[Federal Register Volume 86, Number 235 (Friday, December 10, 2021)]
[Proposed Rules]
[Pages 70644-70687]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-26288]



[[Page 70643]]

Vol. 86

Friday,

No. 235

December 10, 2021

Part III





Department of Energy





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





10 CFR Parts 429 and 431





Energy Conservation Program: Test Procedure for VRF Multi-Split 
Systems; Proposed Rule

  Federal Register / Vol. 86 , No. 235 / Friday, December 10, 2021 / 
Proposed Rules  

[[Page 70644]]


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

DEPARTMENT OF ENERGY

10 CFR Parts 429 and 431

[EERE-2021-BT-TP-0019]
RIN 1904-AE43


Energy Conservation Program: Test Procedure for VRF Multi-Split 
Systems

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

ACTION: Notice of proposed rulemaking and request for comment.

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

SUMMARY: The U.S. Department of Energy (``DOE'') proposes to amend the 
test procedure for variable refrigerant flow multi-split air 
conditioners and heat pumps (``VRF multi-split systems'') to 
incorporate by reference the latest version of the industry test 
standard. DOE also proposes to adopt the integrated energy efficiency 
ratio metric in its test procedures for VRF multi-split systems. 
Additionally, DOE proposes to adopt provisions in the updated industry 
test procedure relevant to certification and enforcement, including a 
controls verification procedure. DOE welcomes written comment from the 
public on any subject within the scope of this document (including 
topics not specifically raised in this proposal), as well as the 
submission of data and other relevant information.

DATES: 
    Comments: DOE will accept written comments, data, and information 
regarding this notice of proposed rulemaking (NOPR) on or before 
February 8, 2022. See section V, ``Public Participation,'' for details.
    Meeting: DOE will hold a webinar on Thursday, January 20, 2022, 
from 1:00 p.m. to 4:00 p.m. See section V, ``Public Participation,'' 
for webinar registration information, participant instructions, and 
information about the capabilities available to webinar participants.

ADDRESSES: Interested persons are encouraged to submit comments using 
the Federal eRulemaking Portal at www.regulations.gov. Follow the 
instructions for submitting comments.
    Alternatively, interested persons may submit comments, identified 
by docket number EERE-2021-BT-TP-0019, by any of the following methods:
    1. Federal eRulemaking Portal: www.regulations.gov.
    2. Email: to [email protected]. Include docket 
number EERE-2021-BT-TP-0019 in the subject line of the message. No 
telefacsimiles (``faxes'') will be accepted. For detailed instructions 
on submitting comments and additional information on this process, see 
section V of this document ``Public Participation.''
    Although DOE has routinely accepted public comment submissions 
through a variety of mechanisms, including the Federal eRulemaking 
Portal, email, postal mail or hand delivery/courier, the Department has 
found it necessary to make temporary modifications to the comment 
submission process in light of the ongoing corona virus 2019 (COVID-19) 
pandemic. DOE is currently suspending receipt of public comments via 
postal mail and hand delivery/courier. If a commenter finds that this 
change poses an undue hardship, please contact Appliance Standards 
Program staff at (202) 586-1445 to discuss the need for alternative 
arrangements. Once the COVID-19 pandemic health emergency is resolved, 
DOE anticipates resuming all of its regular options for public comment 
submission, including postal mail and hand delivery/courier.
    Docket: The docket, which includes Federal Register notices, public 
meeting/webinar attendee lists and transcripts, comments, and other 
supporting documents/materials, is available for review at 
www.regulations.gov. All documents in the docket are listed in the 
www.regulations.gov index. However, some documents listed in the index, 
such as those containing information that is exempt from public 
disclosure, may not be publicly available.
    The docket web page can be found at: www.regulations.gov/docket/EERE-2021-BT-TP-0019. The docket web page contains instructions on how 
to access all documents, including public comments, in the docket. See 
section V ``Public Participation'' for information on how to submit 
comments through www.regulations.gov.

FOR FURTHER INFORMATION CONTACT: 
    Ms. Catherine Rivest, 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) 586-7335. Email: [email protected].
    Mr. Eric Stas, U.S. Department of Energy, Office of the General 
Counsel, GC-33, 1000 Independence Avenue SW, Washington, DC 20585. 
Telephone: (202) 586-5827. Email: [email protected].
    DOE has submitted the collection of information contained in the 
proposed rule to OMB for review under the Paperwork Reduction Act, as 
amended. (44 U.S.C. 3507(d)) Comments on the information collection 
proposal shall be directed to the Office of Information and Regulatory 
Affairs, Office of Management and Budget, Attention: Sofie Miller, OIRA 
Desk Officer by email: [email protected].
    For further information on how to submit a comment, review other 
public comments and the docket, or participate in the webinar, contact 
the Appliance and Equipment Standards Program staff at (202) 287-1445 
or by email: [email protected].

SUPPLEMENTARY INFORMATION: DOE proposes to maintain and update 
previously approved incorporations by reference and incorporate by 
reference the following industry standard into parts 429 and 431:
    AHRI Standard 1230, (``AHRI 1230-2021''), ``Performance Rating of 
Variable Refrigerant Flow (VRF) Multi-Split Air-Conditioning and Heat 
Pump Equipment;'' approved 2021.
    ANSI/AHRI 1230-2010, 2010 Standard for Performance Rating of 
Variable Refrigerant Flow (VRF) Multi-Split Air-Conditioning and Heat 
Pump Equipment,'' approved August 2, 2010 and updated by addendum 1 in 
March 2011, (AHRI 1230-2010).
    Copies of AHRI 1230-2021 and AHRI 1230-2010 can be obtained from 
the Air-Conditioning, Heating, and Refrigeration Institute, 2311 Wilson 
Blvd., Suite 400, Arlington, VA 22201 (703) 524-8800, or online at: 
www.ahrinet.org/search-standards.aspx.
    DOE proposes to amend the previously approved incorporation by 
reference for the following industry standard in part 431:
    ANSI/American Society of Heating, Refrigerating and Air-
Conditioning Engineers (ASHRAE) Standard 37-2009, ``Methods of Testing 
for Rating Electrically Driven Unitary Air-Conditioning and Heat Pump 
Equipment,'' ASHRAE approved June 24, 2009.
    Copies of ANSI/ASHRAE 37-2009 can be obtained from the American 
National Standards Institute, 25 W 43rd Street, 4th Floor, New York, NY 
10036, (212) 642-4800, or online at: webstore.ansi.org/.
    See section IV.M of this document for a further discussion of these 
standards.

Table of Contents

I. Authority and Background
    A. Authority
    B. Background
II. Synopsis of the Notice of Proposed Rulemaking
III. Discussion
    A. Scope of Applicability
    B. General Comments

[[Page 70645]]

    C. Proposed Organization of the VRF Multi-Split System Test 
Procedure
    D. Industry Standards
    1. Updates to AHRI 1230
    2. ASHRAE 37
    E. Metrics
    1. IEER
    2. Test Conditions Used for Efficiency Metrics
    F. Test Method
    1. Setting Indoor Airflow and External Static Pressure
    2. Condenser Head Pressure Controls
    3. Indoor Unit Operation During Part-Load Tests
    4. Transient Testing: Oil Recovery Mode
    5. Secondary Methods for Capacity Measurement
    6. Heat Recovery
    G. Specific Components
    H. Controls Verification Procedure
    1. Background
    2. Purpose and Description
    3. Critical Parameter Definition
    4. Critical Parameter Variation and Budget Method
    5. Validation of Certified Critical Parameters
    6. Determination of Alternate Critical Parameters
    7. When the CVP Is Conducted
    I. Allowable Critical Parameter Adjustment
    1. Adjustment of Certified Critical Parameter Values
    2. Adjustment of Alternate Critical Parameter Values
    J. Certification, Compliance and Enforcement
    1. Represented Values
    2. Certification Reporting Requirements
    3. Models Required for AEDM Validation
    4. Manufacturer Involvement
    5. Certified Critical Parameter Operational Settings
    6. Enforcement Sampling Plan
    K. Test Procedure Costs
    L. Reserved Appendices for Test Procedures for Commercial Air 
Conditioning and Heating Equipment
    M. Compliance Date
IV. Procedural Issues and Regulatory Review
    A. Review Under Executive Order 12866
    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 Materials Incorporated by Reference
V. Public Participation
    A. Participation in the Webinar
    B. Procedure for Submitting Prepared General Statements for 
Distribution
    C. Conduct of the Webinar
    D. Submission of Comments
    E. Issues on Which DOE Seeks Comment
VI. Approval of the Office of the Secretary

I. Authority and Background

    Commercial package air conditioning and heating equipment is 
included in the list of ``covered equipment'' for which DOE is 
authorized to establish and amend energy conservation standards and 
test procedures. (42 U.S.C. 6311(1)(B) through (D)) Commercial package 
air conditioning and heating equipment includes variable refrigerant 
flow multi-split air conditioners and heat pumps (``VRF multi-split 
systems''). DOE's energy conservation standards and test procedure for 
VRF multi-split systems are currently prescribed at 10 CFR 431.97 and 
10 CFR 431.96, respectively. The following sections discuss DOE's 
authority to establish the test procedure for VRF multi-split systems 
and relevant background information regarding DOE's consideration of 
the test procedure for this equipment.

