which compliance is required for models 
manufactured on or after January 1, 2023, and amended regional 
standards with which compliance is required for units installed on or 
after January 1, 2023. See 10 CFR 430.32(c)(5) and (6). In addition, as 
discussed in section III.B.3, DOE's regulations at 10 CFR 429.16 
describe certification requirements for central air conditioners

[[Page 64577]]

and central air conditioning heat pumps, and paragraph (a)(1) of the 
section requires single-split CACs with single-stage or two-stage 
compressors, at a minimum, to rate each outdoor model as part of a 
coil-only combination representative of the least efficient combination 
distributed in commerce with that particular outdoor unit.
    On December 16, 2021, DOE issued final guidance regarding whether a 
model of outdoor unit for a single-split-system AC with single-stage or 
two-stage compressor whose coil-only rating under M1 does not meet 
regional standards, but where certain blower-coil combinations that 
include the outdoor model do meet regional standards, can be installed 
in the SE or SW region (referred to in this final rule as the ``CAC 
Regional Guidance'').\46\ DOE's guidance states that ``In order to be 
installed in the SE or SW region, the outdoor unit must have at least 
one coil-only combination that is compliant with the regional standard 
applicable at the time of installation.''
---------------------------------------------------------------------------

    \46\ The CAC Regional Guidance is available online at https://www.energy.gov/sites/default/files/2021-12/cac-regional-guidance.pdf.
---------------------------------------------------------------------------

    As background, DOE finalized provisions related to this issue in 
the June 2016 CAC TP Final Rule (81 FR 36992, 37001) with subsequent 
minor revisions via the January 2017 CAC TP Final Rule (82 FR 1426); a 
July 2016 final rule regarding enforcement (81 FR 45387, July 14, 2016) 
(``July 2016 Enforcement Final Rule''); and the January 2017 CAC ECS 
Direct Final Rule (82 FR 1786, January 6, 2017). These provisions were 
based on consensus recommendations by two ASRAC Working Groups--a 
Regional Standards Enforcement Working Group (``Enforcement WG'') that 
concluded on October 24, 2014 (see final report: Docket No. EERE-2011-
BT-CE-0077, No. 70), and a Central Air Conditioner and Heat Pump Energy 
Conservation Standards Working Group (``ECS WG'') that concluded on 
January 19, 2016 (see 2016 CAC Term Sheet: Docket No. EERE-2014-BT-STD-
0048, No. 76).
    The July 2016 Enforcement Final Rule adopted several provisions of 
relevance here, with a focus on enforcement of the existing energy 
conservation standards:
     10 CFR 429.102(c)(4) contains provisions regarding what a 
``product installed in violation'' includes, specifying, among other 
things: (1) A complete central air conditioning system that is not 
certified as a complete system that meets the applicable standard; (2) 
combinations that were previously validly certified may be installed 
after the manufacturer has discontinued the combination, provided the 
combination meets the currently applicable standard; and (3) an outdoor 
unit that is part of a certified combination rated less than the 
standard applicable in the region in which it is installed. 81 FR 
45387, 45393-45394.
     10 CFR 429.158(a) specifies that if DOE determines a model 
of outdoor unit fails to meet the applicable regional standard(s) when 
tested in a combination certified by the same manufacturer, then the 
outdoor unit basic model will be deemed noncompliant with the regional 
standard(s). 81 FR 45387, 45397.
     10 CFR 430.32(c)(3) and (4) provides that any outdoor unit 
model that has a certified combination with a rating below 14 SEER 
cannot be installed in either the southern or southwest region. 81 FR 
45387, 45391.
    The June 2016 CAC TP Final Rule adopted several certification 
provisions of relevance here, with a focus on the amended energy 
conservation standards recommended by the ECS WG. In particular, the 
June 2016 CAC TP Final Rule noted that the ECS WG recommended energy 
conservation standards for central air conditioners based on coil-only 
ratings. 81 FR 36992, 37002 (June 8, 2016). The recommended standard 
levels for split system air conditioners may very well have been higher 
if they had been based on blower-coil ratings. For example, the 
recommended standard levels for split system heat pumps, which are 
based on blower-coil ratings, are approximately one point higher than 
those for split system air conditioners.
    In addition, the ECS WG recommended that DOE implement the 
requirement that every single-split air conditioner combination 
distributed in commerce must be rated, and that every single-stage and 
two-stage condensing (outdoor) unit distributed in commerce (other than 
a condensing unit for a 1-to-1 mini split) must have at least 1 coil-
only rating that is representative of the least efficient coil 
distributed in commerce with a particular condensing unit. Every 
condensing unit distributed in commerce must have at least 1 tested 
combination, and for single-stage and two-stage condensing units (other 
than condensing units for a 1-to-1 mini split) this must be a coil-only 
combination. (Docket No. EERE-2014-BT-STD-0048, No. 76, Recommendation 
#7) In the June 2016 CAC TP Final Rule, DOE adopted these 
recommendations along with regional limitations for represented values 
of individual combinations:
     10 CFR 429.16(a)(1) contains provisions for required 
represented values, stating that for single-split system AC with 
single-stage or two-stage compressor, every individual combination 
distributed in commerce must be rated as a coil-only combination. For 
each model of outdoor unit, this must include at least one coil-only 
value that is representative of the least efficient combination 
distributed in commerce with that particular model of outdoor unit. 
Additional blower-coil representations are allowed for any applicable 
individual combinations, if distributed in commerce. 81 FR 36992, 
37002.
     10 CFR 429.16(b)(2)(i) specifies that for each basic model 
of single-split system AC with single-stage or two-stage compressor, 
the model of outdoor unit must be tested with a model of coil-only 
indoor unit. 81 FR 36992, 37002.
     10 CFR 429.16(a)(4)(i) [as modified in the January 2017 
CAC TP Final Rule] states that a basic model may only be certified as 
compliant with a regional standard if all individual combinations 
within that basic model meet the regional standard for which it is 
certified, and that a model of outdoor unit that is certified below a 
regional standard can only be rated and certified as compliant with a 
regional standard if the model of outdoor unit has a unique model 
number and has been certified as a different basic model for 
distribution in each region. 81 FR 36992, 37012 [as 10 CFR 
429.16(a)(3)(i)]; 82 FR 1426.
    DOE notes that the July 2016 Enforcement Final Rule stated that the 
adopted provisions in 10 CFR 430.32(c)(3) and (4) were meant to be 
complementary to the regional limitations adopted in the June 2016 CAC 
TP Final Rule at 10 CFR 429.16(a)(3)(i) [now 10 CFR 429.16(a)(4)(i)]. 
81 FR 45387, 45391. In the January 2017 CAC ECS Direct Final Rule, DOE 
adopted additional language in 10 CFR 430.32 relevant to the amended 
standards:
     10 CFR 430.32(c)(6)(ii) provides that any outdoor unit 
model that has a certified combination with a rating below the 
applicable standard level(s) for a region cannot be installed in that 
region. The least-efficient combination of each basic model must comply 
with this standard. 82 FR 1786, 1857.
    Finally, DOE notes that the general enforcement provisions in 
subpart C to part 429 also apply to CAC standards (both national and 
regional), including:
     10 CFR 429.102(a)(1), specifying that the failure of a 
manufacturer to properly certify covered products in accordance with 10 
CFR 429.12 and 429.14 through 429.62 is a prohibited act subject to 
enforcement action.

[[Page 64578]]

    Taken together, the regional standards, certification, and 
enforcement provisions require that, in order to comply with a regional 
standard, the least efficient combination of each basic model must 
comply. 10 CFR 430.32(c)(6)(ii). Further, each basic model of single-
split system AC with single-stage or two-stage compressor must include 
a represented value for a coil-only combination representative of the 
least efficient combination distributed in commerce with the model of 
outdoor unit, and each model of outdoor unit must be tested with a 
model of coil-only indoor unit. (10 CFR 429.16(a)(1) and (b)(2)(i)) 
While manufacturers can create a regional-specific basic model under 10 
CFR 429.16(a)(4)(i), such a basic model must still be certified 
properly according to the other provisions in that section. As such, in 
order to comply with a regional standard, a regional-specific basic 
model of single-split system AC with single-stage or two-stage 
compressor must include at least one coil-only combination that 
complies with the regional standard. Failure to certify a regional-
specific basic model according to the provisions in 10 CFR 429.16(a)(1) 
and (b)(2)(i) is a prohibited act under 10 CFR 429.102(a)(1).
    Similarly, 10 CFR 429.102(c)(4)(i) states that combinations that 
were previously validly certified may be installed after the 
manufacturer has discontinued the combination, provided the combination 
meets the currently applicable standard. The provision at 10 CFR 
429.102(c)(4)(i) was designed to allow sell-through of inventory that 
manufacturers had discontinued for reasons other than non-compliance 
with a regional standard. 81 FR 45387, 45393. It was not intended, nor 
in the light of all other provisions can it be read, as allowing 
installation of models of outdoor unit that do not comply with the 
applicable regional standard at the time of installation (i.e., have no 
combinations of coil-only units that comply with the amended regional 
standards, which, as stated previously, were developed based on coil-
only ratings). Based on this background, the CAC regional guidance 
states in part:
    In general, a basic model may be certified as compliant with a 
regional standard (and, as of January 1, 2023, meets the applicable 
amended regional standard) only if all individual combinations within 
that basic model meet the regional standard for which it is certified. 
All individual model combinations within a basic model must include, 
for single-split-system AC with single-stage or two-stage compressor 
(including space-constrained and small-duct, high velocity (SDHV) 
systems), a coil-only combination representative of the least-efficient 
combination in which the specific outdoor unit is distributed in 
commerce. See 10 CFR 429.16(a)(1) and (a)(4)(i); 430.32(c)(6).
    A manufacturer may sell an outdoor unit of identical design in the 
SE and SW regions, if the manufacturer separates the basic model (i.e., 
outdoor unit model) into different basic models with unique model 
numbers for distribution in each region, provided that the basic models 
for the SE and SW regions: (1) do not include any individual 
combinations that are not compliant with the regional standard 
applicable at the time of installation; and (2) include at least one 
coil-only combination that is representative of the least-efficient 
combination in which the specific outdoor unit is distributed in 
commerce. Id.
    DOE notes that the install-through provisions in 10 CFR 
429.102(c)(4)(i) allows existing stock of discontinued basic model 
combinations to be installed in the SE or SW regions as long as they 
were previously validly certified as compliant to the regional 
standards applicable at the time of installation. DOE further notes 
that the term ``previously validly certified'' means that all 
combinations within the basic model must show compliance with the 
regional standard applicable at the time of installation, including, 
for single-split-system AC with single-stage or two-stage compressor 
(including space-constrained and SDHV systems), a coil-only combination 
representative of the least-efficient combination in which the specific 
outdoor unit is distributed in commerce, in order for the install-
through provisions to apply.
    In the March 2022 CAC TP NOPR, DOE proposed to add direction to the 
regulatory text in 10 CFR 429.16(a)(1) and (a)(4)(i), 429.102(c)(4)(i) 
and (iii), and 430.32(c)(6)(ii) to more explicitly cross-reference the 
existing regulatory text to clarify the interplay of the existing 
requirements and reinforce the guidance. 87 FR 16830, 16848.
    In addition, DOE notes that the table in 10 CFR 429.16(a)(1) states 
that the required coil-only value must be ``representative of the least 
efficient combination distributed in commerce with that particular 
model of outdoor unit'' (emphasis added). Sections 429.140 through 
429.158 provide enforcement procedures specific to regional standards, 
10 CFR 429.142 includes records retention of information regarding 
sales of outdoor units, indoor units, and single-package units, and 10 
CFR 429.144 specifies requirements for records requests. When 
determining if a model of indoor unit is distributed in commerce with a 
particular model of outdoor unit, DOE may review catalogs, product 
literature, installation instructions, and advertisements, and may also 
request sales records.
    Finally, 10 CFR 429.158 discusses products determined noncompliant 
with regional standards. Paragraphs (a) and (b) cross-reference 10 CFR 
429.102(c), stating that the certifying manufacturer is liable for 
distribution of noncompliant units in commerce. DOE notes that 10 CFR 
429.102(c) refers to distributors, contractors, and dealers, while 10 
CFR 429.102(a)(10) states that it is prohibited ``for any manufacturer 
or private labeler to knowingly sell a product to a distributor, 
contractor, or dealer with knowledge that the entity routinely violates 
any regional standard applicable to the product.'' Therefore, DOE 
proposed in the March 2022 CAC TP NOPR that 10 CFR 429.158(a) and (b) 
cross-reference 10 CFR 429.102(a)(10) rather than 10 CFR 
429.102(c).\47\ 87 FR 16830, 16848.
---------------------------------------------------------------------------

    \47\ In the March 2022 CAC TP NOPR, DOE had mistakenly modified 
10 CFR 429.102(c) to 10 CFR 429.102(b) in the regulatory text. 
Daikin has pointed this out (Daikin, No. 24 at p. 2), and the 
corrections have been made in the regulatory text for the final 
rule.
---------------------------------------------------------------------------

    In response, the Joint Advocates and Lennox declared that they 
supported DOE's proposed regulatory text in 10 CFR part 429 that 
clarified the requirements regarding required represented values for 
models certified compliant with regional standards. (Joint Advocates, 
No. 18 at p. 3, Lennox, No. 19 at p. 5) DOE is therefore finalizing its 
proposals from the March 2022 CAC TP NOPR to amend Sec. Sec.  429.16, 
429.102, 429.158, and 430.32 to clarify the interaction of the existing 
requirements and reinforce the guidance.
    Additionally, Rheem commented that DOE should provide additional 
clarity on the efficiency cross references between appendices M and M1 
for products installed on or after January 1, 2023. (Rheem, No. 21 at 
p. 4) Because Rheem did not identify any specific issues regarding the 
clarity of DOE's proposed provisions, DOE cannot further clarify them 
at this time.

F. Test Procedure Costs and Impact

    As discussed, DOE's existing test procedures for CAC/HPs appear at 
appendices M and M1 (both titled ``Uniform Test Method for Measuring 
the Energy Consumption of Central Air Conditioners and Heat Pumps''). 
In this final rule, DOE is amending the existing test procedure for 
CACs and HPs to

[[Page 64579]]

provide additional detail and instruction to ensure the 
representativeness of the test procedure and to reduce potential 
burden. DOE is making amendments in appendix M that do not impact 
testing procedures and solely provide additional clarity. DOE is also 
making limited amendments to appendix M1, which is the required test 
procedure beginning January 1, 2023. For each amendment described in 
this final rule, DOE considered the potential for changes to test 
procedure costs.
    Regarding the test procedure for variable speed coil-only central 
air conditioners and heat pumps (described in III.C.2), DOE's 
amendments provide new instructions for testing VSCO systems which are 
not currently prescribed in the DOE test procedure, despite the fact 
that these products are currently subject to energy conservation 
standards. Because the current test provisions are insufficient for 
testing VSCO, the relative cost of the amended provisions cannot be 
compared. Regarding the amendments to introduce a low-stage default 
coil-only fan power coefficient (described in III.C.1) and to revise 
the equations for full-capacity operation of variable-speed heat pumps 
at and above 45 [deg]F (described in III.D.5), DOE finds that these 
amendments would only impact calculation methods and would have no 
impact on test costs.
    There are several other test procedure amendments which DOE 
similarly does not believe will cause manufacturers to incur any 
additional test procedure costs. Specifically, the amendments described 
in section III.D.1 revise text regarding variation of fan speed with 
ambient temperature; the amendments described in section III.D.4 
explicitly indicate that the airflow measurement apparatus fan should 
be adjusted to maintain constant airflow for certain models, and the 
amendments described in section III.D.3 clarify that the instructions 
on a label affixed to the unit take precedence over the instructions 
shipped with the unit. DOE finds that these revisions each provide 
additional instruction to improve consistency of testing but do not 
increase either the number of tests or the duration of tests. The 
amendment to the wet bulb temperature maximum for the 5 [deg]F ambient 
temperature condition, discussed in section III.D.2, adjusts the 
required test condition from 3 [deg]F to 4 [deg]F. DOE proposed this 
change in part based on feedback from manufacturers that the proposed 
change to 4 [deg]F wet bulb temperature maximum would be easier to 
achieve than 3 [deg]F and would require less time spent trying to 
achieve conditions. As such, DOE does not anticipate that this 
provision would increase the burden of conducting testing under 
appendix M1.
    Finally, the amendments in 10 CFR part 429 neither modify the test 
procedure nor increase the number of units that would be required to be 
tested. Thus, DOE does not anticipate these additional procedures will 
cause any increased test procedure costs.
    DOE has, therefore, determined that the test procedures as amended 
by this final rule would improve the representativeness, accuracy, and 
reproducibility of the test results, and would not be unduly burdensome 
for manufacturers to conduct or result in increased testing cost as 
compared to the current test procedure.