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 C \2\ of EPCA, Public Law 94-163 (42 U.S.C. 6311-
6317, as codified), added by Public Law 95-619, Title IV, section 
441(a), established the Energy Conservation Program for Certain 
Industrial Equipment, which sets forth a variety of provisions designed 
to improve energy efficiency. This equipment includes small, large, and 
very large commercial package air conditioning and heating equipment, 
which includes VRF multi-split systems, the subject of this NOPR. (42 
U.S.C. 6311(1)(B)-(D))
---------------------------------------------------------------------------

    \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 C was redesignated Part A-1.
---------------------------------------------------------------------------

    The energy conservation program under EPCA consists essentially of 
four parts: (1) Testing, (2) labeling, (3) Federal energy conservation 
standards, and (4) certification and enforcement procedures. Relevant 
provisions of EPCA include definitions (42 U.S.C. 6311), energy 
conservation standards (42 U.S.C. 6313), test procedures (42 U.S.C. 
6314), labeling provisions (42 U.S.C. 6315), and the authority to 
require information and reports from manufacturers (42 U.S.C. 6316).
    The Federal testing requirements consist of test procedures that 
manufacturers of covered equipment must use as the basis for: (1) 
Certifying to DOE that their equipment complies with the applicable 
energy conservation standards adopted pursuant to EPCA (42 U.S.C. 
6316(b); 42 U.S.C. 6296), and (2) making representations about the 
efficiency of that equipment (42 U.S.C. 6314(d)). Similarly, DOE uses 
these test procedures to determine whether the equipment complies with 
relevant standards promulgated under EPCA.
    Federal energy efficiency requirements for covered equipment 
established under EPCA generally supersede State laws and regulations 
concerning energy conservation testing, labeling, and standards. (42 
U.S.C 6316(a) and (b); 42 U.S.C 6297) DOE may, however, grant waivers 
of Federal preemption for particular state laws or regulations, in 
accordance with the procedures and other provisions of EPCA. (42 U.S.C. 
6316(b)(2)(D))
    Under 42 U.S.C. 6314, EPCA sets forth the criteria and procedures 
DOE must follow when prescribing or amending test procedures for 
covered equipment. EPCA requires that any test procedures prescribed or 
amended under this section must be reasonably designed to produce test 
results which reflect energy efficiency, energy use or estimated annual 
operating cost of a given type of covered equipment during a 
representative average use cycle and requires that test procedures not 
be unduly burdensome to conduct. (42 U.S.C 6314(a)(2))
    With respect to VRF multi-split systems, EPCA requires that the 
test procedures shall be those generally accepted industry testing 
procedures or rating procedures developed or recognized by the Air-
Conditioning, Heating, and Refrigeration Institute (``AHRI'') or the 
American Society of Heating, Refrigerating, and Air-Conditioning 
Engineers (``ASHRAE''), as referenced in ASHRAE/IES Standard 90.1, 
``Energy Standard for Buildings Except Low-Rise Residential Buildings'' 
(``ASHRAE Standard 90.1''). (42 U.S.C 6314(a)(4)(A)) Further, if such 
an industry test procedure is amended, DOE must amend its test 
procedure to be consistent with the amended industry test procedure 
unless it determines, by a rule published in the Federal Register and 
supported by clear and convincing evidence, that the amended test 
procedure would be unduly burdensome to conduct or would not produce 
test results that reflect the energy efficiency, energy use, and 
estimated operating costs of that equipment during a representative 
average use cycle. (42 U.S.C. 6314(a)(4)(B))

[[Page 70646]]

    EPCA also requires that, at least once every 7 years, DOE evaluate 
test procedures for each type of covered equipment, including VRF 
multi-split systems, to determine whether amended test procedures would 
more accurately or fully comply with the requirements for the test 
procedures to not be unduly burdensome to conduct and be reasonably 
designed to produce test results that reflect energy efficiency, energy 
use, and estimated operating costs during a representative average use 
cycle. (42 U.S.C 6314(a)(1))
    In addition, if the Secretary determines that a test procedure 
amendment is warranted, the Secretary must publish proposed test 
procedures in the Federal Register, and afford interested persons an 
opportunity (of not less than 45 days duration) to present oral and 
written data, views, and arguments on the proposed test procedures. (42 
U.S.C 6314(b)) If DOE determines that test procedure revisions are not 
appropriate, DOE must publish in the Federal Register its determination 
not to amend the test procedures. (42 U.S.C. 6314(a)(1)(A)(ii))
    DOE is proposing amendments to the test procedures for VRF multi-
split systems in satisfaction of its statutory obligations under EPCA.

B. Background

    DOE's existing test procedure for VRF multi-split systems appears 
at 10 CFR 431.96 (``Uniform test method for the measurement of energy 
efficiency of commercial air conditioners and heat pumps''). The 
Federal test procedure for VRF multi-split systems was last amended in 
a final rule for standards and test procedures for certain commercial 
heating, air conditioning, and water heating equipment published on May 
16, 2012 (``May 2012 Final Rule''). 77 FR 28928. With regard to VRF 
multi-split systems, the May 2012 Final Rule adopted the test procedure 
American National Standards Institute (``ANSI'')/AHRI Standard 1230-
2010 ``2010 Standard for Performance Rating of Variable Refrigerant 
Flow (VRF) Multi-Split Air-Conditioning and Heat Pump Equipment,'' 
approved August 2, 2010 and updated by Addendum 1 in March 2011 
(``ANSI/AHRI 1230-2010''). 77 FR 28928, 28945-28946; see 10 CFR 431.96, 
Table 1. Specifically, the DOE test procedure for VRF multi-split 
systems was modified to reference ANSI/AHRI 1230-2010 with Addendum 1, 
but omitting sections 5.1.2 and 6.6. 77 FR 28928, 28990-28991. The May 
2012 Final Rule also adopted additional requirements, listed in 10 CFR 
431.96(c)-(f), for measuring the energy efficiency ratio (``EER'') and 
coefficient of performance (``COP'') for air-cooled VRF multi-split 
systems with a cooling capacity between 65,000 Btu/h and 760,000 Btu/h 
and water-source VRF multi-split systems with a cooling capacity less 
than 760,000 Btu/h. Id. These additional requirements specify 
provisions for equipment set-up and provide for limited involvement of 
manufacturer representatives during testing. 77 FR 28928, 28991.
    In 2016,\3\ ASHRAE Standard 90.1 was updated, but the 2016 update 
did not make changes to the test procedure references in ASHRAE 
Standard 90.1-2013 for VRF multi-split systems. On July 25, 2017, DOE 
published a request for information (``RFI'') (``July 2017 ASHRAE TP 
RFI'') to collect information and data to consider amendments to DOE's 
test procedures for commercial package air conditioning and heating 
equipment with the test procedure updates included in ASHRAE Standard 
90.1-2016. 82 FR 34427. As part of the July 2017 ASHRAE TP RFI DOE 
requested comment on the VRF multi-split systems test procedure, under 
the 7-year lookback requirement. 82 FR 34427, 34429. DOE identified 
several issues that might have warranted modifications to the 
applicable VRF multi-split systems test procedure, in particular 
concerning incorporation by reference of the most recent version of the 
relevant industry standard(s); efficiency metrics and calculations; and 
clarification of test methods. 82 FR 34427, 34427.
---------------------------------------------------------------------------

    \3\ No publication date is printed on ASHRAE Standard 90.1-2016, 
but ASHRAE issued a press release on October 26, 2016, which is 
available at www.ashrae.org/news/2016/ashrae-ies-publish-2016-energy-efficiency-standard. Last accessed April 30, 2021.
---------------------------------------------------------------------------

    DOE received a number of comments regarding VRF multi-split systems 
from interested parties in response to the July 2017 ASHRAE TP RFI, 
which covered multiple categories of equipment. Table I-1 lists the 
commenters that provided comments relevant to VRF multi-split systems, 
along with each commenter's abbreviated name used throughout this NOPR. 
Discussion of the relevant comments, and DOE's responses, are provided 
in the appropriate sections of this document.

   Table I-1--Interested Parties Providing Comment on VRF Multi-Split
           Systems in Response to the July 2017 ASHRAE TP RFI
------------------------------------------------------------------------
                Name                      Abbreviation          Type
------------------------------------------------------------------------
Air-Conditioning, Heating, and       AHRI.................  IR.
 Refrigeration Institute.
Appliance Standards Awareness        Joint Advocates......  EA.
 Project, Alliance to Save Energy,
 American Council for an Energy-
 Efficient Economy, Northwest
 Energy Efficiency Alliance, and
 Northwest Power and Conservation
 Council.
Carrier Corporation, part of United  Carrier..............  M.
 Technologies Climate, Controls &
 Security Business.
Goodman Global, Inc................  Goodman..............  M.
Trane Technologies.................  Trane................  M.
Lennox International Inc...........  Lennox...............  M.
Mitsubishi Electric Cooling &        Mitsubishi...........  M.
 Heating, a division of Mitsubishi
 Electric US, Inc.
National Comfort Institute.........  NCI..................  IR.
Pacific Gas and Electric Company,    CA IOUs..............  U.
 Southern California Gas Company,
 San Diego Gas and Electric, and
 Southern California Edison
 (collectively, California Investor-
 Owned Utilities).
------------------------------------------------------------------------
EA: Efficiency/Environmental Advocate; IR: Industry Representative; M:
  Manufacturer; U: Utility.


[[Page 70647]]

    A parenthetical reference at the end of a comment quotation or 
paraphrase provides the location of the item in the public record.\4\
    In September 2017, AHRI published an update to ANSI/AHRI 1230, 
i.e., ANSI/AHRI 1230-2014 with Addendum 1 (although published in 2017, 
the update uses a 2014 designation).
    On April 11, 2018, DOE published in the Federal Register a notice 
of its intent to establish a negotiated rulemaking working group 
(``Working Group'') under the Appliance Standards and Rulemaking 
Federal Advisory Committee (``ASRAC''), in accordance with the Federal 
Advisory Committee Act \5\ and the Negotiated Rulemaking Act,\6\ to 
negotiate the proposed test procedure and amended energy conservation 
standards for VRF multi-split systems. 83 FR 15514. The purpose of the 
Working Group was to discuss and, if possible, reach consensus on a 
proposed rule regarding the test procedure and energy conservation 
standards for VRF multi-split systems, as authorized by EPCA. Id. at 83 
FR 15514.
---------------------------------------------------------------------------

    \4\ The parenthetical reference provides a reference for 
information located in a docket related to DOE's rulemaking to 
develop test procedure for VRF multi-split systems. As noted, the 
July 2017 ASHRAE TP RFI addressed multiple different equipment 
categories and is available under docket number EERE-2017-BT-TP-
0018. As this NOPR addresses only VRF multi-split systems, it has 
been assigned a separate docket number i.e., EERE-2021-BT-TP-0019). 
The references are arranged as follows: (Commenter name, comment 
docket ID number, page of that document).
    \5\ 5 U.S.C. App. 2, Public Law 92-463.
    \6\ 5 U.S.C. 561-570, Public Law 104-320.
---------------------------------------------------------------------------

    The Working Group comprised 21 voting members including 
manufacturers, energy efficiency advocates, utilities, and trade 
organizations.\7\ On October 1, 2019, the Working Group reached 
consensus on a term sheet (``VRF TP Term Sheet'') that includes the 
following recommendations, which highlight the most substantial 
changes: (Docket No. EERE-2018-BT-STD-0003-0044)
---------------------------------------------------------------------------

    \7\ A complete list of the ASRAC VRF Working Group members is 
available at: www.energy.gov/eere/buildings/appliance-standards-and-rulemaking-federal-advisory-committee#Variable%20Refrigerant%20Flow%20Multi-Split%20Air%20Conditioners%20and%20Heat%20Pumps%20Working%20Group.

    1. VRF multi-split systems should be rated with the Integrated 
Energy Efficiency Ratio (``IEER'') metric to allow consumers to make 
consistent comparisons with rooftop air conditioner ratings.
    2. The amended test procedure should not be required until the 
compliance date of amended energy conservation standards.
    3. The Federal test procedure for VRF multi-split systems should 
be consistent with the September 20, 2019 draft version of AHRI 
1230, with additional amendments to be implemented after the 
conclusion of ASRAC negotiations.

(Id at pp. 1, 3)
    The additional recommended amendments are discussed further in 
section III of this NOPR.
    On May 18, 2021, AHRI published an updated industry standard for 
VRF multi-split systems AHRI Standard 1230, ``2021 Standard for 
Performance Rating of Variable Refrigerant Flow (VRF) Multi-Split Air-
Conditioning and Heat Pump Equipment'' (``AHRI Standard 1230-2021''), 
which in turn references ANSI/ASHRAE Standard 37-2009 (including Errata 
Sheet issued October 3, 2016) ``Methods of Testing for Rating 
Electrically Driven Unitary Air-Conditioning and Heat Pump Equipment'' 
(``ANSI/ASHRAE 37-2009'') for additional test setup and methodology 
specifications. AHRI standard 1230-2021 is discussed in further detail 
in section III.D.1 of this NOPR.

II. Synopsis of the Notice of Proposed Rulemaking

    In this NOPR, DOE proposes to update Sec.  431.96, ``Uniform test 
method for the measurement of energy efficiency of commercial air 
conditioners and heat pumps,'' to align the relevant references to the 
most recent version of the industry test procedure as follows: (1) 
Incorporate by reference AHRI 1230-2021 and ANSI/ASHRAE 37-2009 
(including Errata Sheet issued October 3, 2016); and (2) establish 
provisions for determining IEER for VRF multi-split systems. DOE 
further proposes to add new appendices D and D1 to subpart F of part 
431, both entitled ``Uniform test method for measuring the energy 
consumption of variable refrigerant flow multi-split air conditioners 
and heat pumps (other than air-cooled with rated cooling capacity less 
than 65,000 Btu/h),'' (``appendix D'' and ``appendix D1'', 
respectively). The current DOE test procedure for VRF multi-split 
systems would be relocated to appendix D without change, and the new 
test procedure adopting AHRI 1230-2021 would be established in appendix 
D1 for determining IEER. Compliance with appendix D1 would not be 
required until such time as compliance is required with amended energy 
conservation standards for VRF multi-split systems that rely on IEER, 
should DOE adopt such standards.
    In this NOPR, DOE also proposes to update its certification, 
compliance, and enforcement (``CCE'') provisions for VRF multi-split 
systems, to provide information that is necessary for testing VRF 
multi-split systems consistent with the updated industry test procedure 
AHRI 1230-2021. Most significantly, these proposed changes include the 
incorporation of the controls verification procedure (``CVP'') from 
AHRI 1230-2021 into DOE's product-specific enforcement provisions at 10 
CFR 429.134, as well as accompanying certification requirements at 10 
CFR 429.43. DOE is also proposing to amend the sampling size 
requirements for enforcement from a maximum sample size of not more 
than four units to require testing of two units.
    DOE's proposed actions are summarized in Table II-1 and addressed 
in detail in section III of this document.

  Table II-1--Summary of Changes in Proposed Test Procedure Relative to
                         Current Test Procedure
------------------------------------------------------------------------
                                     Proposed test
  Current DOE test procedure           procedure           Attribution
------------------------------------------------------------------------
Incorporates by reference ANSI/ Incorporates by         Updates to the
 AHRI 1230-2010.                 reference in a new      applicable
                                 Appendix D1 AHRI 1230-  industry test
                                 2021 and ANSI/ASHRAE    procedures.
                                 37-2009 (including
                                 Errata Sheet issued
                                 October 3, 2016).
Includes provisions for         Includes provisions     Updates to the
 determining EER.                for determining both    applicable
                                 EER and IEER.           industry test
                                                         procedures.
Does not include VRF-specific   Includes provisions in  Establish VRF-
 provisions for determination    10 CFR 429.43           specific
 of represented values in 10     specific to VRF multi-  provision for
 CFR 429.43.                     split systems to        determination
                                 determine represented   of represented
                                 values for units        values.
                                 approved for use with
                                 multiple
                                 refrigerants, and
                                 determine represented
                                 values for different
                                 indoor unit
                                 combinations.