G. Compliance Date and Waivers

    The effective date for the adopted test procedure amendment will be 
30 days after publication of this final rule in the Federal Register. 
EPCA prescribes that, beginning 180 days after publication of the final 
rule in the Federal Register, 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. (42 
U.S.C. 6293(c)(2)) EPCA provides an allowance for individual 
manufacturers to petition DOE for an extension of the 180-day period if 
the manufacturer may experience undue hardship in meeting the deadline. 
(42 U.S.C. 6293(c)(3)) To receive such an extension, petitions must be 
filed with DOE no later than 60 days before the end of the 180-day 
period and must detail how the manufacturer will experience undue 
hardship. Id. 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.
    Upon the compliance date of test procedure provisions in this final 
rule any waivers that had been previously issued and are in effect that 
pertain to issues addressed by such provisions are terminated. 10 CFR 
430.27(h)(3). Recipients of any such waivers are required to test the 
products subject to the waiver according to the amended test procedure 
as of the compliance date of the amended test procedure. The amendments 
adopted in this document pertain to issues addressed by waivers granted 
to GD Midea Heating and Ventilating Equipment Co. (83 FR 56065, Case 
No. 2017-013) and TCL AC (84 FR 11941, Case No. 2018-009); and interim 
waivers granted to National Comfort Products (83 FR 24754, Case No. 
2017-008), Aerosys (83 FR 24762, Case No. 2017-008), LG Electronics (85 
FR 40272, Case No. 2019-008), and Goodman (86 FR 40534, Case No. 2021-
001). To the extent such waivers and interim waivers permit the 
petitioner to test according to an alternate test procedure to appendix 
M, such waivers and interim waivers will terminate on the date testing 
is required according to appendix M1 (i.e., January 1, 2023), 
independent of this rulemaking. To the extent such waivers and interim 
waivers permit the petitioner to test according to an alternate test 
procedure to appendix M1 at such time as testing is required according 
to appendix M1, such waivers and interim waivers will terminate on 
January 1, 2023. DOE notes that the waiver issued to Johnson Controls 
(83 FR 12735, Case No. CAC-051; 84 FR 52489, Case No. CAC-050) will 
terminate on January 1, 2023, the date beginning which testing 
according to appendix M1 is required, independent of this final rule.

H. Requests for Standards Relief

    DOE understands that changes to testing requirements may create 
additional burdens for ensuring compliance with the amended energy 
conservations that take effect on January 1, 2023, and those effects 
may not be realized equally across different types and sizes of 
manufacturers. In response to the March 2022 CAC TP NOPR, DOE received 
a comment from at interested party (LBA, No. 3) requesting relief from 
standards, which is discussed.
    As previously introduced, LBA also commented on the March 2022 CAC 
TP NOPR requesting relief from energy conservations standards. 
Specifically, LBA requested DOE to delay the installation deadline for 
products that will be compliant with the new Regional Standards, citing 
the issues in unprecedented delays of products due to the current state 
of the global supply chain. (LBA, No.3 at p.1) LBA requested DOE to 
delay the installation of new CAC/HPs compliant with appendix M1 in the 
Southeast and Southwest Regions to July 1, 2023. Id. LBA stated that 
for constructions of new homes, the air handler unit, furnace and fans 
(i.e., the indoor components) are installed during the ``rough-in'' 
phase, while the outdoor condensing unit is installed several months 
later during ``closing''. Id. Hence, LBA believes that a delay in the 
deadlines of enforcement of Regional Standards would allow pairing of 
equipment compliant with the SEER1 rating (appendix M) with that 
complaint with SEER2 (appendix M1). Id.

[[Page 64580]]

    In response to the LBA request for relief, while DOE recognizes 
that manufacturers across various industries are facing unique and 
unforeseeable circumstances in light of the global effects of the 
pandemic, and that the scope of those impacts will vary by company, by 
product, and possibly even by model, DOE is not at this time extending 
this type of relief from compliance with the 2023 energy conservation 
standards. In consideration of these requests, DOE takes into account 
the full range of these circumstances and their impacts, including any 
factors that may be unique to particular products or equipment, 
including the lead time in advance of the relevant compliance date. In 
this regard, DOE notes that the regional standards applicable to 
central air conditioners installed on or after January 1, 2023, were 
adopted in a direct final rule more than five years ago, in January 
2017. Moreover, the rule was a product of negotiated rulemaking that 
included various manufacturers and trade representatives.
    Although no manufacturers specifically requested relief from 
standards, DOE notes that standards compliance is a factor in specific 
issues raised by certain commenters, specifically the case of NCP's 
space-constrained products. In its waiver request, NCP requested that 
if DOE does not incorporate provisions from the previously granted 
interim test procedure waiver into the amended Federal test procedure 
in appendix M1, then DOE must allow for NCP to continue testing and 
certifying its space-constrained CACs in a manner consistent with the 
granted test procedure waivers until 2025, noting the time needed to 
modify its condensing units and certify them as compliant with the 
amended standards, and asserted that because their space-constrained 
condensing units represent less than 0.1 percent of the overall CAC 
market, the requested delay in test procedure effective date would not 
have a significant impact on overall energy efficiency.\48\ (NCP, No 16 
at pp. 9-10) While the specific request in NCP's comments pertain to 
the testing and certification requirements, an extension of these 
provisions would effectively provide NCP with a less burdensome near-
term pathway to compliance with the 2023 standards relative to other 
manufacturers who are subject to the existing provisions. For reasons 
stated previously in this rule, DOE takes the view that, based on the 
considerations given in prior energy conservation standards and test 
procedure rulemakings, NCP and other space-constrained product 
manufacturers have had sufficient time to adjust their product designs 
to ensure compliance with the energy conservation standards.
---------------------------------------------------------------------------

    \48\ DOE is interpreting NCP's statement to mean ``overall 
energy use'', which would be the relevant metric impacted by changes 
in composition of the CAC market.
---------------------------------------------------------------------------

    However, in acknowledgement of the potential inequities in 
compliance burdens as described by NCP and LBA, DOE notes that 
additional compliance flexibilities for small business manufacturers 
may be available through other means. For example, EPCA provides that a 
manufacturer whose annual gross revenue from all of its operations does 
not exceed $8 million may apply for an exemption from all or part of an 
energy conservation standard for a period not longer than 24 months 
after the effective date of the final rule establishing the standard. 
Additionally, section 504 of the Department of Energy Organization Act 
(42 U.S.C. 7194, as codified), 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 430, subpart E, and 10 CFR part 1003 for additional 
details.
    With respect to representations, DOE notes that under 42 U.S.C. 
6293(c)(2), effective 180 days after an amended test procedure is 
prescribed or established, no manufacturer, distributor, retailer, or 
private labeler of a covered product may make any representation with 
respect to energy use or efficiency unless such product has been tested 
in accordance with such amended test procedures and such representation 
fairly discloses the results of such testing. Additionally, under 42 
U.S.C. 6293(c)(3), on the petition of any manufacturer, distributor, 
retailer, or private labeler, filed not later than the 60th day before 
the expiration of the period involved, the aforementioned 180-day 
period may be extended by the Secretary with respect to the petitioner 
(but in no event for more than an additional 180 days) if the Secretary 
determines that the requirements of paragraph (c)(2) would impose undue 
hardship on such petitioner.

IV. Procedural Issues and Regulatory Review

A. Review Under Executive Orders 12866 and 13563

    Executive Order (``E.O.'') 12866, ``Regulatory Planning and 
Review,'' as supplemented and reaffirmed by E.O. 13563, ``Improving 
Regulation and Regulatory Review,'' 76 FR 3821 (Jan. 21, 2011), 
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. 
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 a final regulatory flexibility analysis (FRFA) for any 
final rule where the agency was first required by law to publish a 
proposed rule for public comment, unless the agency certifies

[[Page 64581]]

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 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 is establishing a limited number of amendments to the test 
procedure for central air conditioners and heat pumps (``CAC/HPs'') to 
address specific issues that have been raised in test procedure waivers 
regarding appendix M1 to subpart B of 10 CFR part 430. In this final 
rule, DOE is adopting the following updates to the test procedure for 
CACs/HPs:
    1. Update default fan power coefficients and default fan heat 
coefficients for coil-only CACs and HPs that can utilize part-load air 
volume rates.
    2. Define ``variable-speed communicating coil-only central air 
conditioner or heat pump'' and prescribe an appropriate test procedure.
    3. Add the control system capability to adjust air volume rate as a 
function of outdoor air temperature for blower-coil systems with 
multiple-speed or variable-speed indoor fans.
    4. Amend the wet bulb test condition for the 5 [deg]F dry bulb, 
outdoor ambient test to have a 4 [deg]F maximum wet bulb temperature.
    5. Add direction to prioritize the instructions presented in the 
label attached to the unit over the instructions included in the 
installation instructions shipped with the unit.
    6. Add specific instruction to adjust the exhaust fan speed to 
achieve a constant cooling full-load air volume rate through the 
airflow measurement apparatus.
    7. Revise the equations representing full-capacity performance of 
variable-speed heat pumps for the temperature range above 45 [deg]F to 
be more consistent with field operation.
    8. Provide additional direction regarding the regional standard 
requirements in 10 CFR part 429.
    For manufacturers of CACs/HPs, 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,\49\ ``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. 
DOE identified manufacturers using DOE's Compliance Certification 
Database (``CCD''),\50\ the AHRI database,\51\ the California Energy 
Commission's Modernized Appliance Efficiency Database System 
(``MAEDbS''),\52\ the ENERGY STAR Product Finder database,\53\ and 
prior CAC/HP rulemakings. DOE used the publicly available information 
and subscription-based market research tools (e.g., reports from Dun & 
Bradstreet) \54\ to identify 33 original equipment manufacturers 
(``OEMs'') of the covered equipment. Of the 33 OEMs, DOE identified 
eight domestic manufacturers of CACs/HPs that meet the SBA definition 
of a ``small business.''
---------------------------------------------------------------------------

    \49\ 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 on June 20, 2022).
    \50\ DOE's Compliance Certification Database is available at: 
www.regulations.doe.gov/ccms (last accessed June 20, 2022).
    \51\ The AHRI Database is available at: www.ahridirectory.org/ 
(last accessed June 20, 2022).
    \52\ California Energy Commission's MAEDbS is available at 
cacertappliances.energy.ca.gov/Pages/ApplianceSearch.aspx (last 
accessed June 20, 2022).
    \53\ The ENERGY STAR Product Finder database is available at 
energystar.gov/productfinder/ (last accessed June 20, 2022).
    \54\ app.dnbhoovers.com.
---------------------------------------------------------------------------

    As discussed in more detail in section III.F of this document, DOE 
has determined that the amendments to the test procedure would not 
require retesting or re-rating. For variable-speed coil-only units, DOE 
notes that the test procedure adopted in this final rule provides new 
instructions for testing VSCO systems that are not currently prescribed 
in the DOE test procedure, despite the fact that these products are 
currently subject to energy conservation standards. Because the current 
test provisions are insufficient for testing VSCO, the relative cost of 
the amended provisions cannot be compared. While DOE believes the 
variable-speed coil-only units will be isolated to a very small 
fraction of models distributed in commerce (i.e., less than 1 percent 
based on manufacturer representations in DOE's current Compliance 
Management Database), a manufacturer will need to ensure their 
representations are made in accordance with these amendments. DOE notes 
that none of the variable-speed coil-only basic models certified 
currently with DOE are manufactured by small manufacturers. 
Additionally, the test procedure amendments would not result in any 
change in burden associated with the DOE test procedure for CACs/HP. 
Therefore, DOE concludes that the test procedure amendments in this 
final rule would not have a ``significant economic impact on a 
substantial number of small entities,'' and that the preparation of a 
FRFA is not warranted. DOE will transmit the 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 central air conditioners and heat pumps must 
certify to DOE that their products comply with any applicable energy 
conservation standards. To certify compliance, manufacturers must first 
obtain test data for their products 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 central air conditioners and heat pumps. (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 
central air conditioners and heat pumps in this final rule. Instead, 
DOE may consider proposals to amend the certification requirements and 
reporting central air conditioners and heat pumps under a separate 
rulemaking regarding appliance and equipment certification. DOE will 
address changes to OMB Control Number 1910-1400 at that time, as 
necessary.

[[Page 64582]]

    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.

D. Review Under the National Environmental Policy Act of 1969

    In this final rule, DOE establishes test procedure amendments that 
it expects will be used to develop and implement future energy 
conservation standards for central air conditioners and heat pumps. 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, appendix A to subpart D, 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. 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 requires Executive 
agencies to review regulations in light of applicable standards in 
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 resulting 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 proposed ``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 small governments. On March 18, 1997, 
DOE published a statement of policy on its process for 
intergovernmental consultation under UMRA. 62 FR 12820; also available 
at www.energy.gov/gc/office-general-counsel. 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

[[Page 64583]]

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.

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 OMB, 
a Statement of Energy Effects for any significant energy action. A 
``significant energy action'' is defined as any action by an agency 
that promulgated 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 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 central air 
conditioners and heat pumps adopted in this final rule do not 
incorporate any new commercial standards or test procedures that are 
not already incorporated by reference \55\ at 10 CFR 430.3 and 
therefore DOE has not re-assessed such standards as part of this final 
rule.
---------------------------------------------------------------------------

    \55\ The June 2016 CAC TP Final Rule incorporated by reference 
into appendix M several commercial standards and test procedures. 81 
FR 36992, 37056-37057. In the January 2017 CAC TP Final Rule, DOE 
incorporated by reference in appendix M1 the same set of standards 
and test procedures. 82 FR 1426, 1467.
---------------------------------------------------------------------------

M. Description of Materials Incorporated by Reference.

    The following standard was previously approved for incorporation by 
reference in appendix M1 where it appears, and no change is being made:
    ANSI/ASHRAE Standard 37-2009, Methods of Testing for Rating 
Electrically Driven Unitary Air-Conditioning and Heat Pump Equipment, 
ANSI approved June 25, 2009;

N. 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 it has been determined that the rule is not a ``major rule'' 
as defined by 5 U.S.C. 804(2).

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, 
Intergovernmental relations, Reporting and recordkeeping requirements, 
Small businesses.

10 CFR Part 430

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

Signing Authority

    This document of the Department of Energy was signed on October 5, 
2022, by Francisco Alejandro Moreno, Acting 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 October 7, 2022.
Treena V. Garrett,
Federal Register Liaison Officer, U.S. Department of Energy.
    For the reasons stated in the preamble, DOE amends parts 429 and 
430 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. Section 429.16 is amended by:
0
a. Revising table 1 to paragraph (a)(1);
0
b. Revising paragraph (a)(4)(i); and
0
c. Revising the table in paragraph (b)(2)(i).
    The revisions read as follows:


Sec.  429.16  Central air conditioners and central air conditioning 
heat pumps.