[[Page 70648]]

 
Includes certification          Adopts reporting        Establish
 requirements in 10 CFR 429.43   requirements            reporting
 consistent with testing to      consistent with new     requirements
 EER per AHRI 1230-2010.         test requirements of    consistent with
                                 AHRI 1230-2021,         updated
                                 including tested        industry test
                                 combination,            method.
                                 certified critical
                                 parameter values, and
                                 instructions for
                                 conducting the
                                 controls verification
                                 procedure (``CVP'').
Does not include VRF-specific   Adopts product-         Establish
 enforcement provisions in 10    specific enforcement    provisions for
 CFR 429.134.                    provisions for VRF      DOE testing of
                                 multi-split systems     VRF multi-split
                                 including:              systems.
                                 Verification of
                                 cooling capacity,
                                 configuration of unit
                                 under test,
                                 manufacturer
                                 involvement in
                                 assessment or
                                 enforcement testing,
                                 provisions for when
                                 DOE would conduct a
                                 CVP, and how CVP
                                 results would affect
                                 critical parameters
                                 used in IEER
                                 enforcement testing
                                 by DOE.
Does not provide VRF-specific   Specifies VRF-specific  Establish AEDM
 instruction for validating      AEDM validation         instructions
 alternative methods for         criteria that are       specific to VRF
 determining energy efficiency   dependent on indoor     multi-split
 and energy use (``AEDM'') at    unit combinations       systems.
 10 CFR 429.70.                  offered by the
                                 manufacturer.
Requires selection of not more  Specifies an            Establish VRF-
 than 4 samples for DOE          enforcement testing     specific
 enforcement testing following   sample size of 2        provision for
 the sampling plan in 10 CFR     units, with             enforcement
 429.110.                        compliance based on     sampling plan.
                                 the arithmetic mean
                                 of the sample.
------------------------------------------------------------------------

    DOE has tentatively determined that the proposed amendments 
described in section III of this NOPR regarding the establishment of 
appendix D would not alter the measured efficiency of VRF multi-split 
systems, or require retesting solely as a result of DOE's adoption of 
the proposed amendments to the test procedure, if made final. DOE has 
tentatively determined that the proposed amendments regarding the test 
procedure in proposed appendix D1 would alter measured efficiency if 
made final and that such amendments are consistent with the updated 
industry test procedure. Further, use of the updated industry test 
procedure provisions as proposed and the proposed amendments to 
representation requirements in 10 CFR 429.43 and 10 CFR 429.70 would 
not be required until the compliance date of amended standards in terms 
of IEER. Additionally, DOE has tentatively determined that the proposed 
amendments, if made final, would not increase the cost of testing 
relative to the updated industry test procedure. Discussion of DOE's 
proposed actions are addressed in detail in section III of this NOPR.

III. Discussion

    DOE's test procedure for VRF multi-split systems is set forth at 
Sec.  431.96. DOE's current regulations require that manufacturers test 
VRF multi-split systems using ANSI/AHRI 1230-2010 with Addendum 1, 
except for Sections 5.1.2 and 6.6. See Table 1 at 10 CFR 431.96. DOE's 
current test procedure also requires that manufacturers adhere to 
certain additional requirements listed in 10 CFR 431.96(c) through (f), 
which specify additional provisions for equipment set-up and provide 
for limited involvement of manufacturer representatives during testing.
    In the following sections, DOE discusses in detail relevant test 
procedure issues and proposes changes to the current DOE test procedure 
for VRF multi-split systems. DOE is generally proposing amendments such 
that the Federal test procedure is consistent with AHRI 1230-2021 and 
changes to the current certification, compliance and enforcement 
(``CCE'') regulations for VRF multi-split systems, also consistent with 
the updated industry test standard.

A. Scope of Applicability

    This rulemaking applies to variable refrigerant flow multi-split 
air conditioners and heat pumps. DOE defines variable refrigerant flow 
multi-split air conditioners and heat pumps as units of commercial 
package air conditioning and heating equipment that are configured as a 
split system air conditioner or heat pump incorporating a single 
refrigerant circuit, with one or more outdoor units, at least one 
variable-speed compressor or an alternate compressor combination for 
varying the capacity of the system by three or more steps, and multiple 
indoor fan coil units, each of which is individually metered and 
individually controlled by an integral control device and common 
communications network and which can operate independently in response 
to multiple indoor thermostats. 10 CFR 431.92. Variable refrigerant 
flow implies three or more steps of capacity control on common, inter-
connecting piping. 10 CFR 431.92. VRF multi-split heat pumps use 
reverse cycle refrigeration as its primary heating source and may 
include second supplemental heating by means of electrical resistance, 
steam, hot water, or gas. Id.
    DOE is not proposing to amend the current scope of the Federal test 
procedure for VRF multi-split systems. DOE's test procedure regulations 
for commercial air conditioners and heat pumps at 10 CFR 431.96 include 
test procedures that apply to air-cooled VRF multi-split air 
conditioners, air-cooled VRF multi-split heat pumps, and water-source 
VRF multi-split heat pumps,\8\ all with cooling capacity less than 
760,000 Btu/h. Table 1 of 10 CFR 431.96. Single-phase, air-cooled VRF 
multi-split air conditioners and heat pumps with cooling capacity less 
than 65,000 Btu/h are subject to DOE's consumer product regulations for 
central air conditioners, and test procedures for these products are 
specified in appendices M and M1 to subpart B of 10 CFR part 430. Test 
procedures for three-phase, air-cooled VRF multi-split systems with 
cooling capacity less than 65,000 Btu/h are not addressed in this NOPR 
and will instead be addressed in a separate test procedure rulemaking 
for air-cooled, three-phase, small commercial package air conditioning 
and heating equipment with a cooling capacity of less than 65,000 Btu/
h.
---------------------------------------------------------------------------

    \8\ The EPCA definition for ``commercial package air 
conditioning and heating equipment'' specifically excludes ground 
water source equipment. (42 U.S.C. 6311(8)(A)).
---------------------------------------------------------------------------

B. General Comments

    In response to the July 2017 ASHRAE TP RFI, DOE received several 
general

[[Page 70649]]

comments not specific to any one equipment category or test procedure. 
This section addresses those comments.
    NCI recommended that DOE follow the development of ASHRAE 221P, 
``Test Method to Measure and Score the Operating Performance of an 
Installed Constant Volume Unitary HVAC System,'' and consider where it 
may be appropriately applied within EPCA test procedures. (NCI, No. 4 
at pp. 1-2) NCI stated that it has collected data indicating that 
typical split systems and packaged units serving residential and small 
commercial buildings typically deliver 50 percent to 60 percent of the 
rated capacity to the occupied zone, thereby making laboratory tests 
unrepresentative of field performance. Id.
    DOE notes that ASHRAE Standard 90.1 does not reference ANSI/ASHRAE 
Standard 221-2020, ``Test Method to Field-Measure and Score the Cooling 
and Heating Performance of an Installed Unitary HVAC System'' \9\ as 
the applicable test procedure for VRF multi-split systems. NCI also did 
not provide data on field performance or any correlations between field 
performance and laboratory test performance for VRF multi-split systems 
for DOE to consider. Furthermore, ASHRAE 221-2020 does not provide a 
method to determine the efficiency of VRF multi-split systems. As 
discussed, DOE is proposing to incorporate by reference AHRI 1230-2021, 
the most recently published version of the industry test procedure 
recognized by ASHRAE Standard 90.1 for VRF multi-split systems.
---------------------------------------------------------------------------

    \9\ Available at https://webstore.ansi.org/Standards/ASHRAE/ANSIASHRAEStandard2212020.
---------------------------------------------------------------------------

    The CA IOUs commented that while the July 2017 ASHRAE TP RFI 
expressed interest in reducing burden to manufacturers, DOE already 
took steps to reduce this burden by allowing alternative energy 
efficiency or energy use determination methods (``AEDMs''). (CA IOUs, 
No. 7 at pp. 1-2). The CA IOUs stated that there are no further 
opportunities to streamline test procedures to limit testing burden. 
Id. at 2. Additionally, the CA IOUs emphasized the importance of 
accurate efficiency ratings for its incentive programs and customer 
knowledge, referencing the statutory provision that test procedures 
must produce results that are representative of the product's energy 
efficiency. Id.
    Lennox stated that it generally supports DOE meeting the statutory 
requirements to design test procedures to measure energy efficiency 
during an average use cycle, but requested that DOE also consider 
overall impacts to consumers and manufacturers. (Lennox, No. 8 at pp. 
1-2) Lennox also stated that, in commercial applications, predicting 
actual energy use from a single metric is difficult, and such a metric 
better serves as a point of comparison. Id. Lennox suggested that DOE 
strike a balance between evaluating equipment in a meaningful way 
without introducing unwarranted regulatory burden from overly complex 
test procedures or calculations that provide little value to consumers. 
Id.
    In response to the CA IOUs and Lennox, DOE notes that its approach 
to test procedures is governed by EPCA's requirements. As discussed, 
EPCA prescribes that the test procedures for commercial package air 
conditioning and heating equipment must be those generally accepted 
industry testing procedures or rating procedures developed or 
recognized by industry as referenced in ASHRAE Standard 90.1. (42 
U.S.C. 6314(a)(4)(A)) If such an industry test procedure is amended, 
DOE must update its test procedure to be consistent with the amended 
industry test procedure, unless DOE determines by a rule published in 
the Federal Register and supported by clear and convincing evidence 
that the amended test procedure would not meet the requirements in 42 
U.S.C. 6314(a)(2) and (3) related to representative use and test 
burden. (42 U.S.C. 6314(a)(4)(B) and (C)) In establishing or amending 
its test procedures, DOE must develop test procedures that are 
reasonably designed to produce test results which reflect energy 
efficiency, energy use, and estimated operating costs of a type of 
industrial equipment during a representative average use cycle and that 
are not unduly burdensome to conduct. (42 U.S.C 6314(a)(2)) DOE's 
considerations of these requirements in relation to individual test 
method issues are discussed within the relevant sections of this NOPR.
    The Joint Advocates stated that there a number of ambiguities in 
industry test procedures and that DOE should address these ambiguities 
in order to provide a level playing field for manufacturers and to 
ensure that any verification or enforcement testing is consistent with 
the manufacturer's own testing. (Joint Advocates, No. 9 at p. 2)
    DOE has evaluated the industry test standard in the context of the 
statutory criteria regarding representativeness of the measured energy 
efficiency and test burden. To the extent there are provisions in the 
relevant industry test procedure that may benefit from further detail, 
such provisions are discussed in the previous sections of this 
document.

C. Proposed Organization of the VRF Multi-Split System Test Procedure

    DOE is proposing to relocate and centralize the current test 
procedure for VRF multi-split systems to a new appendix D to subpart F 
of part 431. As proposed, appendix D would not amend the current test 
procedure. The test procedure as provided in proposed appendix D would 
continue to reference ANSI/AHRI 1230-2010 with Addendum 1 and provide 
for determining EER and COP. The proposed appendix D would centralize 
the additional test provisions currently applicable under 10 CFR 
431.96, i.e., optional break-in period for tests conducted using AHRI 
1230-2010 (10 CFR 431.96(c)); refrigerant line length corrections for 
tests conducted using AHRI 1230-2010 (10 CFR 431.96(d); additional 
provisions for equipment set-up (10 CFR 431.96(e); and manufacturer 
involvement in assessment or enforcement testing for variable 
refrigerant flow systems (10 CFR 431.96(f)). As proposed, VRF multi-
split systems would be required to be tested according to appendix D 
until such time as compliance is required with an amended energy 
conservation standard that relies on the IEER metric, should DOE adopt 
such a standard.
    Pursuant to EPCA, DOE is also proposing to amend the test procedure 
for VRF multi-split systems by adopting AHRI 1230-2021 in a new 
appendix D1 to subpart F of part 431. DOE proposes to adopt the updated 
version of AHRI 1230, including the IEER metric, as discussed in the 
following sections. As proposed, VRF multi-split systems would not be 
required to test according to the test procedure in proposed appendix 
D1 until such time as compliance is required with an amended energy 
conservation standard that relies on the IEER metric, should DOE adopt 
such a standard.

D. Industry Standards

1. Updates to AHRI 1230
    As discussed, DOE's current test procedure for VRF multi-split 
systems incorporates by reference ANSI/AHRI 1230-2010, excluding 
Sections 5.1.2 and 6.6. See Table 1 at 10 CFR 431.96. In September 
2017, AHRI published an updated version of AHRI Standard 1230--AHRI 
Standard 1230-2014 with Addendum 1 ``2014 Standard for Performance 
Rating of Variable Refrigerant Flow (VRF) Multi-Split Air-Conditioning 
and Heat Pump Equipment'' (AHRI 1230-2014 with Addendum 1). Based on a 
comparison of the 2014 version and ANSI/AHRI 1230-2010, the edits 
changed the scope of the VRF certification program and

[[Page 70650]]

VRF-specific definitions, and added appendices for unit configuration 
for capacity above 65,000 Btu/h and development of supplemental testing 
instructions. DOE tentatively concludes that the changes in the 2014 
version do not substantively affect testing for EER (the current 
Federal metric). Therefore, DOE has tentatively determined that its 
current test procedure, which references ANSI/AHRI 1230-2010, is 
consistent with AHRI 1230-2014 with Addendum 1.
    As discussed in section I.B, the VRF TP Term Sheet recommended that 
DOE adopt the 2019 draft version of AHRI 1230, but with several 
additional changes to be implemented, including:
     A hierarchy of instructions for how to set up the unit 
under test, and a clarification that ``as-shipped'' settings should be 
used as a last resort when instructions are not provided in the 
supplemental testing instructions (``STI'') and/or the manufacturer's 
installation instructions (``MII'').
     Equations and example calculations of adjustments to 
measured results for steady-state tests if sensible heat ratio 
(``SHR'') \10\ limits are not met at the 100 percent full load and/or 
75 percent part load cooling test points.
---------------------------------------------------------------------------

    \10\ Cooling load is composed of both sensible and latent 
portions. The sensible load is the energy required to reduce the 
temperature of the incoming air, without any phase change. The 
latent load is the energy required to change the moisture in the air 
from water vapor into a liquid phase as it condenses on the cooling 
coil. Sensible heat ratio is a ratio of the sensible cooling 
capacity to the total cooling capacity at a given test condition.
---------------------------------------------------------------------------

     Further definition of the draft CVP, including definition 
of time periods for determining critical parameter validation and 
allowable critical parameter tolerances using manufacturer-provided 
data. (Docket No. EERE-2018-BT-STD-0003-0044 at p. 2)
    After the VRF ASRAC Working Group meetings in 2019, DOE provided 
technical support in an AHRI 1230 Technical Committee to address the 
outstanding items identified in the VRF TP Term Sheet. On the last 
item--determining critical parameter tolerances--DOE compiled 
anonymized, aggregated test data to share with the committee. In a 
presentation to the AHRI 1230 Technical Committee on September 10, 
2020, DOE shared data on the variability of critical parameter results 
as measured during different CVP runs, as well as data on how the 
measured IEER changed in response to changes in critical parameters. 
(EERE-2018-BT-STD-0003-0063) DOE presented options that could be 
considered to express the maximum allowable variation in critical 
parameters as a ``budget'' (see section III.H.4 of this NOPR for 
description of the critical parameter budget method). The AHRI 1230 
Technical Committee incorporated a budget of 70 points (a measure of 
critical parameter variation, as discussed in section III.H.4 of this 
NOPR) in AHRI 1230.
    Following the completion of the AHRI 1230 Technical Committee 
meetings, in May 2021, AHRI published AHRI 1230-2021, which supersedes 
AHRI 1230-2014 with Addendum 1. The 2019 draft considered by the 
Working Group incorporated preliminary versions of the CVP, provided 
example calculations for IEER, and added other new provisions to 
clarify how the test procedure should be conducted. The changes 
recommended in the VRF TP Term Sheet were incorporated into AHRI 1230-
2021. The following list includes substantive changes in AHRI 1230-2021 
as compared to AHRI 1230-2010 currently used for certification:
    1. Air-cooled VRF multi-split systems with cooling capacity less 
than 65,000 Btu/h were removed from the scope of the industry test 
standard. These systems are addressed by AHRI 210/240-2023 
``Performance Rating of Unitary Air-conditioning & Air-source Heat Pump 
Equipment.''
    2. Maximum SHR limits of 0.82 and 0.85 were added for full load and 
75 percent part-load conditions, respectively.
    3. A CVP was added that verifies that the values certified in the 
STI for setting critical parameters during steady-state testing are 
within the range of critical parameters that would be used by the 
system's native controls at the same conditions. A 70-point budget was 
also added as the criteria for critical parameter validation during the 
CVP.
    4. A hierarchy was added indicating which sources of manufacturer's 
instructions to use during testing in the case of conflicting 
information among different sources.
    5. Provisions were updated for refrigerant piping length 
requirements and for the correction factors applied in the case of 
excess refrigerant piping length used during testing.
    6. For water-source equipment, the maximum water flow rate was 
reduced and part-load entering water temperatures were modified.
    7. New provisions were added to specify test methods and conditions 
for cases in which condenser head pressure controls result in unstable 
operation in part-load cooling tests.
    8. The provisions for tested combinations, which specify the indoor 
unit combination to be used for testing, were updated to remove 
``highest sales volume'' requirements and replaced with a specific 
hierarchy based on ``indoor unit model family''--e.g., wall-mounted, 
compact 4-way ceiling cassette, mid-static ducted.
    9. A maximum airflow rate of 55 standard cubic feet per minute 
(``scfm'') per 1000 Btu/h was added for non-ducted indoor units, and 
the maximum airflow rate was increased for ducted indoor units from 
37.5 scfm per 1000 Btu/h to 42 scfm per 1000 Btu/h.
    10. Test tolerances for indoor air entering wet-bulb temperatures 
were increased. Specifically, the indoor wet-bulb temperature operating 
tolerance was increased from 1 [deg]F to 1.8 [deg]F. The indoor wet-
bulb temperature condition tolerance was also increased from 0.30 
[deg]F to 0.36 [deg]F. Additionally, the operating tolerance for 
external static pressure (``ESP'') for ducted units was changed from 
0.05 in H2O to 10 percent of the ESP reading.
    11. Appendix D to ANSI/AHRI 1230-2010 with Addendum 1, ``Test 
Requirements,'' was amended in ANSI/AHRI 1230-2021 and redesignated as 
Appendix E, ``ANSI/ASHRAE Standard 37-2009 Clarifications/Exceptions.'' 
This appendix provides additional instruction and exceptions to the use 
of ANSI/ASHRAE 37-2009.
    12. Informative appendices were added that show example 
calculations for IEER and the CVP ``budget'' method, which calculates 
the variation between measured critical parameter values and STI-
reported critical parameter values.\11\
---------------------------------------------------------------------------