    (a) * * *
    (1) * * *

[[Page 64584]]



                       Table 1 to Paragraph (a)(1)
------------------------------------------------------------------------
                                    Equipment       Required represented
          Category                 subcategory             values
------------------------------------------------------------------------
Single-Package Unit.........  Single-Package Air    Every individual
                               Conditioner (AC)      model distributed
                               (including space-     in commerce.
                               constrained).
                              Single-Package Heat
                               Pump (HP)
                               (including space-
                               constrained).
Outdoor Unit and Indoor Unit  Single-Split-System   Every individual
 (Distributed in Commerce by   AC with Single-       combination
 Outdoor Unit Manufacturer     Stage or Two-Stage    distributed in
 (OUM)).                       Compressor            commerce. Each
                               (including Space-     model of outdoor
                               Constrained and       unit must include a
                               Small-Duct, High      represented value
                               Velocity Systems      for at least one
                               (SDHV)).              coil-only
                                                     individual
                                                     combination that is
                                                     distributed in
                                                     commerce and which
                                                     is representative
                                                     of the least
                                                     efficient
                                                     combination
                                                     distributed in
                                                     commerce with that
                                                     particular model of
                                                     outdoor unit. For
                                                     that particular
                                                     model of outdoor
                                                     unit, additional
                                                     represented values
                                                     for coil-only and
                                                     blower-coil
                                                     individual
                                                     combinations are
                                                     allowed, if
                                                     distributed in
                                                     commerce.
                              Single-Split System   Every individual
                               AC with Other Than    combination
                               Single-Stage or Two-  distributed in
                               Stage Compressor      commerce, including
                               (including Space-     all coil-only and
                               Constrained and       blower-coil
                               SDHV).                combinations.
                              Single-Split-System   Every individual
                               HP (including Space-  combination
                               Constrained and       distributed in
                               SDHV).                commerce.
                              Multi-Split, Multi-   For each model of
                               Circuit, or Multi-    outdoor unit, at a
                               Head Mini-Split       minimum, a non-
                               Split System--non-    ducted ``tested
                               SDHV (including       combination.'' For
                               Space-Constrained).   any model of
                                                     outdoor unit also
                                                     sold with models of
                                                     ducted indoor
                                                     units, a ducted
                                                     ``tested
                                                     combination.'' When
                                                     determining
                                                     represented values
                                                     on or after January
                                                     1, 2023, the ducted
                                                     ``tested
                                                     combination'' must
                                                     comprise the
                                                     highest static
                                                     variety of ducted
                                                     indoor unit
                                                     distributed in
                                                     commerce (i.e.,
                                                     conventional, mid-
                                                     static, or low-
                                                     static). Additional
                                                     representations are
                                                     allowed, as
                                                     described in
                                                     paragraphs
                                                     (c)(3)(i) and (ii)
                                                     of this section,
                                                     respectively.
                              Multi-Split, Multi-   For each model of
                               Circuit, or Multi-    outdoor unit, an
                               Head Mini-Split       SDHV ``tested
                               Split System--SDHV.   combination.''
                                                     Additional
                                                     representations are
                                                     allowed, as
                                                     described in
                                                     paragraph
                                                     (c)(3)(iii) of this
                                                     section.
Indoor Unit Only Distributed  Single-Split-System   Every individual
 in Commerce by Independent    Air Conditioner       combination
 Coil Manufacturer (ICM).      (including Space-     distributed in
                               Constrained and       commerce.
                               SDHV).
                              Single-Split-System
                               Heat Pump
                               (including Space-
                               Constrained and
                               SDHV).
                              Multi-Split, Multi-   For a model of
                               Circuit, or Multi-    indoor unit within
                               Head Mini-Split       each basic model,
                               Split System--SDHV.   an SDHV ``tested
                                                     combination.''
                                                     Additional
                                                     representations are
                                                     allowed, as
                                                     described in
                                                     paragraph
                                                     (c)(3)(iii) of this
                                                     section.
------------------------------------------------------------------------
            Outdoor Unit with no Match              Every model of
                                                     outdoor unit
                                                     distributed in
                                                     commerce (tested
                                                     with a model of
                                                     coil-only indoor
                                                     unit as specified
                                                     in paragraph
                                                     (b)(2)(i) of this
                                                     section).
------------------------------------------------------------------------

* * * * *
    (4) * * *
    (i) Regional. A basic model (model of outdoor unit) may only be 
certified as compliant with a regional standard if all individual 
combinations within that basic model meet the regional standard for 
which it is certified, including the coil-only combination as specified 
in paragraph (a)(1) of this section, as applicable. A model of outdoor 
unit that is certified below a regional standard can only be rated and 
certified as compliant with a regional standard if the model of outdoor 
unit has a unique model number and has been certified as a different 
basic model for distribution in each region, where the basic model(s) 
certified as compliant with a regional standard meet the requirements 
of the first sentence. An ICM cannot certify an individual combination 
with a rating that is compliant with a regional standard if the 
individual combination includes a model of outdoor unit that the OUM 
has certified with a rating that is not compliant with a regional 
standard. Conversely, an ICM cannot certify an individual combination 
with a rating that is not compliant with a regional standard if the 
individual combination includes a model of outdoor unit that an OUM has 
certified with a rating that is compliant with a regional standard.
* * * * *
    (b) * * *
    (2) * * *
    (i) * * *

[[Page 64585]]



                                         Table 2 to Paragraph (b)(2)(i)
----------------------------------------------------------------------------------------------------------------
              Category                Equipment subcategory        Must test:                   With:
----------------------------------------------------------------------------------------------------------------
Single-Package Unit................  Single-Package AC       The individual model    N/A.
                                      (including Space-       with the lowest
                                      Constrained).           seasonal energy
                                     Single-Package HP        efficiency ratio
                                      (including Space-       (SEER) (when testing
                                      Constrained).           in accordance with
                                                              appendix M to subpart
                                                              B of 10 CFR part 430)
                                                              or SEER2 (when
                                                              testing in accordance
                                                              with appendix M1 to
                                                              subpart B of 10 CFR
                                                              part 430).
Outdoor Unit and Indoor Unit         Single-Split-System AC  The model of outdoor    A model of coil-only indoor
 (Distributed in Commerce by OUM).    with Single-Stage or    unit.                   unit.
                                      Two-Stage Compressor
                                      (including Space-
                                      Constrained and Small-
                                      Duct, High Velocity
                                      Systems (SDHV)).
                                     Single-Split-System HP  The model of outdoor    A model of indoor unit.
                                      with Single-Stage or    unit.
                                      Two-Stage Compressor
                                      (including Space-
                                      Constrained and SDHV).
                                     Single-Split System AC  The model of outdoor    A model of non-
                                      or HP with Other Than   unit.                   communicating coil-only
                                      Single-Stage or Two-                            indoor unit.
                                      Stage Compressor
                                      having a non-
                                      communicating coil-
                                      only individual
                                      combination
                                      (including Space-
                                      Constrained and SDHV).
                                     Single-Split System AC  The model of outdoor    A model of indoor unit.
                                      or HP with Other Than   unit.
                                      Single-Stage or Two-
                                      Stage Compressor
                                      without a non-
                                      communicating coil-
                                      only individual
                                      combination
                                      (including Space-
                                      Constrained and SDHV).
                                     Multi-Split, Multi-     The model of outdoor    At a minimum, a ``tested
                                      Circuit, or Multi-      unit.                   combination'' composed
                                      Head Mini-Split Split                           entirely of non-ducted
                                      System--non-SDHV                                indoor units. For any
                                      (including Space-                               models of outdoor units
                                      Constrained).                                   also sold with models of
                                                                                      ducted indoor units, test
                                                                                      a second ``tested
                                                                                      combination'' composed
                                                                                      entirely of ducted indoor
                                                                                      units (in addition to the
                                                                                      non-ducted combination).
                                                                                      If testing under appendix
                                                                                      M1 to subpart B of 10 CFR
                                                                                      part 430, the ducted
                                                                                      ``tested combination''
                                                                                      must comprise the highest
                                                                                      static variety of ducted
                                                                                      indoor unit distributed in
                                                                                      commerce (i.e.,
                                                                                      conventional, mid-static,
                                                                                      or low-static).
                                     Multi-Split, Multi-     The model of outdoor    A ``tested combination''
                                      Circuit, or Multi-      unit.                   composed entirely of SDHV
                                      Head Mini-Split Split                           indoor units.
                                      System--SDHV.
Indoor Unit Only (Distributed in     Single-Split-System     A model of indoor unit  The least efficient model
 Commerce by ICM).                    Air Conditioner                                 of outdoor unit with which
                                      (including Space-                               it will be paired where
                                      Constrained and SDHV).                          the least efficient model
                                                                                      of outdoor unit is the
                                                                                      model of outdoor unit in
                                                                                      the lowest SEER
                                                                                      combination (when testing
                                                                                      under appendix M to
                                                                                      subpart B of 10 CFR part
                                                                                      430) or SEER2 combination
                                                                                      (when testing under
                                                                                      appendix M1 to subpart B
                                                                                      of 10 CFR part 430) as
                                                                                      certified by the OUM. If
                                                                                      there are multiple models
                                                                                      of outdoor unit with the
                                                                                      same lowest SEER (when
                                                                                      testing under appendix M
                                                                                      to subpart B of 10 CFR
                                                                                      part 430) or SEER2 (when
                                                                                      testing under appendix M1
                                                                                      to subpart B of 10 CFR
                                                                                      part 430) represented
                                                                                      value, the ICM may select
                                                                                      one for testing purposes.
                                     Single-Split-System     Nothing, as long as an  ...........................
                                      Heat Pump (including    equivalent air
                                      Space-Constrained and   conditioner basic
                                      SDHV).                  model has been tested
                                                              If an equivalent air
                                                              conditioner basic
                                                              model has not been
                                                              tested, must test a
                                                              model of indoor unit.
                                     Multi-Split, Multi-     A model of indoor unit  A ``tested combination''
                                      Circuit, or Multi-                              composed entirely of SDHV
                                      Head Mini-Split Split                           indoor units, where the
                                      System--SDHV.                                   outdoor unit is the least
                                                                                      efficient model of outdoor
                                                                                      unit with which the SDHV
                                                                                      indoor unit will be
                                                                                      paired. The least
                                                                                      efficient model of outdoor
                                                                                      unit is the model of
                                                                                      outdoor unit in the lowest
                                                                                      SEER combination (when
                                                                                      testing under appendix M
                                                                                      to subpart B of 10 CFR
                                                                                      part 430) or SEER2
                                                                                      combination (when testing
                                                                                      under appendix M1 to
                                                                                      subpart B of 10 CFR part
                                                                                      430) as certified by the
                                                                                      OUM. If there are multiple
                                                                                      models of outdoor unit
                                                                                      with the same lowest SEER
                                                                                      represented value (when
                                                                                      testing under appendix M
                                                                                      to subpart B of 10 CFR
                                                                                      part 430) or SEER2
                                                                                      represented value (when
                                                                                      testing under appendix M1
                                                                                      to subpart B of 10 CFR
                                                                                      part 430), the ICM may
                                                                                      select one for testing
                                                                                      purposes.
Outdoor Unit with No Match.........  ......................  The model of outdoor    A model of coil-only indoor
                                                              unit.                   unit meeting the
                                                                                      requirements of section
                                                                                      2.2e of appendix M or M1
                                                                                      to subpart B of 10 CFR
                                                                                      part 430.
----------------------------------------------------------------------------------------------------------------


[[Page 64586]]

* * * * *

0
3. Section 429.102 is amended by revising paragraphs (c)(4)(i) and 
(iii) to read as follows:


Sec.  429.102  Prohibited acts subjecting persons to enforcement 
action.

* * * * *
    (c) * * *
    (4) * * *
    (i) A complete central air conditioning system that is not 
certified as a complete system that meets the applicable standard. 
Combinations that were previously validly certified may be installed 
after the manufacturer has discontinued the combination, provided all 
combinations within the basic model, including for single-split-system 
AC with single-stage or two-stage compressor at least one coil-only 
combination as specified in paragraph (a)(1) of this section, comply 
with the regional standard applicable at the time of installation.
* * * * *
    (iii) An outdoor unit that is part of a certified combination rated 
less than the standard applicable in the region in which it is 
installed or, where applicable, an outdoor unit with no certified coil-
only combination as specified in paragraph (a)(1) of this section that 
meets the standard applicable in the region in which it is installed.


Sec.  429.158  [Amended]

0
4. Section 429.158 is amended by removing ``Sec.  429.102(c)'' in 
paragraphs (a) and (b) and adding in its place ``Sec.  
429.102(a)(10)''.

PART 430--ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS

0
5. The authority citation for part 430 continues to read as follows:

    Authority: 42 U.S.C. 6291-6309; 28 U.S.C. 2461 note.

0
6. Section 430.2 is amended by revising the definition for ``Central 
air conditioner or central air conditioning heat pump'' to read as 
follows:


Sec.  430.2  Definitions.

* * * * *
    Central air conditioner or central air conditioning heat pump means 
a product, other than a packaged terminal air conditioner, packaged 
terminal heat pump, single-phase single-package vertical air 
conditioner with cooling capacity less than 65,000 Btu/h, single-phase 
single-package vertical heat pump with cooling capacity less than 
65,000 Btu/h, computer room air conditioner, or unitary dedicated 
outdoor air system as these equipment categories are defined at 10 CFR 
431.92, which is powered by single phase electric current, air cooled, 
rated below 65,000 Btu per hour, not contained within the same cabinet 
as a furnace, the rated capacity of which is above 225,000 Btu per 
hour, and is a heat pump or a cooling unit only. A central air 
conditioner or central air conditioning heat pump may consist of: A 
single-package unit; an outdoor unit and one or more indoor units; an 
indoor unit only; or an outdoor unit with no match. In the case of an 
indoor unit only or an outdoor unit with no match, the unit must be 
tested and rated as a system (combination of both an indoor and an 
outdoor unit). For all central air conditioner and central air 
conditioning heat pump-related definitions, see appendix M or M1 of 
subpart B of this part.
* * * * *

0
7. Section 430.32 is amended by revising paragraph (c)(6)(ii) to read 
as follows:


Sec.  430.32  Energy and water conservation standards and their 
compliance dates.

* * * * *
    (c) * * *
    (6) * * *
    (ii) Any model of outdoor unit that has a certified combination 
with a rating below the applicable standard level(s) for a region 
cannot be installed in that region. The least-efficient combination of 
each basic model, which for single-split-system air conditioner (AC) 
with single-stage or two-stage compressor (including space-constrained 
and small-duct high velocity systems (SDHV)) must be a coil-only 
combination, must comply with the applicable standard. See 10 CFR 
429.16(a)(1) and (a)(4)(i).
* * * * *

0
8. Appendix M to subpart B of part 430 is amended by:
0
a. Revising the Note;
0
b. Revising the definition of ``nominal capacity'' in section 1.2;
0
c. Revising paragraph a. in section 3.6.4;
0
d. Revising section 4.1.4.2;
0
e. Revising the introductory text to section 4.2.3;
0
f. Revising the equations following the word ``Where:'' in section 
4.2.3.3; and
0
g. Revising section 4.2.3.4.
    The revisions read as follows:

Appendix M to Subpart B of Part 430--Uniform Test Method for Measuring 
the Energy Consumption of Central Air Conditioners and Heat Pumps

    Note: Prior to January 1, 2023, if using the appendix M test 
procedure for representations, including compliance certifications, 
with respect to the energy use, power, or efficiency of central air 
conditioners and central air conditioning heat pumps, any such 
representations must be based on the results of testing pursuant to 
either this appendix or the procedures in appendix M as it appeared 
at 10 CFR part 430, subpart B, in the 10 CFR parts 200 to 499 
edition revised as of January 1, 2022. Any representations made with 
respect to the energy use or efficiency of such central air 
conditioners and central air conditioning heat pumps must be in 
accordance with whichever version is selected. Any representations, 
including compliance certifications, made with respect to the energy 
use, power, or efficiency of central air conditioners and central 
air conditioning heat pumps made on or after January 1, 2023, must 
be based on the results of testing pursuant the procedures in 
appendix M1 to this subpart.

* * * * *

1. * * *

1.2 Definitions

* * * * *
    Nominal capacity means the capacity that is claimed by the 
manufacturer on the product name plate. Nominal cooling capacity is 
approximate to the air conditioner cooling capacity tested at A or 
A2 condition. Nominal heating capacity is approximate to 
the heat pump heating capacity tested in H1N test.
* * * * *

3. * * *

3.6.4 Tests for a Heat Pump Having a Variable-Speed Compressor

    a. Conduct one maximum temperature test (H01), two 
high temperature tests (H1N and H11), one 
frost accumulation test (H2V), and one low temperature 
test (H32). Conducting one or both of the following tests 
is optional: An additional high temperature test (H12) 
and an additional frost accumulation test (H22). If 
desired, conduct the optional maximum temperature cyclic 
(H0C1) test to determine the heating mode cyclic-
degradation coefficient, CD\h\. If this optional test is 
conducted but yields a tested CD\h\ that exceeds the 
default CD\h\ or if the optional test is not conducted, 
assign CD\h\ the default value of 0.25. Test conditions 
for the eight tests are specified in Table 14 to this appendix. The 
compressor shall operate at the same heating full speed, measured by 
RPM or power input frequency (Hz), for the H12, 
H22 and H32 tests. For a cooling/heating heat 
pump, the compressor shall operate for the H1N test at a 
speed, measured by RPM or power input frequency (Hz), no lower than 
the speed used in the A2 test if the tested 
H1N heating capacity is less than the tested 
A2 cooling capacity. The compressor shall operate at the 
same heating minimum speed, measured by RPM or power input frequency 
(Hz), for the H01, H1C1, and H11 
tests. Determine the heating intermediate compressor speed cited in 
Table 14 using the heating mode full and minimum compressors speeds 
and:

[[Page 64587]]

[GRAPHIC] [TIFF OMITTED] TR25OC22.013

Where a tolerance on speed of plus 5 percent or the next higher 
inverter frequency step from the calculated value is allowed.
* * * * *

4. * * *

4.1.4.2 Unit Operates at an Intermediate Compressor Speed (k=i) In 
Order To Match the Building Cooling Load at Temperature Tj, 
Qc\k=1\(Tj) < BL(Tj) < 
Qc\k=2\(Tj)
[GRAPHIC] [TIFF OMITTED] TR25OC22.014

[GRAPHIC] [TIFF OMITTED] TR25OC22.015

Where:

Qc\k=i\(Tj) = BL(Tj), the space 
cooling capacity delivered by the unit in matching the building load 
at temperature Tj, Btu/h. The matching occurs with the 
unit operating at compressor speed k=i.
[GRAPHIC] [TIFF OMITTED] TR25OC22.016

EER\k=i\(Tj) = the steady-state energy efficiency ratio 
of the test unit when operating at a compressor speed of k=i and 
temperature Tj, Btu/h per W.

    Obtain the fractional bin hours for the cooling season, 
nj/N, from Table 19 to this appendix. For each 
temperature bin where the unit operates at an intermediate 
compressor speed, determine the energy efficiency ratio 
EER\k=i\(Tj) using, EERk=i(Tj) = A + B Tj + C * T2j.
    For each unit, determine the coefficients A, B, and C by 
conducting the following calculations once:
[GRAPHIC] [TIFF OMITTED] TR25OC22.017

Where:

T1 = the outdoor temperature at which the unit, when 
operating at minimum compressor speed, provides a space cooling 
capacity that is equal to the building load 
(Qc\k=l\(Tl) = BL(T1)), [deg]F. 
Determine T1 by equating Equations 4.1.3-1 and 4.1-2 to 
this appendix and solving for outdoor temperature.
Tv = the outdoor temperature at which the unit, when 
operating at the intermediate compressor speed used during the 
section 3.2.4 Ev test of this appendix, provides a space 
cooling capacity that is equal to the building load 
(Qc\k=v\(Tv) = BL(Tv)), [deg]F. 
Determine Tv by equating Equations 4.1.4-3 and 4.1-2 to 
this appendix and solving for outdoor temperature.
T2 = the outdoor temperature at which the unit, when 
operating at full compressor speed, provides a space cooling 
capacity that is equal to the building load 
(Qc\k=2\(T2) = BL(T2)), [deg]F. 
Determine T2 by equating Equations 4.1.3-3 and 4.1-2 to 
this appendix and solving for outdoor temperature.

[GRAPHIC] [TIFF OMITTED] TR25OC22.018


[[Page 64588]]


* * * * *

4.2.3 Additional Steps for Calculating the HSPF of a Heat Pump Having a 
Two-Capacity Compressor

    The calculation of the Equation 4.2-1 to this appendix 
quantities differ depending upon whether the heat pump would operate 
at low capacity (section 4.2.3.1 of this appendix), cycle between 
low and high capacity (section 4.2.3.2 of this appendix), or operate 
at high capacity (sections 4.2.3.3 and 4.2.3.4 of this appendix) in 
responding to the building load. For heat pumps that lock out low 
capacity operation at low outdoor temperatures, the outdoor 
temperature at which the unit locks out must be that specified by 
the manufacturer in the certification report so that the appropriate 
equations can be selected.
* * * * *

4.2.3.3 Heat Pump Only Operates at High (k=2) Compressor Capacity at 
Temperature Tj and Its Capacity Is Greater Than the Building 
Heating Load, BL(Tj) < Qh\k=2\(Tj)

* * * * *
XK=2(TJ) = BL(Tj/Qk=2h(Tj); and
PLFj = 1-ChD (k = 2) * [1-Xk=2(Tj)].
* * * * *

4.2.3.4 Heat Pump Must Operate Continuously at High (k=2) Compressor 
Capacity at Temperature Tj, BL(Tj) = 
Qh\k=2\(Tj)
[GRAPHIC] [TIFF OMITTED] TR25OC22.019

Where:
[GRAPHIC] [TIFF OMITTED] TR25OC22.020

* * * * *

0
9. Appendix M1 to subpart B of part 430 is amended by:
0
a. Adding a Note;
0
b. Adding in alphabetical order definitions for ``Variable-speed 
communicating coil-only central air conditioner or heat pump'' and 
``Variable-speed non-communicating coil-only central air conditioner or 
heat pump'' in section 1.2;
0
c. Revising paragraph (B) and the undesignated paragraph following it 
and adding a second undesignated paragraph in section 2;
0
d. Revising section 3.1.2;
0
e. Revising paragraphs a. and b. in section 3.1.4.1.1;
0
f. Revising paragraphs a. and b. and adding paragraph f. in section 
3.1.4.2:
0
g. Revising paragraph b. and adding paragraph d. in section 3.1.4.3;
0
h. Revising paragraph a. in section 3.1.4.4.3;
0
i. Adding paragraph d. in section 3.1.4.6;
0
j. Revising section 3.1.4.7;
0
k. Revising paragraph a., adding paragraph d. immediately following 
paragraph c., and revising Table 8 in section 3.2.4;
0
l. Revising paragraph d., redesignating paragraph e. as paragraph f., 
and adding a new paragraph e. in section 3.3;
0
m. Revising the introductory text, redesignating paragraphs a. and b. 
as paragraphs c. and d., respectively, adding new paragraphs a. and b., 
and revising newly redesignated paragraph c. in section 3.5.1;
0
n. Revising Table 11 in section 3.6.1;
0
o. Revising Table 12 in section 3.6.2;
0
p. Revising Table 13 in section 3.6.3;
0
q. Revising section 3.6.4 and adding sections 3.6.4.1 and 3.6.4.2;
0
r. Revising Table 15 in section 3.6.6;
0
s. Revising paragraph c., redesignating paragraphs d. and e. as 
paragraphs e. and f., respectively, and adding new paragraph d. in 
section 3.7;
0
t. Revising paragraph b. in section 3.8;
0
u. Revising paragraph b. in section 3.9.1;
0
v. Revising section 4.1.4;
0
w. Adding sections 4.1.4.2.1 and 4.1.4.2.2;
0
x. Revising the undesignated text after Table 20 and before paragraph 
a., including Equation 4.2-2, in section 4.2;
0
y. Revising the introductory text for section 4.2.3;
0
z. Revising section 4.2.3.4;
0
aa. Revising paragraphs a., b., c., and e., in section 4.2.4;
0
bb. Revising sections 4.2.4.1 and 4.2.4.2; and
0
cc. Removing the language ``and X\k=3\(Tj) = 
X\k=2\(Tj)'' and adding in its place ``and 
X\k=3\(Tj) = 1-X\k=2\(Tj)'' in section 4.2.6.5.
    The revisions and additions read as follows:

Appendix M1 to Subpart B of Part 430--Uniform Test Method for Measuring 
the Energy Consumption of Central Air Conditioners and Heat Pumps

    Note: On or after January 1, 2023, and prior to April 24, 2023, 
any representations, including compliance certifications, made with 
respect to the energy use, power, or efficiency of central air 
conditioners and central air conditioning heat pumps must be based 
on the results of testing pursuant to either this appendix or the 
procedures in appendix M1 as it appeared at 10 CFR part 430, subpart 
B, in the 10 CFR parts 200 to 499 edition revised as of January 1, 
2022.

[[Page 64589]]

Any representations made with respect to the energy use or 
efficiency of such central air conditioners and central air 
conditioning heat pumps must be in accordance with whichever version 
is selected.

    On or after April 24, 2023, any representations, including 
compliance certifications, made with respect to the energy use, 
power, or efficiency of central air conditioners and central air 
conditioning heat pumps must be based on the results of testing 
pursuant to this appendix.
* * * * *

1.2 Definitions

* * * * *
    Variable-speed communicating coil-only central air conditioner 
or heat pump means a variable-speed compressor system having a coil-
only indoor unit that is installed with a control system that:
    (a) Communicates the difference in space temperature and space 
setpoint temperature (not a setpoint value inferred from on/off 
thermostat signals) to the control that sets compressor speed;
    (b) Provides a signal to the indoor fan to set fan speed 
appropriate for compressor staging; and
    (c) Has installation instructions indicating that the control 
system having these capabilities must be installed.
* * * * *
    Variable-speed non-communicating coil-only central air 
conditioner or heat pump means a variable-speed compressor system 
having a coil-only indoor unit that is does not meet the definition 
of variable-speed communicating coil-only central air conditioner or 
heat pump.
* * * * *

2 Testing Overview and Conditions

* * * * *
    (B) For systems other than VRF, only a subset of the sections 
listed in this test procedure apply when testing and determining 
represented values for a particular unit. Table 1 to this appendix 
shows the sections of the test procedure that apply to each system. 
Table 1 is meant to assist manufacturers in finding the appropriate 
sections of the test procedure. Manufacturers are responsible for 
determining which sections apply to each unit tested based on the 
model characteristics. The appendix sections provide the specific 
requirements for testing. To use Table 1, first refer to the 
sections listed under ``all units''. Then refer to additional 
requirements based on:
    (1) System configuration(s),
    (2) The compressor staging or modulation capability, and
    (3) Any special features.
    Testing requirements for space-constrained products do not 
differ from similar products that are not space-constrained, and 
thus space-constrained products are not listed separately in Table 
1. Air conditioners and heat pumps are not listed separately in 
Table 1, but heating procedures and calculations apply only to heat 
pumps.
    The ``manufacturer's published instructions,'' as stated in 
Section 8.2 of ANSI/ASHRAE Standard 37-2009 (incorporated by 
reference, see Sec.  430.3) and ``manufacturer's installation 
instructions'' discussed in this appendix mean the manufacturer's 
installation instructions that come packaged with the unit or appear 
in the labels applied to the unit. Manufacturer's installation 
instructions do not include online manuals. Installation 
instructions that appear in the labels applied to the unit shall 
take precedence over installation instructions that come packaged 
with the unit.
* * * * *

3.1.2 Manufacturer-Provided Equipment Overrides

    Where needed, the manufacturer must provide a means for 
overriding the controls of the test unit so that the compressor(s) 
operates at the specified speed or capacity and the indoor blower 
operates at the specified speed or delivers the specified air volume 
rate. For variable-speed non-communicating coil-only air 
conditioners and heat pumps, the control system shall be provided 
with a control signal indicating operation at high or low stage, 
rather than testing with the compressor speed fixed at specific 
speeds, with the exception that compressor speed override may be 
used for heating mode test H12.
* * * * *

3.1.4.1.1 Cooling Full-Load Air Volume Rate for Ducted Units

* * * * *
    a. For all ducted blower-coil systems, except those having a 
constant-air-volume-rate indoor blower:
    Step (1) Operate the unit under conditions specified for the A 
test (for single-stage units) or A2 test (for non-single-
stage units) using the certified fan speed or controls settings, and 
adjust the exhaust fan of the airflow measuring apparatus to achieve 
the certified cooling full-load air volume rate;
    Step (2) Measure the external static pressure;
    Step (3) If this external static pressure is equal to or greater 
than the applicable minimum external static pressure cited in Table 
4 to this appendix, the pressure requirement is satisfied; proceed 
to step 7 of this section. If this external static pressure is not 
equal to or greater than the applicable minimum external static 
pressure cited in Table 4, proceed to step 4 of this section;
    Step (4) Increase the external static pressure by adjusting the 
exhaust fan of the airflow measuring apparatus until the first to 
occur of:
    (i) The applicable Table 4 to this appendix minimum is equaled 
or
    (ii) The measured air volume rate equals 90 percent or less of 
the cooling full-load air volume rate;
    Step (5) If the conditions of step 4 (i) of this section occur 
first, the pressure requirement is satisfied; proceed to step 7 of 
this section. If the conditions of step 4 (ii) of this section occur 
first, proceed to step 6 of this section;
    Step (6) Make an incremental change to the setup of the indoor 
blower (e.g., next highest fan motor pin setting, next highest fan 
motor speed) and repeat the evaluation process beginning at step 1 
of this section. If the indoor blower setup cannot be further 
changed, increase the external static pressure by adjusting the 
exhaust fan of the airflow measuring apparatus until the applicable 
Table 4 to this appendix minimum is equaled; proceed to step 7 of 
this section;
    Step (7) The airflow constraints have been satisfied. Use the 
measured air volume rate as the cooling full-load air volume rate. 
Use the final indoor fan speed or control settings of the unit under 
test for all tests that use the cooling full-load air volume rate. 
Adjust the fan of the airflow measurement apparatus if needed to 
obtain the same full-load air volume rate (in scfm) for all such 
tests, unless the system modulates indoor blower speed with outdoor 
dry bulb temperature or to adjust the sensible to total cooling 
capacity ratio--in this case, use an air volume rate that represents 
a normal installation and calculate the target external static 
pressure as described in section 3.1.4.2 of this appendix.
    b. For ducted blower-coil systems with a constant-air-volume-
rate indoor blower. For all tests that specify the cooling full-load 
air volume rate, obtain an external static pressure as close to (but 
not less than) the applicable Table 4 to this appendix value that 
does not cause either automatic shutdown of the indoor blower or a 
value of air volume rate variation QVar, defined as 
follows, that is greater than 10 percent.
[GRAPHIC] [TIFF OMITTED] TR25OC22.021

Where:

Qmax = maximum measured airflow value
Qmin = minimum measured airflow value
QVar = airflow variance, percent

    Additional test steps as described in section 3.3.f of this 
appendix are required if the measured external static pressure 
exceeds the target value by more than 0.03 inches of water.
* * * * *

3.1.4.2 Cooling Minimum Air Volume Rate

* * * * *
    a. For a ducted blower-coil system without a constant-air-volume 
indoor blower, adjust for external static pressure as follows:
    Step (1) Operate the unit under conditions specified for the 
B1 test using the certified fan speed or controls 
settings, and adjust the exhaust fan of the airflow measuring 
apparatus to achieve the certified cooling minimum air volume rate;
    Step (2) Measure the external static pressure;
    Step (3) If this pressure is equal to or greater than the 
minimum external static pressure computed in step 2 of this section, 
the pressure requirement is satisfied; proceed to step 7 of this 
section. If this pressure is not equal to or greater than the 
minimum external static pressure computed in step 2 of this section, 
proceed to step 4 of this section;
    Step (4) Increase the external static pressure by adjusting the 
exhaust fan of the airflow measuring apparatus until either:

[[Page 64590]]

    (i) The pressure is equal to the target minimum external static 
pressure, [Delta]Pst_i, computed in step 1 of this 
section; or
    (ii) The measured air volume rate equals 90 percent or less of 
the cooling minimum air volume rate, whichever occurs first;
    Step (5) If the conditions of step 4 (i) of this section occur 
first, the pressure requirement is satisfied; proceed to step 7 of 
this section. If the conditions of step 4 (ii) of this section occur 
first, proceed to step 6 of this section;
    Step (6) Make an incremental change to the setup of the indoor 
blower (e.g., next highest fan motor pin setting, next highest fan 
motor speed) and repeat the evaluation process beginning at step 1 
of this section. If the indoor blower setup cannot be further 
changed, increase the external static pressure by adjusting the 
exhaust fan of the airflow measuring apparatus until it equals the 
minimum external static pressure computed in step 2 of this section; 
proceed to step 7 of this section;
    Step (7) The airflow constraints have been satisfied. Use the 
measured air volume rate as the cooling minimum air volume rate. Use 
the final indoor fan speed or control settings of the unit under 
test for all tests that use the cooling minimum air volume rate. 
Adjust the fan of the airflow measurement apparatus if needed to 
obtain the same cooling minimum air volume rate (in scfm) for all 
such tests, unless the system modulates the indoor blower speed with 
outdoor dry bulb temperature or to adjust the sensible to total 
cooling capacity ratio--in this case, use an air volume rate that 
represents a normal installation and calculate the target minimum 
external static pressure as described in this section.
    b. For ducted units with constant-air-volume indoor blowers, 
conduct all tests that specify the cooling minimum air volume rate--
(i.e., the A1, B1, C1, 
F1, and G1 Tests)--at an external static 
pressure that does not cause either an automatic shutdown of the 
indoor blower or a value of air volume rate variation 
QVar, defined in section 3.1.4.1.1.b of this appendix, 
that is greater than 10 percent, while being as close to, but not 
less than the target minimum external static pressure. Additional 
test steps as described in section 3.3.f of this appendix are 
required if the measured external static pressure exceeds the target 
value by more than 0.03 inches of water.
* * * * *
    f. For ducted variable-speed compressor systems tested with a 
coil-only indoor unit, the cooling minimum air volume rate is the 
higher of:
    (1) The rate specified by the installation instructions included 
with the unit by the manufacturer; or
    (2) 75 percent of the cooling full-load air volume rate. During 
the laboratory tests on a coil-only (fanless) system, obtain this 
cooling minimum air volume rate regardless of the pressure drop 
across the indoor coil assembly.