    \11\ See section III.H.4 of this NOPR for further discussion of 
the CVP budget method.
---------------------------------------------------------------------------

    DOE is proposing to adopt the updated version of AHRI 1230, 
including the IEER metric, as described further in section III.E of 
this NOPR. DOE proposes to incorporate by reference AHRI 1230-2021 in a 
new appendix D1 to subpart F of part 431, which would become required 
for use starting on the compliance date for any amended energy 
conservation standards based on IEER. DOE reviewed AHRI 1230-2021 to 
determine whether it meets the requirements of EPCA for incorporation 
by reference as part of the Federal test method for determining 
compliance with minimum energy conservation standards. DOE has 
tentatively determined that the changes in AHRI 1230-2021 better 
reflect the field performance of VRF multi-split systems and provide 
additional clarification for testing provisions. Specifically, in the 
proposed test procedure for VRF multi-split systems in the proposed 
appendix D1, DOE is proposing to reference the following

[[Page 70651]]

sections from AHRI 1230-2021: Section 3 (except 3.10), Section 5 
(except 5.1.2), Section 6 (except 6.3.3 and 6.5), Section 11, and 
Section 12. DOE is also proposing to reference appendix E from AHRI 
1230-2021 but is not proposing to reference the other appendices. DOE 
proposes to exclude the remaining sections from its test procedure for 
VRF multi-split systems because they are either (1) informative 
appendices not needed in the DOE test procedure, (2) procedures 
specific to the AHRI verification program that are not warranted for a 
DOE test procedure, or (3) sections for which DOE is proposing 
modifications as discussed in the following sections of this NOPR, and 
listed as excepted previously.
2. ASHRAE 37
    ANSI/ASHRAE 37-2009, which provides a method of test for many 
categories of air conditioning and heating equipment, is referenced for 
testing VRF multi-split systems by ANSI/AHRI 1230-2010, ANSI/AHRI 1230-
2014 with Addendum 1, and AHRI 1230-2021. In particular, appendix E of 
AHRI 1230-2021 provides additional instruction and exceptions regarding 
the application of the test methods specified in ANSI/ASHRAE 37-2009 to 
VRF multi-split systems. As stated, ANSI/ASHRAE 37-2009 is referenced 
in ANSI/AHRI 1230-2010, which is currently the referenced industry test 
standard in the DOE test procedure for VRF multi-split systems. To 
reflect the use of ANSI/ASHRAE 37-2009 in conducting testing according 
to AHRI 1230-2021, DOE is proposing to incorporate by reference ANSI/
ASHRAE 37-2009 in its test procedure for VRF multi-split systems. 
Specifically, in the proposed appendix D1, DOE is proposing to 
reference all sections of ANSI/ASHRAE 37-2009 except Sections 1, 2, and 
4. Specific issues discussed in the July 2017 ASHRAE TP RFI pertaining 
to ANSI/ASHRAE 37-2009, and the related comments, are addressed in 
section III.F of this NOPR.
    On October 3, 2016, ASHRAE published an errata sheet for ANSI/
ASHRAE 37-2009 that corrected the total heating capacity equations for 
the outdoor liquid coil method in section 7.6.5.1 of the test 
standard.\12\ Therefore, DOE proposes to incorporate by reference ANSI/
ASHRAE 37-2009 including the Errata sheet published on October 3, 2016 
in the proposed appendix D1.
---------------------------------------------------------------------------

    \12\ www.ashrae.org/standards-research--technology/standards-errata.
---------------------------------------------------------------------------

E. Metrics

1. IEER
    DOE currently prescribes energy conservation standards for air-
cooled VRF multi-split systems with cooling capacity greater than or 
equal to 65,000 Btu/h and water-source VRF multi-split heat pumps in 
terms of the EER metric for cooling-mode operation and in terms of the 
COP metric for heating-mode operation. Both EER and COP capture the 
system performance at single, full-load operating points in cooling and 
heating mode (i.e., single outdoor air temperatures for air-cooled 
systems and single entering water temperatures for water-source 
systems). Neither metric provides a seasonal or load-weighted measure 
of energy efficiency.
    In contrast, the IEER metric factors in the efficiency of operating 
at full-load conditions as well as part-load conditions of 75-percent, 
50-percent, and 25-percent of full-load capacity. In general, the IEER 
metric provides a more representative measure of field performance by 
weighting the full-load and part-load efficiencies by the average 
amount of time equipment spends operating at each load. The IEER metric 
was first introduced into ASHRAE 90.1 for commercial air-cooled, water-
cooled, and evaporatively-cooled air conditioning and heat pump 
equipment in the 2008 Supplement to Standard 90.1-2007, effective 
January 1, 2010. ASHRAE Standard 90.1-2010 included minimum efficiency 
levels in terms of both EER and IEER for air-cooled VRF multi-split 
systems. ASHRAE Standard 90.1-2016 added IEER levels for water-source 
VRF multi-split heat pump systems, including systems with cooling 
capacity less than 65,000 Btu/h, in addition to the specified EER 
levels.
    On January 15, 2016, DOE published a direct final rule for energy 
conservation standards for air-cooled commercial unitary air 
conditioners (air-cooled CUACs, or ACUACs), which amended the energy 
conservation standards for ACUACs and changed the cooling efficiency 
metric from EER to IEER, with compliance required starting January 1, 
2018. 81 FR 2420. VRF multi-split systems provide space heating and 
cooling to commercial buildings in a similar range of climatic 
conditions as ACUACs. In this NOPR, DOE has initially determined that 
IEER represents the efficiency of VRF multi-split systems operating in 
the field more accurately than EER because cooling loads do not require 
operation at full-load for the vast majority of cooling hours.
    As discussed in the July 2017 ASHRAE TP RFI, manufacturers already 
test and rate VRF multi-split systems using the IEER metric in the AHRI 
Directory of Certified Product Performance for VRF multi-split 
systems.\13\ 82 FR 34427, 34445. The publication of IEER ratings for 
most units on the market and the inclusion of minimum efficiency levels 
and test procedures in terms of IEER for VRF multi-split systems in 
ASHRAE Standard 90.1 and AHRI Standard 1230 indicates that IEER is an 
industry-accepted and widely-used metric for measuring efficiency of 
VRF multi-split systems. In the July 2017 ASHRAE TP RFI, DOE requested 
comment on any issues it should consider regarding potentially using 
IEER as an efficiency metric for air-cooled VRF multi-split systems 
with a cooling capacity greater than or equal to 65,000 Btu/h and 
water-source VRF multi-split systems. 82 FR 34427, 34445-34446.
---------------------------------------------------------------------------

    \13\ The AHRI directory for VRF multi-split systems is available 
at: www.ahridirectory.org/NewSearch?programId=72&searchTypeId=3.
---------------------------------------------------------------------------