3.1.4.3 Cooling Intermediate Air Volume Rate

* * * * *
    b. For a ducted blower-coil system with a constant-air-volume 
indoor blower, conduct the EV Test at an external static 
pressure that does not cause either an automatic shutdown of the 
indoor blower or a value of air volume rate variation 
QVar, defined in section 3.1.4.1.1.b of this appendix, 
that is greater than 10 percent, while being as close to, but not 
less than the target minimum external static pressure. Additional 
test steps as described in section 3.3.f of this appendix are 
required if the measured external static pressure exceeds the target 
value by more than 0.03 inches of water.
* * * * *
    d. For ducted variable-speed compressor systems tested with a 
coil-only indoor unit, use the cooling minimum air volume rate as 
determined in section 3.1.4.2(f) of this appendix, without regard to 
the pressure drop across the indoor coil assembly.
* * * * *

3.1.4.4.3 Ducted Heating-Only Heat Pumps

* * * * *
    a. For all ducted heating-only blower-coil system heat pumps, 
except those having a constant-air-volume-rate indoor blower: 
conduct the following steps only during the first test, the H1 or 
H12 test:
    Step (1) Adjust the exhaust fan of the airflow measuring 
apparatus to achieve the certified heating full-load air volume 
rate.
    Step (2) Measure the external static pressure.
    Step (3) If this pressure is equal to or greater than the Table 
4 to this appendix minimum external static pressure that applies 
given the heating-only heat pump's rated heating capacity, the 
pressure requirement is satisfied; proceed to step 7 of this 
section. If this pressure is not equal to or greater than the 
applicable Table 4 minimum external static pressure, proceed to step 
4 of this section;
    Step (4) Increase the external static pressure by adjusting the 
exhaust fan of the airflow measuring apparatus until either:
    (i) The pressure is equal to the applicable Table 4 to this 
appendix minimum external static pressure; or
    (ii) The measured air volume rate equals 90 percent or less of 
the heating full-load air volume rate, whichever occurs first;
    Step (5) If the conditions of step 4 (i) of this section occur 
first, the pressure requirement is satisfied; proceed to step 7 of 
this section. If the conditions of step 4 (ii) of this section occur 
first, proceed to step 6 of this section;
    Step (6) Make an incremental change to the setup of the indoor 
blower (e.g., next highest fan motor pin setting, next highest fan 
motor speed) and repeat the evaluation process beginning at step 1 
of this section. If the indoor blower setup cannot be further 
changed, increase the external static pressure by adjusting the 
exhaust fan of the airflow measuring apparatus until it equals the 
applicable Table 4 to this appendix minimum external static 
pressure; proceed to step 7 of this section;
    Step (7) The airflow constraints have been satisfied. Use the 
measured air volume rate as the heating full-load air volume rate. 
Use the final indoor fan speed or control settings of the unit under 
test for all tests that use the heating full-load air volume rate. 
Adjust the fan of the airflow measurement apparatus if needed to 
obtain the same heating full-load air volume rate (in scfm) for all 
such tests, unless the system modulates indoor blower speed with 
outdoor dry bulb temperature--in this case, use an air volume rate 
that represents a normal installation and calculate the target 
minimum external static pressure as described in section 3.1.4.2 of 
this appendix.
* * * * *

3.1.4.6 Heating Intermediate Air Volume Rate

* * * * *
    d. For ducted variable-speed compressor systems tested with a 
coil-only indoor unit, use the heating minimum air volume rate, 
which (as specified in section 3.1.4.5.1.a.(3) of this appendix) is 
equal to the cooling minimum air volume rate, without regard to the 
pressure drop across the indoor coil assembly.

3.1.4.7 Heating Nominal Air Volume Rate

    The manufacturer must specify the heating nominal air volume 
rate and the instructions for setting fan speed or controls. 
Calculate target minimum external static pressure as described in 
section 3.1.4.2 of this appendix. Make adjustments as described in 
section 3.1.4.6 of this appendix for heating intermediate air volume 
rate so that the target minimum external static pressure is met or 
exceeded. For ducted variable-speed compressor systems tested with a 
coil-only indoor unit, use the heating full-load air volume rate as 
the heating nominal air volume rate.
* * * * *

3.2.4 Tests for a Unit Having a Variable-Speed Compressor

    a. Conduct five steady-state wet coil tests: the A2, 
EV, B2, B1, and F1 Tests 
(the EV test is not applicable for variable speed non-
communicating coil-only air conditioners and heat pumps). Use the 
two optional dry-coil tests, the steady-state G1 Test and 
the cyclic I1 Test, to determine the cooling mode cyclic 
degradation coefficient, CD\c\. If the two optional tests 
are conducted and yield a tested CD\c\ that exceeds the 
default CD\c\ or if the two optional tests are not 
conducted, assign CD\c\ the default value of 0.25. Table 
8 specifies test conditions for these seven tests. The compressor 
shall operate at the same cooling full speed, measured by RPM or 
power input frequency (Hz), for both the A2 and 
B2 tests. The compressor shall operate at the same 
cooling minimum speed, measured by RPM or power input frequency 
(Hz), for the B1, F1, G1, and 
I1 tests. Determine the cooling intermediate compressor 
speed cited in Table 8 to this appendix, as required, using:

[[Page 64591]]

[GRAPHIC] [TIFF OMITTED] TR25OC22.022

Where a tolerance of plus 5 percent or the next higher inverter 
frequency step from that calculated is allowed.
* * * * *
    d. For variable-speed non-communicating coil-only air 
conditioners and heat pumps, the manufacturer-provided equipment 
overrides for full and minimum compressor speed described in section 
3.1.2 of this appendix shall be limited to two stages of digital on/
off control.

                                    Table 8--Cooling Mode Test Condition for Units Having a Variable-Speed Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Air entering indoor unit        Air entering outdoor unit
                                            temperature ([deg]F)            temperature ([deg]F)
           Test description           ----------------------------------------------------------------     Compressor speed      Cooling air volume rate
                                          Dry bulb        Wet bulb        Dry bulb        Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
A2 Test--required (steady, wet coil).              80              67              95           \1\75  Cooling Full............  Cooling Full-Load.\2\
B2 Test--required (steady, wet coil).              80              67              82           \1\65  Cooling Full............  Cooling Full-Load.\2\
EV Test--required \7\ (steady, wet                 80              67              87           \1\69  Cooling Intermediate....  Cooling
 coil).                                                                                                                           Intermediate.\3\
B1 Test--required (steady, wet coil).              80              67              82           \1\65  Cooling Minimum.........  Cooling Minimum.\4\
F1 Test--required (steady, wet coil).              80              67              67         \1\53.5  Cooling Minimum.........  Cooling Minimum.\4\
G1 Test \5\--optional (steady, dry-                80           (\6\)              67  ..............  Cooling Minimum.........  Cooling Minimum.\4\
 coil).
I1 Test \5\--optional (cyclic, dry-                80           (\6\)              67  ..............  Cooling Minimum.........  (\6\)
 coil).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The specified test condition only applies if the unit rejects condensate to the outdoor coil.
\2\ Defined in section 3.1.4.1 of this appendix.
\3\ Defined in section 3.1.4.3 of this appendix.
\4\ Defined in section 3.1.4.2 of this appendix.
\5\ The entering air must have a low enough moisture content so no condensate forms on the indoor coil. DOE recommends using an indoor air wet bulb
  temperature of 57 [deg]F or less.
\6\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure difference or velocity
  pressure as measured during the G1 Test.
\7\ The EV test is not applicable for variable-speed non-communicating coil-only air conditioners and heat pumps.

* * * * *

3.3 Test Procedures for Steady-State Wet Coil Cooling Mode Tests (the 
A, A2, A1, B, B2, B1, 
EV, and F1 Tests)

* * * * *
    d. For mobile home and space-constrained ducted coil-only system 
tests,
    (1) For two-stage or variable-speed systems, for all steady-
state wet coil tests (i.e., the A1, A2, 
B1, B2, EV, and F1 
tests), decrease by the quantity calculated in Equation 3.3-1 to 
this appendix and increase by the quantity calculated in Equation 
3.3-2 to this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.023

Where:

DFPCMHSC is the default fan power coefficient (watts) for 
mobile-home and space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.024


[[Page 64592]]


And %FLAVR is the air volume rate used for the test, expressed as a 
percentage of the cooling full load air volume rate. For all tests 
specifying the full-load air volume rate (e.g., the A2 
and B2 tests), set %FLAVR to 100%. For tests that specify 
the cooling minimum air volume rate or cooling intermediate air 
volume rate (i.e., the A1, B1, EV, 
and F1 tests) and for which the specified minimum or 
intermediate air volume rate is greater than or equal to 75 percent 
of the cooling full-load air volume rate and less than the cooling 
full-load air volume rate, set %FLAVR to the ratio of the specified 
air volume rate and the cooling full-load air volume rate, expressed 
as a percentage.
    (2) For single-stage systems, for all steady-state wet coil 
tests (i.e., the A and B tests), decrease Qc\k\(T) by the 
quantity calculated in Equation 3.3-3 to this appendix and increase 
Ec\k\(T) by the quantity calculated in Equation 3.3-4 to 
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.025

Where VS is the average measured indoor air volume rate 
expressed in units of cubic feet per minute of standard air (scfm).

    e. For non-mobile, non-space-constrained home ducted coil-only 
system tests,
    (1) For two-stage or variable-speed systems, for all steady-
state wet coil tests (i.e., the A1, A2, 
B1, B2, EV, and F1 
tests), decrease Qc\k\(T) by the quantity calculated in 
Equation 3.3-5 to this appendix and increase Ec\k\(T) by 
the quantity calculated in Equation 3.3-6 to this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.026

[GRAPHIC] [TIFF OMITTED] TR25OC22.027

Where:

DFPCC is the default fan power coefficient (watts) for 
non-mobile-home and non-space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.028

    And %FLAVR is the air volume rate used for the test, expressed 
as a percentage of the cooling full load air volume rate. For all 
tests specifying the full-load air volume rate (e.g., the 
A2 and B2 tests), set %FLAVR to 100%. For 
tests that specify the cooling minimum air volume rate or cooling 
intermediate air volume rate (i.e., the A1, 
B1, EV, and F1 tests) and for which 
the specified minimum or intermediate air volume rate is greater 
than or equal to 75 percent of the cooling full-load air volume rate 
and less than the cooling full-load air volume rate, set %FLAVR to 
the ratio of the specified air volume rate and the cooling full-load 
air volume rate, expressed as a percentage.
    (2) For single-stage systems, for all steady-state wet coil 
tests (i.e., the A and B tests), decrease Qc\k\(T) by the 
quantity calculated in Equation 3.3-7 to this appendix and increase 
Ec\k\(T) by the quantity calculated in Equation 3.3-8 to 
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.029

[GRAPHIC] [TIFF OMITTED] TR25OC22.030

Where is the average measured indoor air volume rate expressed in 
units of cubic feet per minute of standard air (scfm).


[[Page 64593]]



  Table 9--Test Operating and Test Condition Tolerances for Section 3.3
    Steady-State Wet Coil Cooling Mode Tests and Section 3.4 Dry Coil
                           Cooling Mode Tests
------------------------------------------------------------------------
                                          Test operating  Test condition
                                           tolerance \1\   tolerance \1\
------------------------------------------------------------------------
Indoor dry-bulb, [deg]F
    Entering temperature................             2.0             0.5
    Leaving temperature.................             2.0  ..............
Indoor wet-bulb, [deg]F                   ..............  ..............
    Entering temperature................             1.0         \2\ 0.3
    Leaving temperature.................         \2\ 1.0  ..............
Outdoor dry-bulb, [deg]F
    Entering temperature................             2.0             0.5
    Leaving temperature.................         \3\ 2.0  ..............
Outdoor wet-bulb, [deg]F
    Entering temperature................             1.0         \4\ 0.3
    Leaving temperature.................         \3\ 1.0  ..............
External resistance to airflow, inches              0.05        \5\ 0.02
 of water...............................
Electrical voltage, % of reading........             2.0             1.5
Nozzle pressure drop, % of reading......             2.0  ..............
------------------------------------------------------------------------
\1\ See section 1.2 of this appendix, Definitions.
\2\ Only applies during wet coil tests; does not apply during steady-
  state, dry coil cooling mode tests.
\3\ Only applies when using the outdoor air enthalpy method.
\4\ Only applies during wet coil cooling mode tests where the unit
  rejects condensate to the outdoor coil.
\5\ Only applies when testing non-ducted units.

* * * * *

3.5.1 Procedures When Testing Ducted Systems

    The automatic controls that are installed in the test unit must 
govern the OFF/ON cycling of the air moving equipment on the indoor 
side (i.e., the exhaust fan of the airflow measuring apparatus and 
the indoor blower of the test unit). For ducted coil-only systems 
rated based on using a fan time-delay relay, control the indoor coil 
airflow according to the OFF delay listed by the manufacturer in the 
certification report. For ducted units having a variable-speed 
indoor blower that has been disabled (and possibly removed), start 
and stop the indoor airflow at the same instances as if the fan were 
enabled. For all other ducted coil-only systems, cycle the indoor 
coil airflow in unison with the cycling of the compressor. If air 
damper boxes are used, close them on the inlet and outlet side 
during the OFF period. Airflow through the indoor coil should stop 
within 3 seconds after the automatic controls of the test unit de-
energize (or if the airflow system has been disabled (and possibly 
removed), within 3 seconds after the automatic controls of the test 
unit would have de-energized) the indoor blower.
    a. For mobile home and space-constrained ducted coil-only 
systems,
    (1) For two-stage or variable-speed systems, for all cyclic dry-
coil tests (i.e., the D1, D2, and 
I1 tests) decrease qcyc,dry by the quantity 
calculated in Equation 3.5-2 to this appendix and increase 
ecyc,dry by the quantity calculated in Equation 3.5-3 to 
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.031

[GRAPHIC] [TIFF OMITTED] TR25OC22.032

Where:

VS is the average indoor air volume rate from the section 
3.4 dry coil steady-state test and is expressed in units of cubic 
feet per minute of standard air (scfm),

DFPCMHSC is the default fan power coefficient (watts) for 
mobile-home and space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.033

And %FLAVR is the air volume rate used for the test, expressed as a 
percentage of the cooling full load air volume rate. For all tests 
specifying the full-load air volume rate (e.g., the D2 
test), set %FLAVR to 100%. For tests that specify the cooling 
minimum air volume rate or cooling intermediate air volume rate 
(i.e., the D1 and I1 tests) and for which the 
specified minimum or intermediate air volume rate is greater than or 
equal to 75 percent of the cooling full-load air volume rate and 
less than the cooling full-load air volume rate, set %FLAVR to the 
ratio of the specified air volume rate and the cooling full-load air 
volume rate, expressed as a percentage.

    (2) For single-stage systems, for all cyclic dry-coil tests 
(i.e., the D test), decrease qcyc,dry by the quantity 
calculated in Equation 3.5-4 to this appendix and increase 
ecyc,dry by the quantity calculated in Equation 3.5-5 to 
this appendix.

[[Page 64594]]

[GRAPHIC] [TIFF OMITTED] TR25OC22.034

[GRAPHIC] [TIFF OMITTED] TR25OC22.035

    b. For ducted, non-mobile, non-space-constrained home coil-only 
units,
    (1) For two-stage or variable-speed systems, for all cyclic dry-
coil tests (i.e., the D1, D2, and 
I1 tests) decrease qcyc,dry by the quantity 
calculated in Equation 3.5-6 to this appendix and increase 
ecyc,dry by the quantity calculated in Equation 3.5-7 to 
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.036

Where:

VS is the average indoor air volume rate from the section 
3.4 dry coil steady-state test and is expressed in units of cubic 
feet per minute of standard air (scfm),
DFPCC is the default fan power coefficient (watts) for 
non-mobile-home and non-space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.037

And %FLAVR is the air volume rate used for the test, expressed as a 
percentage of the cooling full load air volume rate. For all tests 
specifying the full-load air volume rate (e.g., the D2 
test), set %FLAVR to 100%. For tests that specify the cooling 
minimum air volume rate or cooling intermediate air volume rate 
(i.e., the D1, and I1 tests) and for which the 
specified minimum or intermediate air volume rate is greater than or 
equal to 75 percent of the cooling full-load air volume rate and 
less than the cooling full-load air volume rate, set %FLAVR to the 
ratio of the specified air volume rate and the cooling full-load air 
volume rate, expressed as a percentage.
    (2) For single-stage systems, for all cyclic dry-coil tests 
(i.e., the D test) decrease qcyc,dry by the quantity 
calculated in Equation 3.5-8 to this appendix and increase 
ecyc,dry by the quantity calculated in Equation 3.5-9 to 
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.038

[GRAPHIC] [TIFF OMITTED] TR25OC22.039

    c. For units having a variable-speed indoor blower that is 
disabled during the cyclic test, decrease qcyc,dry and 
increase ecyc,dry based on: The product of 
[[tau]2 - [tau]1] and the indoor blower power 
(in W) measured during or following the dry coil steady-state test; 
or,
* * * * *

3.6.1 Tests for a Heat Pump Having a Single-Speed Compressor and Fixed 
Heating Air Volume Rate

* * * * *


   Table 11--Heating Mode Test Conditions for Units Having a Single-Speed Compressor and a Fixed-Speed Indoor
                         Blower, a Constant Air Volume Rate Indoor Blower, or Coil-Only
----------------------------------------------------------------------------------------------------------------
                                   Air entering indoor unit        Air entering outdoor unit
                                     temperature ([deg]F)             temperature ([deg]F)         Heating air
       Test description       ------------------------------------------------------------------   volume rate
                                  Dry bulb         Wet bulb        Dry bulb         Wet bulb
----------------------------------------------------------------------------------------------------------------
H1 test (required, steady)...              70  60\(max)\......              47  43.............  Heating Full-
                                                                                                  Load.\1\
H1C test (optional, cyclic)..              70  60\(max)\......              47  43.............  (\2\)
H2 test (required)...........              70  60\(max)\......              35  33.............  Heating Full-
                                                                                                  Load.\1\
H3 test (required, steady)...              70  60\(max)\......              17  15.............  Heating Full-
                                                                                                  Load.\1\
H4 test (optional, steady)...              70  60\(max)\......               5  4\(max)\.......  Heating Full-
                                                                                                  Load.\1\
----------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.4 of this appendix.
\2\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the
  same pressure or velocity as measured during the H1 test.


[[Page 64595]]

* * * * *

3.6.2 Tests for a Heat Pump Having a Single-Speed Compressor and a 
Single Indoor Unit Having Either (1) a Variable-Speed, Variable-Air-
Rate Indoor Blower Whose Capacity Modulation Correlates With Outdoor 
Dry Bulb Temperature or (2) Multiple Indoor Blowers

* * * * *

   Table 12--Heating Mode Test Conditions for Units With a Single-Speed Compressor That Meet the Section 3.6.2
                                            Indoor Unit Requirements
----------------------------------------------------------------------------------------------------------------
                                   Air entering indoor unit        Air entering outdoor unit
                                     temperature ([deg]F)             temperature ([deg]F)         Heating air
       Test description       ------------------------------------------------------------------   volume rate
                                  Dry bulb         Wet bulb        Dry bulb         Wet bulb
----------------------------------------------------------------------------------------------------------------
H12 test (required, steady)..              70  60\(max)\......              47  43.............  Heating Full-
                                                                                                  Load.\1\
H11 test (required, steady)..              70  60\(max)\......              47  43.............  Heating
                                                                                                  Minimum.\2\
H1C1 test (optional, cyclic).              70  60\(max)\......              47  43.............  (\3\)
H22 test (required)..........              70  60\(max)\......              35  33.............  Heating Full-
                                                                                                  Load.\1\
H21 test (optional)..........              70  60\(max)\......              35  33.............  Heating
                                                                                                  Minimum.\2\
H32 test (required, steady)..              70  60\(max)\......              17  15.............  Heating Full-
                                                                                                  Load.\1\
H31 test (required, steady)..              70  60\(max)\......              17  15.............  Heating
                                                                                                  Minimum.\2\
H42 test (optional, steady)..              70  60\(max)\......               5  4\(max)\.......  Heating Full-
                                                                                                  Load.\1\
----------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.4 of this appendix.
\2\ Defined in section 3.1.4.5 of this appendix.
\3\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the
  same pressure or velocity as measured during the H11 test.

* * * * *

3.6.3 Tests for a Heat Pump Having a Two-Capacity Compressor (see 
Section 1.2 of This Appendix, Definitions), Including Two-Capacity, 
Northern Heat Pumps (see Section 1.2 of This Appendix, Definitions)

* * * * *

                                    Table 13--Heating Mode Test Conditions for Units Having a Two-Capacity Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                         Air entering indoor unit            Air entering outdoor unit
                                           temperature ([deg]F)                temperature ([deg]F)                                  Heating air volume
         Test description          ------------------------------------------------------------------------  Compressor capacity            rate
                                      Dry bulb          Wet bulb          Dry bulb          Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 test (required, steady).......           70  60\(max)\............           62  56.5.................  Low..................  Heating Minimum.\1\
H12 test (required, steady).......           70  60\(max)\............           47  43...................  High.................  Heating Full-Load.\2\
H1C2 test (optional,\7\ cyclic)...           70  60\(max)\............           47  43...................  High.................  (\3\)
H11 test (required, steady).......           70  60\(max)\............           47  43...................  Low..................  Heating Minimum.\1\
H1C1 test (optional, cyclic)......           70  60\(max)\............           47  43...................  Low..................  (\4\)
H22 test (required)...............           70  60\(max)\............           35  33...................  High.................  Heating Full-Load.\2\
H21 test 5 6 (required)...........           70  60\(max)\............           35  33...................  Low..................  Heating Minimum.\1\
H32 test (required, steady).......           70  60\(max)\............           17  15...................  High.................  Heating Full-Load.\2\
H31 test \5\ (required, steady)...           70  60\(max)\............           17  15...................  Low..................  Heating Minimum.\1\
H42 test (optional, steady).......           70  60\(max)\............            5  4\(max)\.............  High.................  Heating Full-Load.\2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5 of this appendix.
\2\ Defined in section 3.1.4.4 of this appendix.
\3\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the same pressure or velocity as measured
  during the H12 test.
\4\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the same pressure or velocity as measured
  during the H11 test.
\5\ Required only if the heat pump's performance when operating at low compressor capacity and outdoor temperatures less than 37[deg]F is needed to
  complete HSPF2 calculations in section 4.2.3 of this appendix.
\6\ If note #5 to this table applies, the equations for Q h\k=1\ (35) and E h\k=1\ (17) in section 3.6.3 of this appendix may be used in lieu of
  conducting the H21 test.
\7\ Required only if the heat pump locks out low-capacity operation at lower outdoor temperatures.


[[Page 64596]]

* * * * *

3.6.4 Tests for a Heat Pump Having a Variable-Speed Compressor

3.6.4.1 Variable-Speed Compressor Other Than Non-Communicating Coil-
Only Heat Pumps

    a. Conduct one maximum temperature test (H01), two 
high temperature tests (H1N and H11), one 
frost accumulation test (H2V), and one low temperature 
test (H32). Conducting one or more of the following tests 
is optional: an additional high temperature test (H12), 
an additional frost accumulation test (H22), and a very 
low temperature test (H42). Conduct the optional high 
temperature cyclic (H1C1) test to determine the heating 
mode cyclic-degradation coefficient, CD\h\. If this 
optional test is conducted and yields a tested CD\h\ that 
exceeds the default CD\h\ or if the optional test is not 
conducted, assign CD\h\ the default value of 0.25. Test 
conditions for the nine tests are specified in Table 14A to this 
appendix. The compressor shall operate for the H12, 
H22 and H32 Tests at the same heating full 
speed, measured by RPM or power input frequency (Hz), as the maximum 
speed at which the system controls would operate the compressor in 
normal operation in 17[deg]F ambient temperature. The compressor 
shall operate for the H1N test at the maximum speed at 
which the system controls would operate the compressor in normal 
operation in 47[deg]F ambient temperature. Additionally, for a 
cooling/heating heat pump, the compressor shall operate for the 
H1N test at a speed, measured by RPM or power input 
frequency (Hz), no lower than the speed used in the A2 
test if the tested H1N heating capacity is less than the 
tested A2 cooling capacity. The compressor shall operate 
at the same heating minimum speed, measured by RPM or power input 
frequency (Hz), for the H01, H1C1, and 
H11 Tests. Determine the heating intermediate compressor 
speed cited in Table 14A using the heating mode full and minimum 
compressors speeds and:
[GRAPHIC] [TIFF OMITTED] TR25OC22.040

Where a tolerance of plus 5 percent or the next higher inverter 
frequency step from that calculated is allowed.

    b. If one of the high temperature tests (H12 or 
H1N) is conducted using the same compressor speed (RPM or 
power input frequency) as the H32 test, set the 47[deg]F 
capacity and power input values used for calculation of HSPF2 equal 
to the measured values for that test:

Qk=2hcalc(47) = Qk=2h(47); 
Ek=2hcalc(47) = E\k=2\h(47)
Where:

Q\k=2\hcalc(47) and E\k=2\hcalc(47) are the capacity and power 
input, respectively, representing full-speed operation at 47 [deg]F 
for the HSPF2 calculations,
Q\k=2\h(47) is the capacity measured in the high temperature test 
(H12 or H1N) that used the same compressor 
speed as the H32 test, and
E\k=2\h(47) is the power input measured in the high temperature test 
(H12 or H1N) which used the same compressor 
speed as the H32 test.

    Evaluate the quantities Q\h\k=2(47) and Ehk=2(47) 
according to section 3.7 of this appendix.
    Otherwise (if no high temperature test is conducted using the 
same speed (RPM or power input frequency) as the H32 
test), calculate the 47 [deg]F capacity and power input values used 
for calculation of HSPF2 as follows:

Q\k=2\hcalc(47) = Q\k=2\h(17) * (1 + 30[deg]F * CSF);
E\k=2\hcalc(47) = E\k=2\h(17) * (1 + 30[deg]F * PSF);

Where:

Q\k=2\hcalc(47) and E\k=2\hcalc(47) are the capacity and power 
input, respectively, representing full-speed operation at 47 [deg]F 
for the HSPF2 calculations,
Q\k=2\h(17) is the capacity measured in the H32 test,
E\k=2\h(17) is the power input measured in the H32 test,
CSF is the capacity slope factor, equal to 0.0204/[deg]F for split 
systems and 0.0262/[deg]F for single-package systems, and
PSF is the Power Slope Factor, equal to 0.00455/[deg]F.
    c. If the H22 test is not done, use the following 
equations to approximate the capacity and electrical power at the 
H22 test conditions:

Q\k=2\h(35) = 0.90*{Q\k=2\h(17) + 
0.6*[Q\k=2\hcalc(47) - Q\k=2\h(17)]{time} 
E\k=2\h(35) = 0.985*{E\k=2\h(17) + 
0.6*[E\k=2\hcalc(47) - E\k=2\h(17)]{time} 

Where:

Q\k=2\hcalc(47) and E\k=2\hcalc(47) are the 
capacity and power input, respectively, representing full-speed 
operation at 47 [deg]F for the HSPF2 calculations, calculated as 
described in paragraph b. of this section, and
Q\k=2\h(17) and E\k=2\h(17) are the capacity 
and power input measured in the H32 test.

    d. Determine the quantities Qh\k=2\(17) and 
Eh\k=2\(17) from the H32 test, determine the 
quantities Qh\k=2\(5) and Eh\k=2\(5) from the 
H42 test, and evaluate all four according to section 3.10 
of this appendix.
    e. For multiple-split heat pumps (only), the following 
procedures supersede the above requirements. For all Table 14A of 
this appendix tests specified for a minimum compressor speed, turn 
off at least one indoor unit. The manufacturer shall designate the 
particular indoor unit(s) to be turned off. The manufacturer must 
also specify the compressor speed used for the Table 14A 
H2V test, a heating mode intermediate compressor speed 
that falls within \1/4\ and \3/4\ of the difference between the full 
and minimum heating mode speeds. The manufacturer should prescribe 
an intermediate speed that is expected to yield the highest COP for 
the given H2V test conditions and bracketed compressor 
speed range. The manufacturer can designate that one or more 
specific indoor units are turned off for the H2V test.

  Table 14A--Heating Mode Test Conditions for Units Having a Variable-Speed Compressor Other Than Variable-Speed Non-Communicating Coil-Only Heat Pumps
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                   Air entering indoor unit temperature        Air entering outdoor unit
                                                 ([deg]F)                        temperature ([deg]F)                                 Heating air volume
         Test description         ----------------------------------------------------------------------------   Compressor speed            rate
                                      Dry bulb           Wet bulb           Dry bulb           Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 test (required, steady)......              70  60\(max)\...........              62  56.5................  Heating Minimum.....  Heating Minimum.\1\
H12 test (optional, steady)......              70  60\(max)\...........              47  43..................  Heating Full \4\....  Heating Full-
                                                                                                                                      Load.\3\
H11 test (required, steady)......              70  60\(max)\...........              47  43..................  Heating Minimum.....  Heating Minimum.\1\
H1N test (required, steady)......              70  60\(max)\...........              47  43..................  Heating Full \5\....  Heating Nominal.\7\
H1C1 test (optional, cyclic).....              70  60\(max)\...........              47  43..................  Heating Minimum.....  (\2\)
H22 test (optional)..............              70  60\(max)\...........              35  33..................  Heating Full \4\....  Heating Full-
                                                                                                                                      Load.\3\
H2V test (required)..............              70  60\(max)\...........              35  33..................  Heating Intermediate  Heating
                                                                                                                                      Intermediate.\6\

[[Page 64597]]

 
H32 test (required, steady)......              70  60\(max)\...........              17  15..................  Heating Full \4\....  Heating Full-
                                                                                                                                      Load.\3\
H42 test (optional, steady)......              70  60\(max)\...........               5  4\(max)\............  Heating Full \8\....  Heating Full-
                                                                                                                                      Load.\3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5 of this appendix.
\2\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the same pressure or velocity as measured
  during the H11 test.
\3\ Defined in section 3.1.4.4 of this appendix.
\4\ Maximum speed that the system controls would operate the compressor in normal operation in 17[deg]F ambient temperature. The H12 test is not needed
  if the H1N test uses this same compressor speed.
\5\ Maximum speed that the system controls would operate the compressor in normal operation in 47[deg]F ambient temperature.
\6\ Defined in section 3.1.4.6 of this appendix.
\7\ Defined in section 3.1.4.7 of this appendix.
\8\ Maximum speed that the system controls would operate the compressor in normal operation at 5[deg]F ambient temperature.

3.6.4.2 Variable-Speed Compressor With Non-Communicating Coil-Only Heat 
Pumps

    a. Conduct one maximum temperature test (H01), two 
high temperature tests (H1N and H11), two 
frost accumulation test (H22 and H21), and two 
low temperature tests (H32 and H31). 
Conducting one or both of the following tests is optional: an 
additional high temperature test (H12) and a very low 
temperature test (H42). Conduct the optional high 
temperature cyclic (H1C1) test to determine the heating 
mode cyclic-degradation coefficient, CD\h\. If this 
optional test is conducted and yields a tested CD\h\ that 
exceeds the default CD\h\ or if the optional test is not 
conducted, assign CD\h\ the default value of 0.25. Test 
conditions for the ten tests are specified in Table 14B to this 
appendix. The compressor shall operate for the H12 and 
H32 tests at the same heating full speed, measured by RPM 
or power input frequency (Hz), as the maximum speed at which the 
system controls would operate the compressor in normal operation in 
17 [deg]F ambient temperature. The compressor shall operate for the 
H1N test at the maximum speed at which the system 
controls would operate the compressor in normal operation in 47 
[deg]F ambient temperature. Additionally, for a cooling/heating heat 
pump, the compressor shall operate for the H1N test at a 
speed, measured by RPM or power input frequency (Hz), no lower than 
the speed used in the A2 test if the tested 
H1N heating capacity is less than the tested 
A2 cooling capacity. The compressor shall operate at the 
same heating minimum speed, measured by RPM or power input frequency 
(Hz), for the H01, H1C1, and H11 
tests.
    b. If one of the high temperature tests (H12 or 
H1N) is conducted using the same compressor speed (RPM or 
power input frequency) as the H32 test, set the 47 [deg]F 
capacity and power input values used for calculation of HSPF2 equal 
to the measured values for that test:

Qk=2hcalc(47) = Qk=2h(47) = Ek=\2\hcalc(47) = Ek=2h(47)

Where:

Qk=\2\hcalc(47) and Ek=\2\hcalc(47) are the 
capacity and power input, respectively, representing full-speed 
operation at 47 [deg]F for the HSPF2 calculations,
Qk=2h(47) is the capacity measured in the high 
temperature test (H12 or H1N) which used the 
same compressor speed as the H32 test, and
Ek=2h(47) is the power input measured in the high 
temperature test (H12 or H1N) which used the 
same compressor speed as the H32 test.

    Evaluate the quantities Qh=\2\(47) and 
Ek=\2\(47) according to section 3.7 of this appendix.
    Otherwise (if no high temperature test is conducted using the 
same speed (RPM or power input frequency) as the H32 
test), calculate the 47 [deg]F capacity and power input values used 
for calculation of HSPF2 as follows:

Qk=2hcalc(47) = Qk=2h(17) * (1 + 30 [deg]F CSF); and
Ek=2hcalc(47) = Ek=2h(17) * (1 + 30 [deg]F PSF); and

Where:

Qk=2hcalc and Ek=2hcalc(47) are the capacity and power input, 
respectively, representing full-speed operation at 47 [deg]F for the 
HSPF2 calculations,
Qk=2h is the capacity measured in the H32 test,
Ek=2h(47) is the power input measured in the H32 test,

    CSF is the capacity slope factor, equal to 0.0204/ [deg]F for 
split systems, and
    PSF is the Power Slope Factor, equal to 0.00455/ [deg]F.
    c. Determine the quantities Qk=\2\h(17) and 
Ek=\2\h(5) from the H32 test, determine the 
quantities Qk=\2\h(5) and Ek=\2\h(5) from the 
H42 test, and evaluate all four according to section 3.10 
of this appendix.