    In response to the July 2017 ASHRAE TP RFI, AHRI, Lennox, 
Mitsubishi, Trane, Goodman, Carrier, the CA IOUs, and the Joint 
Advocates all supported using an IEER metric for VRF multi-split 
systems. (AHRI, No. 11 at p. 31; Lennox, No. 8 at p. 6; Mitsubishi, No. 
10 at p. 1; Trane, No. 12 at p. 2; Goodman, No. 14 at p. 5; Carrier, 
No. 6 at p. 17; CA IOUs, No. 7 at p. 4; Joint Advocates, No. 9 at p. 6) 
AHRI, Goodman, and Carrier further commented that IEER should replace 
EER as the Federal metric, and not be used as an additional metric. 
(AHRI, No. 11 at p. 31; Goodman, No. 14 at p. 5; Carrier, No. 6 at p. 
17) AHRI and Goodman asserted that EPCA requires DOE to establish a 
single performance standard or a single design requirement. (AHRI, No. 
11 at p. 31; Goodman, No. 14 at p. 5) The Joint Advocates commented 
that VRF multi-split systems should be regulated based on both EER and 
IEER, while the CA IOUs commented that the IEER metric is appropriate 
as a national standard as long as the EER value at each of the test 
points is individually published. (Joint Advocates, No. 9 at p. 6; CA 
IOUs, No. 7 at p. 4) The Joint Advocates further commented that 
regulating based on both EER and IEER would have no impact on test 
burden because manufacturers are already rating their equipment for 
both. (Joint Advocates, No. 9 at p. 6) CA IOUs also commented that the 
highest ambient test point required by DOE's test procedure (95 [deg]F 
outdoor air dry-bulb temperature) is not representative of VRF multi-
split systems operating conditions in the hot and dry western climate, 
and

[[Page 70652]]

recommended adding a hot-dry condition test point in IEER. (CA IOUs, 
No. 7 at p. 4)
    During the proceedings of the ASRAC negotiated rulemaking process, 
the Working Group discussed the appropriateness of rating VRF equipment 
using an IEER metric at the test points prescribed in ANSI/AHRI 1230-
2010. (Docket No. EERE-2018-BT-STD-0003-0051 at pp. 13-14) The Working 
Group also discussed the potential for adding new test points to the 
IEER metric, including the proposal to add a hot-dry condition test 
point for IEER, which was also suggested by the CA IOUs in their 
response to the 2017 ASHRAE TP RFI. (EERE-2018-BT-STD-0003-0051; CA 
IOUs, No. 7 at p. 4) Ultimately, the Working Group did not adopt a hot-
dry condition test point in its recommendations. The VRF TP Term Sheet 
states that VRF multi-split systems should be rated with the IEER 
metric to allow consumers to make consistent comparisons with other 
products using the IEER metric. (Docket No. EERE-2018-BT-STD-0003-0044 
at p. 1) Additionally, during a presentation delivered by DOE at the 
September 20, 2019 Working Group meeting, AHRI indicated that they 
would submit a letter to the docket stating that the AHRI certification 
program would continue to use both EER and IEER cooling metrics for VRF 
multi-split systems. (Docket No. EERE-2018-BT-STD-0003-0052 at p. 72).
    In this NOPR, DOE is proposing to adopt the relevant provisions in 
AHRI 1230-2021 to determine IEER for VRF multi-split systems. As noted, 
the energy conservation standards for VRF multi-split systems are in 
terms of EER. Testing according to the DOE test procedure to determine 
EER would continue to be required until such time as the energy 
conservation standards are amended to rely on IEER, should DOE adopt 
such changes to the standards. Requiring both EER and IEER would result 
in multiple standards applicable to the cooling function of a VRF 
multi-split systems. However, EPCA directs DOE to establish an amended 
uniform national standard for the relevant ASHRAE equipment at the 
minimum level specified in the amended ASHRAE/IES Standard 90.1. (42 
U.S.C. 6313(a)(6)(A)(ii)(I)) EPCA's use of ``uniform national 
standard'' and ``minimum level'' appears to prohibit DOE from 
establishing more than one standard applicable to the cooling function 
of a VRF multi-split system. Id.
    Based on the discussion in the preceding paragraphs, DOE initially 
finds, that pursuant to 42 U.S.C. 6314(a)(4)(B)), there is a lack of 
clear and convincing evidence to establish a test procedure for IEER 
other than as specified in AHRI 1230-2021.
    Consistent with DOE's proposal to adopt IEER in its test procedure 
for VRF multi-split systems, DOE also proposes to amend the current 
definition for ``Integrated Energy Efficiency Ratio, or IEER'' at Sec.  
431.92 to differentiate between ACUACs and VRF multi-split systems. 
Both systems would use the IEER efficiency metric, but the applicable 
test procedures are in separate sections of the CFR. Specifically, DOE 
proposes to amend the definition of ``Integrated Energy Efficiency 
Ratio, or IEER'' at 10 CFR 431.92 to clarify that IEER is measured per 
the test procedure in appendix A to subpart F of part 431 for ACUACs 
and per the proposed test procedure at appendix D1 for VRF multi-split 
systems.
    Issue 1: DOE requests feedback on its proposal to adopt IEER as 
determined under AHRI 1230-2021 in the Federal test procedure for VRF 
multi-split systems. DOE also seeks comment on its proposed amendment 
to the definition for IEER at Sec.  431.92 to distinguish between the 
test procedures for ACUACs and VRF multi-split systems.
    DOE notes that AHRI 1230-2021 also provides test methods and 
calculations for measuring simultaneous cooling and heating efficiency 
(``SCHE''). ASHRAE Standard 90.1-2019 does not include efficiency 
levels for VRF multi-split systems in terms of SCHE, and the VRF TP 
Working Group did not consider or analyze the SCHE metric (and thus it 
was not included in the VRF TP Term Sheet). Further, SCHE is a 
distinctly different metric from other efficiency metrics for VRF 
multi-split systems, as SCHE combines cooling and heating performance 
into a single metric. For these reasons DOE is not proposing to include 
SCHE in its updated test procedure for VRF multi-split systems.
2. Test Conditions Used for Efficiency Metrics
    AHRI 1230-2021 provides a number of test conditions for a variety 
of tests referred to in the industry test procedure as ``standard 
rating tests'' and ``performance operating tests.'' DOE is proposing to 
specify in the test procedure for VRF multi-split systems which test 
conditions would be required for compliance with standards, were DOE to 
amend the energy conservation standards based on AHRI 1230-2021, and to 
specify additional test conditions that would be included in the DOE 
test procedure for making optional representations of efficiency.
a. Air-Cooled VRF Multi-Split Systems
    Table 9 of AHRI 1230-2021 specifies test conditions for standard 
rating and performance operating tests for air-cooled VRF multi-split 
systems. Were DOE to amend the applicable energy conservation standards 
based on AHRI 1230-2021, the relevant ratings for cooling tests would 
be those referred to as ``standard rating conditions'' in AHRI 1230-
2021. To clarify this, DOE proposes to specify in section 3.1 of the 
proposed appendix D1 that the cooling test conditions used for 
compliance would be the ``Standard Rating Conditions, Cooling'' and 
``Standard Rating Part-Load Conditions (IEER)'' conditions specified in 
Table 9 of AHRI 1230-2021.
    For heating mode tests of air-cooled VRF multi-split systems, AHRI 
1230-2021 includes ``Standard Rating Conditions'' for both a ``High 
Temperature Steady-state Test for Heating'' and a ``Low Temperature 
Steady-state Test for Heating'' (conducted at 47 [deg]F and 17 [deg]F 
outdoor air dry-bulb temperatures, respectively). Were DOE to amend the 
applicable energy conservation standards based on AHRI 1230-2021, the 
relevant ratings would be those referred to as ``High Temperature 
Steady-state Test for Heating'' in AHRI 1230-2021 and measured at 47 
[deg]F. To clarify this, DOE proposes to specify in section 4.1 of 
appendix D1 that the heating test conditions used for compliance would 
be the ``Standard Rating Conditions (High Temperature Steady-state Test 
for Heating)'' conditions specified in Table 9 of AHRI 1230-2021. 
Additionally, DOE proposes to also include the low-temperature (17 
[deg]F) heating test condition specified in Table 9 of AHRI 1230-2021 
(referred to as ``Low Temperature Steady-state Test for Heating'') in 
the proposed test procedure, and specify in section 4.1.1 of appendix 
D1 that representations of COP at this low-temperature heating 
condition are optional.
b. Water-Source VRF Multi-Split Systems
    Tables 10 and 11 of AHRI 1230-2021 specify test conditions for 
cooling mode and heating mode tests, respectively, for water-source VRF 
multi-split systems. These tables include conditions for both standard 
rating and performance operating tests. Furthermore, both tables 
specify test conditions for three different applications of water-
source VRF multi-split systems: Water loop heat pumps, ground-water 
heat pumps, and ground-loop heat pumps. Were DOE to amend the energy 
conservation