                            Table 14B--Heating Mode Test Conditions for Variable-Speed Non-Communicating Coil-Only Heat Pumps
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                   Air entering indoor unit temperature        Air entering outdoor unit
                                                 ( [deg]F)                       temperature ( [deg]F)                                Heating air volume
         Test description         ----------------------------------------------------------------------------   Compressor speed            rate
                                      Dry bulb           Wet bulb           Dry bulb           Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 test (required, steady)......              70  60 (max)............              62  56.5................  Heating Minimum.....  Heating Minimum.\1\
H12 test (optional, steady)......              70  60 (max)............              47  43..................  Heating Full \4\....  Heating Full-
                                                                                                                                      Load.\3\
H11 test (required, steady)......              70  60 (max)............              47  43..................  Heating Minimum.....  Heating Minimum.\1\
H1N test (required, steady)......              70  60 (max)............              47  43..................  Heating Full \5\....  Heating Full-
                                                                                                                                      Load.\3\
H1C1 test (optional, cyclic).....              70  60 (max)............              47  43..................  Heating Minimum.....  (\2\)
H22 test (required)..............              70  60 (max)............              35  33..................  Heating Full \6\....  Heating Full-
                                                                                                                                      Load.\3\
H21 test (required)..............              70  60 (max)............              35  33..................  Heating Minimum \7\.  Heating Minimum.\1\
H32 test (required, steady)......              70  60 (max)............              17  15..................  Heating Full \4\....  Heating Full-
                                                                                                                                      Load.\3\
H31 test (required, steady)......              70  60 (max)............              17  15..................  Heating Minimum \8\.  Heating Minimum.\1\
H42 test (optional, steady)......              70  60 (max)............               5  4 (max).............  Heating Full \9\....  Heating Full-
                                                                                                                                      Load.\3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5 of this appendix.
\2\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the same pressure or velocity as measured
  during the H11 test.
\3\ Defined in section 3.1.4.4 of this appendix.
\4\ Maximum speed that the system controls would operate the compressor in normal operation in 17 [deg]F ambient temperature. The H12 test is not needed
  if the H1N test uses this same compressor speed.
\5\ Maximum speed that the system controls would operate the compressor in normal operation in 47 [deg]F ambient temperature.
\6\ Maximum speed that the system controls would operate the compressor in normal operation in 35 [deg]F ambient temperature.
\7\ Minimum speed that the system controls would operate the compressor in normal operation in 35 [deg]F ambient temperature.
\8\ Minimum speed that the system controls would operate the compressor in normal operation in 17 [deg]F ambient temperature.
\9\ Maximum speed that the system controls would operate the compressor in normal operation in 5 [deg]F ambient temperature.


[[Page 64598]]

* * * * *

3.6.6 Heating Mode Tests for Northern Heat Pumps With Triple-Capacity 
Compressors

* * * * *

                                   Table 15--Heating Mode Test Conditions for Units With a Triple-Capacity Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                     Air entering indoor unit ([deg]F)    Air entering outdoor unit ([deg]F)
         Test description         ----------------------------------------------------------------------------  Compressor capacity   Heating air volume
                                      Dry bulb           Wet bulb           Dry bulb           Wet bulb                                      rate
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 Test (required, steady)......              70  60 (max)............              62  56.5................  Low.................  Heating Minimum.\1\
H12 (required, steady)...........              70  60 (max)............              47  43..................  High................  Heating Full-
                                                                                                                                      Load.\2\
H1C2 Test (optional,\8\ cyclic...              70  60 (max)............              47  43..................  High................  (\3\)
H11 Test (required, steady)......              70  60 (max)............              47  43..................  Low.................  Heating Minimum.\1\
H1C1 Test (optional, cyclic).....              70  60 (max)............              47  43..................  Low.................  (\4\)
H23 Test (optional, steady)......              70  60 (max)............              35  33..................  Booster.............  Heating Full-
                                                                                                                                      Load.\2\
H22 Test (required)..............              70  60 (max)............              35  33..................  High................  Heating Full-
                                                                                                                                      Load.\2\
H21 Test (required...............              70  60 (max)............              35  33..................  Low.................  Heating Minimum.\1\
H33 Test (required, steady)......              70  60 (max)............              17  15..................  Booster.............  Heating Full-
                                                                                                                                      Load.\2\
H3C3 Test 5 6 (optional, cyclic).              70  60 (max)............              17  15..................  Booster.............  (\7\)
H32 Test (required, steady)......              70  60 (max)............              17  15..................  High................  Heating Full-
                                                                                                                                      Load.\2\
H31 Test \5\ (required, steady)..              70  60 (max)............              17  15..................  Low.................  Heating Minimum.\1\
H43 Test (required, steady)......              70  60 (max)............               5  4 (max).............  Booster.............  Heating Full-
                                                                                                                                      Load.\2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5 of this appendix.
\2\ Defined in section 3.1.4.4 of this appendix.
\3\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
  during the H12 test.
\4\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
  during the H11 test.
\5\ Required only if the heat pump's performance when operating at low compressor capacity and outdoor temperatures less than 37 [deg]F is needed to
  complete the HSPF2 calculations in section 4.2.6 of this appendix.
\6\ If note #5 to this table applies, the equations for Qk=1h(35) and Ek=1h (17) in section 3.6.6 of this appendix may be used in lieu of conducting the
  H21 test.
\7\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
  during the H33 test.
\8\ Required only if the heat pump locks out low-capacity operation at lower outdoor temperatures

* * * * *

3.7 Test Procedures for Steady-State Maximum Temperature and High 
Temperature Heating Mode Tests (the H01, H1, H12, 
H11, and H1N tests)

* * * * *
    c. For mobile home and space-constrained ducted coil-only system 
tests,
    (1) For two-stage or variable-speed systems, for all steady-
state maximum temperature and high temperature tests (i.e., the 
H01, H11, H12, and H1N 
tests), increase Qck(T) by the quantity calculated in Equation 3.7-1 
to this appendix and increase Eick(T) by the quantity calculated in 
Equation 3.7-2 to this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.041

[GRAPHIC] [TIFF OMITTED] TR25OC22.042

Where:

DFPCMHSC is the default fan power coefficient (watts) for 
mobile-home and space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.043

And %FLAVR is the air volume rate used for the test, expressed as a 
percentage of the cooling full load air volume rate. For all tests 
specifying the full-load air volume rate (e.g., the H12 
and H1N tests), set %FLAVR to 100%. For tests that 
specify the heating minimum air volume rate or heating intermediate 
air volume rate (i.e., the H01 and H11 tests) 
and for which the specified minimum or intermediate air volume rate 
is greater than or equal to 75 percent of the cooling full-load air 
volume rate and less than the cooling full-load air volume rate, set 
%FLAVR to the ratio of the specified air volume rate and the cooling 
full-load air volume rate, expressed as a percentage.

    (2) For single-stage systems, for all steady-state maximum 
temperature and high temperature tests (i.e., the H1 test), increase 
Qck(T) by the quantity calculated in Equation 3.7-3 to this appendix 
and increase Eck(T) by the quantity calculated in Equation 3.7-4 to 
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.044


[[Page 64599]]


[GRAPHIC] [TIFF OMITTED] TR25OC22.045

Where VS is the average measured indoor air volume rate expressed in 
units of cubic feet per minute of standard air (scfm).

    d. For non-mobile, non-space-constrained home ducted coil-only 
system tests,
    (1) For two-stage or variable-speed systems, for all steady-
state maximum temperature and high temperature tests (i.e., the 
H01, H11, H12, and H1N 
tests), increase Qck(T) by the quantity calculated in Equation 3.7-5 
to this appendix and increase Eck(T) by the quantity calculated in 
Equation 3.7-6 to this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.046

[GRAPHIC] [TIFF OMITTED] TR25OC22.047

Where:

    DFPCC is the default fan power coefficient (watts) 
for non-mobile-home and non-space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.048

And %FLAVR is the air volume rate used for the test, expressed as a 
percentage of the cooling full load air volume rate. For all tests 
specifying the full-load air volume rate (e.g., the H12 
and H1N tests), set %FLAVR to 100%. For tests that 
specify the heating minimum air volume rate or heating intermediate 
air volume rate (i.e., the H01 and H11 tests) 
and for which the specified minimum or intermediate air volume rate 
is greater than or equal to 75 percent of the cooling full-load air 
volume rate and less than the cooling full-load air volume rate, set 
%FLAVR to the ratio of the specified air volume rate and the cooling 
full-load air volume rate, expressed as a percentage.

    (2) For single-stage systems, for all steady-state maximum 
temperature and high temperature tests (i.e., the H1 test), increase 
Qck(T) by the quantity calculated in Equation 3.7-7 to this appendix 
and increase Eck(T) by the quantity calculated in Equation 3.7-8 to 
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.049

[GRAPHIC] [TIFF OMITTED] TR25OC22.050

Where VS is the average measured indoor air volume rate 
expressed in units of cubic feet per minute of standard air (scfm).
* * * * *

3.8 Test Procedures for the Cyclic Heating Mode Tests (the 
H0C1, H1C, H1C1 and H1C2 Tests).

* * * * *
    b. For ducted coil-only system heat pumps (excluding the special 
case where a variable-speed fan is temporarily removed),
    (1) For mobile home and space-constrained ducted coil-only 
systems,
    (i) For two-stage or variable-speed systems, for all cyclic 
heating tests (i.e., the H1C1 and H1C2 tests), 
increase qcyc by the amount calculated using Equation 
3.5-2 to this appendix. Additionally, increase ecyc by 
the amount calculated using Equation 3.5-3 to this appendix.
    (ii) For single-stage systems, for all cyclic heating tests 
(i.e., the H1C and H1C1 tests), increase qcyc 
by the amount calculated using Equation 3.5-4 to this appendix. 
Additionally, increase ecyc by the amount calculated 
using Equation 3.5-5 to this appendix.
    (2) For non-mobile home and non-space-constrained ducted coil-
only systems,
    (i) For two-stage or variable-speed systems, for all cyclic 
heating tests (i.e., the H1C1 and H1C2 tests), 
increase qcyc by the amount calculated using Equation 
3.5-6 to this appendix. Additionally, increase ecyc by 
the amount calculated using Equation 3.5-7 to this appendix.
    (ii) For single-stage systems, for all cyclic heating tests 
(i.e., the H1C and H1C1 tests), increase qcyc 
by the amount calculated using Equation 3.5-8 to this appendix. 
Additionally, increase ecyc by the amount calculated 
using Equation 3.5-9 to this appendix.
    In making these calculations, use the average indoor air volume 
rate (Vs) determined from the section 3.7 of this appendix steady-
state heating mode test conducted at the same test conditions.
* * * * *

3.9.1 Average Space Heating Capacity and Electrical Power Calculations

* * * * *

[[Page 64600]]

[GRAPHIC] [TIFF OMITTED] TR25OC22.051

    (1) For mobile home and space-constrained ducted coil-only 
system tests,
    (i) For two-stage or variable-speed systems, for all frost 
accumulation tests (i.e., the H21, H22, and 
H2V tests), increase Qhk(35) by the quantity 
calculated in Equation 3.9.1-1 to this appendix and increase Ehk 
(35) by the quantity calculated in Equation 3.9.1-2 to this 
appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.052

[GRAPHIC] [TIFF OMITTED] TR25OC22.053

Where:

DFPCMHSC is the default fan power coefficient (watts) for 
mobile-home and space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.054

And %FLAVR is the air volume rate used for the test, expressed as a 
percentage of the cooling full load air volume rate. For all tests 
specifying the full-load air volume rate (e.g., the H22 
test), set %FLAVR to 100%. For tests that specify the heating 
minimum air volume rate or heating intermediate air volume rate 
(i.e., the H21 and H2v tests) and for which 
the specified minimum or intermediate air volume rate is greater 
than or equal to 75 percent of the cooling full-load air volume rate 
and less than the cooling full-load air volume rate, set %FLAVR to 
the ratio of the specified air volume rate and the cooling full-load 
air volume rate, expressed as a percentage.

    (ii) For single-stage systems, for all frost accumulation tests 
(i.e., the H2 test), increase Qhk(35) by the quantity calculated in 
Equation 3.9.1-3 to this appendix and increase Qhk(35) by the 
quantity calculated in Equation 3.9.1-4 to this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.055

[GRAPHIC] [TIFF OMITTED] TR25OC22.056

Where Vs is the average measured indoor air volume rate expressed in 
units of cubic feet per minute of standard air (scfm).

    (2) For non-mobile home and non-space-constrained ducted coil-
only systems,
    (i) For two-stage or variable-speed systems, for all frost 
accumulation tests (i.e., the H21, H22, and 
H2V tests), increase Qhk(35) by the quantity calculated 
in Equation 3.9.1-5 to this appendix and increase Ehk(35) by the 
quantity calculated in Equation 3.9.1-6 to this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.057

[GRAPHIC] [TIFF OMITTED] TR25OC22.058

Where:

DFPCC is the default fan power coefficient (watts) for 
non-mobile-home and non-space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.059

And %FLAVR is the air volume rate used for the test, expressed as a 
percentage of the cooling full load air volume rate. For all tests 
specifying the full-load air volume rate (e.g., the H22 
test), set %FLAVR to 100%. For tests that specify the heating 
minimum air volume rate or heating intermediate air volume rate 
(i.e., the H21 and H2v tests) and for which 
the specified minimum or intermediate air volume rate is greater 
than or equal to 75 percent of the cooling full-load air volume rate 
and less than the cooling full-load air volume rate, set %FLAVR to 
the ratio of the specified air volume rate and the cooling full-load 
air volume rate, expressed as a percentage.

    (ii) For single-stage systems, for all frost accumulation tests 
(i.e., the H2 test), increase Qhk (35) by the quantity calculated in 
Equation 3.9.1-7 to this appendix and increase Ehk (35) 
by the quantity calculated in Equation 3.9.1-8 to this appendix.

[[Page 64601]]

[GRAPHIC] [TIFF OMITTED] TR25OC22.060

[GRAPHIC] [TIFF OMITTED] TR25OC22.061

Where Vs is the average measured indoor air volume rate expressed in 
units of cubic feet per minute of standard air (scfm).
* * * * *

4.1.4 SEER2 Calculations for an Air Conditioner or Heat Pump Having a 
Variable-Speed Compressor

    Calculate SEER2 using Equation 4.1-1 to this appendix. Evaluate 
the space cooling capacity, Qc\k=1\(Tj), and 
electrical power consumption, Ec\k=1\(Tj), of 
the test unit when operating at minimum compressor speed and outdoor 
temperature Tj.. Use:
[GRAPHIC] [TIFF OMITTED] TR25OC22.062

[GRAPHIC] [TIFF OMITTED] TR25OC22.063

     Where Qc\k=1\(82) and [Edot]c\k=1\(82) 
are determined from the B1 test, Qc\k=1\(67) 
and Ec\k=1\(67) are determined from the F1 
test, and all four quantities are calculated as specified in section 
3.3 of this appendix. Evaluate the space cooling capacity, 
Qc\k=2\(Tj), and electrical power consumption, 
[Edot]c\k=2\(Tj), of the test unit when 
operating at full compressor speed and outdoor temperature 
Tj. Use Equations 4.1.3-3 and 4.1.3-4 to this appendix, 
respectively, where Qc\k=2\(95) and 
[Edot]ck=2(95) are determined from the A2 
test, Qc\k=2\(82) and [Edot]c\k=2\(82) are 
determined from the B2 test, and all four quantities are 
calculated as specified in section 3.3 of this appendix. For units 
other than variable-speed non-communicating coil-only air-
conditioners or heat pumps, calculate the space cooling capacity, 
Qc\k=v\(Tj), and electrical power consumption, 
[Edot]c\k=v\(Tj), of the test unit when 
operating at outdoor temperature Tj and the intermediate 
compressor speed used during the section 3.2.4 (and Table 8) 
EV test of this appendix using:
[GRAPHIC] [TIFF OMITTED] TR25OC22.064

[GRAPHIC] [TIFF OMITTED] TR25OC22.065

Where Qc\k=v\(87) are determined from the EV 
test and calculated as specified in section 3.3 of this appendix. 
Approximate the slopes of the k=v intermediate speed cooling 
capacity and electrical power input curves, MQ and 
ME, as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC22.066

Where:
[GRAPHIC] [TIFF OMITTED] TR25OC22.067

    Use Equations 4.1.4-1 and 4.1.4-2 to this appendix, 
respectively, to calculate Qc\k=1\(87) and 
[Edot]c\k=1\(87).
* * * * *

4.1.4.2.1 Units That Are Not Variable-Speed Non-Communicating Coil-Only 
Air Conditioners or Heat Pumps

    If the unit operates at an intermediate compressor speed (k=i) 
in order to match the building cooling load at temperature 
Tj, Qc\k=1\(Tj) < BL(Tj) 
< Qc\k=2\(Tj).
[GRAPHIC] [TIFF OMITTED] TR25OC22.068


[[Page 64602]]


Where:

Qc\k=i\(Tj) = BL(Tj), the space 
cooling capacity delivered by the unit in matching the building load 
at temperature Tj, in Btu/h. The matching occurs with the 
unit operating at compressor speed k = i.
[GRAPHIC] [TIFF OMITTED] TR25OC22.069

EER\k=i\(Tj) = the steady-state energy efficiency ratio 
of the test unit when operating at a compressor speed of k = i and 
temperature Tj, Btu/h per W.

    Obtain the fractional bin hours for the cooling season, 
nj/N, from Table 19 of this section. For each temperature 
bin where the unit operates at an intermediate compressor speed, 
determine the energy efficiency ratio EER\k=i\(Tj) using 
the following equations:
    For each temperature bin where Qc\k=1\(Tj) 
< BL(Tj) < Qc\k=v\(Tj),
[GRAPHIC] [TIFF OMITTED] TR25OC22.070

    For each temperature bin where Qc\k=v\(Tj) 
< BL(Tj) < Qc\k=2\(Tj),
[GRAPHIC] [TIFF OMITTED] TR25OC22.071

Where:

EER\k=1\(Tj) is the steady-state energy efficiency ratio 
of the test unit when operating at minimum compressor speed and 
temperature Tj, in Btu/h per W, calculated using capacity 
Qc\k=1\(Tj) calculated using Equation 4.1.4-1 
to this appendix and electrical power consumption 
[Edot]c\k=1\(Tj) calculated using Equation 
4.1.4-2 to this appendix;
EER\k=v\(Tj) is the steady-state energy efficiency ratio 
of the test unit when operating at intermediate compressor speed and 
temperature Tj, in Btu/h per W, calculated using capacity 
Qc\k=v\(Tj) calculated using Equation 4.1.4-3 
to this appendix and electrical power consumption 
[Edot]c\k=v\(Tj) calculated using Equation 
4.1.4-4 to this appendix;
EER\k=2\(Tj) is the steady-state energy efficiency ratio 
of the test unit when operating at full compressor speed and 
temperature Tj, Btu/h per W, calculated using capacity 
Qc\k=2\(Tj) and electrical power consumption 
[Edot]c\k=2\(Tj), both calculated as described 
in section 4.1.4 of this appendix; and
BL(Tj) is the building cooling load at temperature 
Tj, Btu/h.

4.1.4.2.2 Variable-Speed Non-Communicating Coil-Only Air Conditioners 
or Heat Pumps

    If the unit alternates between high (k=2) and low (k=1) 
compressor capacity to satisfy the building cooling load at 
temperature Tj, Qc\k=1\(Tj) < 
BL(Tj) < Qc\k=2\(Tj).
[GRAPHIC] [TIFF OMITTED] TR25OC22.072

     Where:
    [GRAPHIC] [TIFF OMITTED] TR25OC22.073
    
the cooling mode, low capacity load factor for temperature bin j 
(dimensionless); and X\k=2\ (Tj)= 1 - X\k=1\ 
(Tj), the cooling mode, high capacity load factor for 
temperature bin j (demensionless).
Obtain the fractional bin hours for the cooling season, 
nj/N, from Table 19 to this appendix. Obtain 
Qc\k=1\(Tj), 
[Edot]c\k=1\(Tj), 
Qc\k=2\(Tj), and 
[Edot]c\k=2\(Tj) as described in section 4.1.4 
of this appendix.
* * * * *

4.2 Heating Seasonal Performance Factor 2 (HSPF2) Calculations

* * * * *
    Evaluate the building heating load using:

[[Page 64603]]

[GRAPHIC] [TIFF OMITTED] TR25OC22.074

Where:

Tj = the outdoor bin temperature, [deg]F;
Tzl = the zero-load temperature, [deg]F, which varies by 
climate region according to Table 20 to this appendix;
C = slope (adjustment) factor, which varies by climate region 
according to Table 20 to this appendix. When calculating building 
load for a variable-speed compressor system, substitute 
CVS for C;
Qc(95 [deg]F) = the cooling capacity at 95 [deg]F 
determined from the A or A2 test, Btu/h. For heating-only 
heat pump units, replace Qc(95 [deg]F) in Equation 4.2-2 
with Qh(47 [deg]F);
Qh(47 [deg]F) = the heating capacity at 47 [deg]F 
determined from the H1 test for units having a single-speed 
compressor, H12 for units having a two-capacity 
compressor, and H1N test for units having a variable-
speed compressor, Btu/h.
* * * * *

4.2.3 Additional Steps for Calculating the HSPF2 of a Heat Pump Having 
a Two-Capacity Compressor

    The calculation of the Equation 4.2-1 to this appendix 
quantities differ depending upon whether the heat pump would operate 
at low capacity (section 4.2.3.1 of this appendix), cycle between 
low and high capacity (section 4.2.3.2 of this appendix), or operate 
at high capacity (sections 4.2.3.3 and 4.2.3.4 of this appendix) in 
responding to the building load. For heat pumps that lock out low 
capacity operation at low outdoor temperatures, the outdoor 
temperature at which the unit locks out must be that specified by 
the manufacturer in the certification report so that the appropriate 
equations can be selected.
* * * * *

4.2.3.4 Heat Pump Must Operate Continuously at High (k=2) Compressor 
Capacity at Temperature Tj, BL(Tj) = 
Qh\k=2\(Tj)
[GRAPHIC] [TIFF OMITTED] TR25OC22.075

[GRAPHIC] [TIFF OMITTED] TR25OC22.076

Where:
[GRAPHIC] [TIFF OMITTED] TR25OC22.077

4.2.4 Additional Steps for Calculating the HSPF2 of a Heat Pump Having 
a Variable-Speed Compressor. Calculate HSPF2 Using Equation 4.2-1

* * * * *
    a. Minimum Compressor Speed. For units other than variable-speed 
non-communicating coil-only heat pumps, evaluate the space heating 
capacity, Qh\k=1\(Tj), and electrical power 
consumption, Eh\k=1\(Tj), of the heat pump 
when operating at minimum compressor speed and outdoor temperature 
Tj using:
[GRAPHIC] [TIFF OMITTED] TR25OC22.078

[GRAPHIC] [TIFF OMITTED] TR25OC22.079

Where Qh\k=1\(62) and Eh\k=1\(62) are 
determined from the H01 test, Qh\k=1\(47) and 
Eh\k=1\(47) are determined from the H11 test, 
and all four quantities are calculated as specified in section 3.7 
of this appendix.

    For variable-speed non-communicating coil-only heat pumps, when 
Tj is greater than or equal to 47 [deg]F, evaluate the 
space heating capacity, Qh\k=1\(Tj), and 
electrical power consumption, 
[Edot]h\k=1\(Tj), of the heat pump when 
operating at minimum compressor

[[Page 64604]]

speed as described in Equations 4.2.4-1 and 4.2.4-2 to this 
appendix, respectively. When Tj is less than 47 [deg]F, 
evaluate the space heating capacity, 
Qh\k=1\(Tj), and electrical power consumption, 
[Edot]h\k=1\(Tj) using:
[GRAPHIC] [TIFF OMITTED] TR25OC22.080

And
[GRAPHIC] [TIFF OMITTED] TR25OC22.081

Where Qh\k=1\(47) and [Edot]h\k=1\(47) are 
determined from the H11 test, and both quantities are 
calculated as specified in section 3.7 of this appendix; 
Qh\k=1\(35) and [Edot]h\k=1\(35) are 
determined from the H21 test, and are calculated as 
specified in section 3.9 of this appendix; Qh\k=1\(17) 
and [Edot]h\k=1\(17) are determined from the 
H31 test, and are calculated as specified in section 3.10 
of this appendix; and Qh\k=2\(Tj) and 
[Edot]h\k=2\(Tj) are calculated as described 
in section 4.2.4.c or 4.2.4.d of this appendix, as appropriate.

    b. Minimum Compressor Speed for Minimum-speed-limiting Variable-
speed Heat Pumps. For units other than variable-speed non-
communicating coil-only heat pumps, evaluate the space heating 
capacity, Qh\k=1\(Tj), and electrical power 
consumption, [Edot]h\k=1\(Tj), of the heat 
pump when operating at minimum compressor speed and outdoor 
temperature Tj using:
[GRAPHIC] [TIFF OMITTED] TR25OC22.082

And

[[Page 64605]]

[GRAPHIC] [TIFF OMITTED] TR25OC22.083

Where Qh\k=1\(62) and [Edot]h\k=1\(62) are 
determined from the H01 test, Qh\k=1\(47) and 
[Edot]h\k=1\(47) are determined from the H11 
test, and all four quantities are calculated as specified in section 
3.7 of this appendix; Qh\k=v\(35) and 
[Edot]h\k=v\(35) are determined from the H2v 
test and are calculated as specified in section 3.9 of this 
appendix; and Qh\k=v\(Tj) and 
[Edot]h\k=v\(Tj) are calculated using 
Equations 4.2.4-7 and 4.2.4-8 to this appendix, respectively.

    For variable-speed non-communicating coil-only heat pumps, 
evaluate the space heating capacity, 
Qh\k=1\(Tj), and electrical power consumption, 
[Edot]h\k=1\(Tj), of the heat pump as 
described in section 4.2.4.a of this appendix, using Equations 
4.2.4-1, 4.2.4-2, 4.2.4-3, and 4.2.4-4 to this appendix, as 
appropriate.
    c. Full Compressor Speed for Heat Pumps for which the 
H42 test is not conducted. Evaluate the space heating 
capacity, Qh\k=2\(Tj), and electrical power 
consumption, [Edot]h\k=2\(Tj), of the heat 
pump when operating at full compressor speed and outdoor temperature 
Tj using:
[GRAPHIC] [TIFF OMITTED] TR25OC22.084

And
[GRAPHIC] [TIFF OMITTED] TR25OC22.085

    Determine Qh\k=N\(47) and [Edot]h\k=N\(47) 
from the H1N test and the calculations specified in 
section 3.7 of this appendix. See section 3.6.4.b of this appendix 
regarding determination of the capacity Qhcalc\k=2\(47) 
and power input [Edot]hcacl\k=2\(47) used in the HSPF2 
calculations to represent the H12 Test. Determine 
Qh\k=2\(35) and [Edot]h\k=2\(35) from the 
H22 test and the calculations specified in section 3.9 of 
this appendix or, if the H22 test is not conducted, by 
conducting the calculations specified in section 3.6.4 of this 
appendix. Determine Qh\k=2\(17) and 
[Edot]h\k=2\(17) from the H32 test and the 
methods specified in section 3.10 of this appendix.
* * * * *
    e. Intermediate Compressor Speed. For units other than variable-
speed non-communicating coil-only heat pumps, calculate the space 
heating capacity, Qh\k=v\(Tj), and electrical 
power consumption, [Edot]h\k=v\(Tj), of the 
heat pump when operating at outdoor temperature Tj and 
the intermediate compressor speed used during the H2V 
test in section 3.6.4 of this appendix using:

[[Page 64606]]

[GRAPHIC] [TIFF OMITTED] TR25OC22.086

    Where Qh\k=v\(35) and [Edot]h\k=v\(35) are 
determined from the H2V test and calculated as specified 
in section 3.9 of this appendix. Approximate the slopes of the k=v 
intermediate speed heating capacity and electrical power input 
curves, MQ and ME, as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC22.087

Where:
[GRAPHIC] [TIFF OMITTED] TR25OC22.088

    Use Equations 4.2.4-1 and 4.2.4-2 to this appendix, 
respectively, to calculate Qh\k=1\(35) and 
[Edot]h\k=1\(35), whether or not the heat pump is a 
minimum-speed-limiting variable-speed heat pump.
    For variable-speed non-communicating coil-only heat pumps, there 
is no intermediate speed.

4.2.4.1 Steady-State Space Heating Capacity When Operating at Minimum 
Compressor Speed is Greater Than or Equal to the Building Heating Load 
at Temperature Tj, Qh\k=1\(Tj 
=BL(Tj).

    Evaluate the Equation 4.2-1 to this appendix quantities:
    [GRAPHIC] [TIFF OMITTED] TR25OC22.089
    
    As specified in section 4.2.3.1 of this appendix. Except now use 
Equations 4.2.4-1 and 4.2.4-2 (for heat pumps that are not minimum-
speed-limiting and are not variable-speed non-communicating coil-
only heat pumps), Equations 4.2.4-1, 4.2.4-2, 4.2.4-3, and 4.2.4-4 
as appropriate (for variable-speed non-communicating coil-only heat 
pumps), or Equations 4.2.4-5 and 4.2.4.-6 (for minimum-speed-
limiting variable-speed heat pumps that are not variable-speed non-
communicating coil-only heat pumps) to this appendix to evaluate 
Qh\k=1\(Tj) and 
[Edot]h\k=1\(Tj), respectively, and replace 
section 4.2.3.1 references to ``low capacity'' and section 3.6.3 of 
this appendix with ``minimum speed'' and section 3.6.4 of this 
appendix.

4.2.4.2 Heat Pump Operates at an Intermediate Compressor Speed (k = i) 
or, for a Variable-Speed Non-Communicating Coil-Only Heat Pump, Cycles 
Between High and Low Speeds, in Order to Match the Building Heating 
Load at a Temperature Tj, Qh\k=1\(Tj) 
< QBL(Tj) < Qh\k=2\(Tj).

    For units that are not variable-speed non-communicating coil-
only heat pumps, calculate:
[GRAPHIC] [TIFF OMITTED] TR25OC22.090

Where:
[GRAPHIC] [TIFF OMITTED] TR25OC22.091

And [delta](Tj) is evaluated using Equation 4.2.3-3, 
while:

    Qh\k=i\(Tj) = BL(Tj), the space 
heating capacity delivered by the unit in matching the building load 
at temperature (Tj), in Btu/h. The matching occurs with 
the heat pump operating at compressor speed k=i, and
    COP\k=i\(Tj) = the steady-state coefficient of 
performance of the heat pump when operating at compressor speed k=i 
and temperature Tj (dimensionless). For each temperature 
bin where the heat pump operates at an intermediate compressor 
speed, determine COP\k=i\(Tj) using the following 
equations,
    For each temperature bin where Qh\k=1\(Tj) 
< BL(Tj) < Qh\k=v\(Tj),

[[Page 64607]]

[GRAPHIC] [TIFF OMITTED] TR25OC22.092

    For each temperature bin where Qh\k=v\(Tj) 
<= BL(Tj) < Qh\k=2\(Tj),
[GRAPHIC] [TIFF OMITTED] TR25OC22.093

Where:

COPh\k=1\(Tj) is the steady-state coefficient 
of performance of the heat pump when operating at minimum compressor 
speed and temperature Tj, dimensionless, calculated using capacity 
Qh\k=1\(Tj) calculated using Equation 4.2.4-1 
or 4.2.4-3 to this appendix and electrical power consumption 
[Edot]h\k=1\(Tj) calculated using Equation 
4.2.4-2 or 4.2.4-4 to this appendix;
COPh\k=v\(Tj) is the steady-state coefficient 
of performance of the heat pump when operating at intermediate 
compressor speed and temperature Tj, dimensionless, calculated using 
capacity Qh\k=v\(Tj) calculated using Equation 
4.2.4-7 to this appendix and electrical power consumption 
[Edot]h\k=v\(Tj) calculated using Equation 
4.2.4-8 to this appendix;
COPh\k=2\(Tj) is the steady-state coefficient 
of performance of the heat pump when operating at full compressor 
speed and temperature Tj (dimensionless), calculated using capacity 
Qh\k=2\(Tj) and electrical power consumption 
[Edot]h\k=2\(Tj), both calculated as described 
in section 4.2.4 of this appendix; and
BL(Tj) is the building heating load at temperature 
Tj, in Btu/h.
[GRAPHIC] [TIFF OMITTED] TR25OC22.094

* * * * *
[FR Doc. 2022-22257 Filed 10-24-22; 8:45 am]
BILLING CODE 6450-01-P