[[Page 70653]]

standards based on AHRI 1230-2021, the relevant ratings for cooling and 
heating tests would be those referred to as ``standard rating 
conditions'' for ``water loop heat pumps'' in AHRI 1230-2021. To 
clarify this, DOE proposes to specify in section 3.2 of the proposed 
appendix D1 that the test conditions used for compliance would be the 
``Part-load Conditions (IEER)'' conditions specified for ``Water Loop 
Heat Pumps'' in Table 10 of AHRI 1230-2021 for cooling mode tests and 
the ``Standard Rating Test'' conditions specified for ``Water Loop Heat 
Pumps'' in Table 11 of AHRI 1230-2021 for heat pump heating mode tests.
    DOE also proposes to include cooling and heating mode test 
conditions specified for ``Ground-loop Heat Pumps'' in Tables 10 and 11 
in the DOE test procedure for optional representations for water-source 
VRF multi-split systems. Specifically, DOE proposes to specify in 
section 4.2.1 of appendix D1 that representations of EER made using the 
``Standard Rating Test'' conditions specified for ``Ground-loop Heat 
pumps'' in Table 10 of AHRI 1230-2021 and representations of COP made 
using the ``Standard Rating Test'' conditions specified for ``Ground-
loop Heat Pumps'' in Table 11 of AHRI 1230-2021 are optional.
    The EPCA definition for ``commercial package air conditioning and 
heating equipment'' specifically excludes ground-water-source equipment 
(42 U.S.C. 6311(8)(A)). Therefore, DOE is not proposing to include test 
conditions in the proposed Federal test procedure for making optional 
representations of cooling and heating efficiency for water-source VRF 
multi-split systems in the ``Ground-water Heat Pump'' application.

F. Test Method

    This section discusses certain issues related to testing VRF multi-
split systems, several of which were identified by DOE in the July 2017 
ASHRAE TP RFI and subsequently addressed in AHRI 1230-2021. 
Additionally, several of the issues raised by DOE in the July 2017 
ASHRAE TP RFI and by commenters relate to changes to the 2019 draft 
version of AHRI 1230 recommended by the VRF TP Term Sheet. These VRF TP 
Term Sheet recommendations have also been addressed in AHRI 1230-2021. 
Therefore comments received regarding these issues are briefly 
summarized but are otherwise addressed by referencing the relevant 
language in AHRI 1230-2021.
1. Setting Indoor Airflow and External Static Pressure
    The performance of a VRF multi-split system can be significantly 
affected by variation in ESP or operation with an indoor airflow that 
is different from the intended or designed airflow. In the July 2017 
ASHRAE TP RFI, DOE raised several issues associated with setting indoor 
airflow and ESP for VRF multi-split systems. 82 FR 34427, 34446. These 
issues are addressed in Section 6.3.1 of AHRI 1230-2021, and DOE is not 
proposing any deviations from those provisions. These issues are 
discussed in the following sections.
a. Indoor Airflow and ESP Settings for Different Capacity Ranges
    DOE noted in the July 2017 ASHRAE TP RFI that a 2015 draft version 
of AHRI 1230 contained one set of instructions for setting the indoor 
air flow rates for systems with capacities less than 65,000 Btu/h 
(section 6.3.3.1) and another set for systems with capacities larger 
than 65,000 Btu/h (section 6.4.1). 82 FR 34427, 34446. It was not clear 
to DOE why alternate approaches are required for different systems, 
because the indoor units generally do not differ by system capacity. 
Id. Therefore, DOE requested comment on whether there should be a 
consistent approach for setting indoor airflow and ESP across all 
capacity ranges of VRF multi-split systems. Id. In response, Lennox 
commented that the airflow and ESP requirements for VRF multi-split 
systems with cooling capacity above and below 65,000 Btu/h should be 
the same. (Lennox, No. 8 at p. 8). Carrier commented that the different 
approach for setting indoor airflow rates across capacity ranges was 
being addressed by AHRI in drafting AHRI 1230. (Carrier, No. 6 at p. 
19) AHRI commented that a more recent draft of AHRI 1230 contained new 
requirements for airflow, and that the test requirements would be 
different for part-load conditions but consistent for full-load 
conditions. (AHRI, No. 11 at pp. 34-35).
    AHRI 1230-2021 includes updated provisions in Section 6.3.1 for 
setting indoor airflow and ESP that apply to air-cooled VRF multi-split 
systems with cooling capacity greater than or equal to 65,000 Btu/h and 
to all water-cooled VRF multi-split systems. Air-cooled VRF multi-split 
systems with rated cooling capacity less than 65,000 Btu/h are not 
within the scope of AHRI 1230-2021, and are instead within the scope of 
a different industry test procedure (AHRI 210/240-2023). Therefore, 
test procedures for three-phase, air-cooled VRF multi-split systems 
with cooling capacity less than 65,000 Btu/h are not being considered 
in this NOPR. Those will be addressed in a separate test procedure 
rulemaking for air-cooled, three-phase, small commercial package air 
conditioning and heating equipment with a cooling capacity of less than 
65,000 Btu/h. DOE is not proposing any deviations from Section 6.3.1 of 
AHRI 1230-2021 regarding setting indoor airflow and ESP.
b. Test Setup for Non-Ducted Indoor Units
    DOE explained in the July 2017 ASHRAE TP RFI that if a common duct 
is used for the combined discharge airflow of multiple individual 
units, the airflow for each individual unit cannot be verified. 82 FR 
34427, 34447. Even if the ESP is set to zero in an attempt to replicate 
operation without ducting, based on a measurement of downstream 
pressure in a discharge duct this does not always guarantee that flow 
is identical to free discharge conditions, due to sensitivity of such 
in-duct pressure measurements to the air movement in the duct. Id. 
Finally, specification of unusually high air flows for testing of free 
discharge in indoor units may boost measured performance inconsistent 
with field operation. Id. DOE requested comment on how to confirm 
airflow for each indoor unit individually, or when there is deviation 
from free-discharge operation, when there is a common duct for multiple 
individual units. Id.
    In response, AHRI, Carrier, Mitsubishi, and Goodman commented that 
it is not feasible nor economically justified to confirm airflow of 
individual indoor units when a common duct is used. (AHRI, No. 11 at p. 
35; Carrier, No. 6 at p. 20; Mitsubishi, No. 10 at p. 2; Goodman, No. 
14 at p. 7) Specifically, AHRI stated that it is currently infeasible 
to confirm airflow for multiple individual indoor units.\14\ (AHRI, No. 
11 at p. 35) AHRI stated that the third-party laboratory that it uses 
for its certification program is only equipped with one code tester 
(i.e., airflow-measuring apparatus) per test room. (Id.) AHRI 
suggested, however, that the use of thermocouple grids on every outlet 
on each unit and temperature checks on indoor liquid and indoor gas per 
unit, combined with static pressure taps, helps identify any potential 
deviation from free-discharge

[[Page 70654]]

operation on any unit. (Id.) Lennox commented that the test protocol 
for testing non-ducted indoor units does not guarantee zero static 
pressure at the inlet and outlet of each indoor unit; however, solving 
this issue is not easy due to laboratory limitations. (Lennox, No. 8 at 
p. 8) Lennox suggested that improvement to the test method could be 
made to measure airflow at each indoor unit, but that would require 
larger and more test rooms. (Id.) Lennox noted that experience has 
indicated that the common duct may show a lower airflow measurement 
compared to measuring airflow of each non-ducted indoor unit 
independently. (Id. at pp. 8-9)
---------------------------------------------------------------------------

    \14\ AHRI stated that it is currently not feasible to test VRF 
products with up to 12 indoor units. Given DOE's awareness that 
industry has the capability to test VRF multi-split systems with up 
to 12 indoor units, DOE interprets AHRI's comment as referring to 
the infeasibility of confirming the airflow of individual indoor 
units.
---------------------------------------------------------------------------

    Section 6.3.1.3 of AHRI 1230-2021 allows the use of a common duct 
to connect multiple indoor units to a single airflow-measuring 
apparatus. To ensure that the tests for non-ducted indoor units are 
being conducted under conditions that reflect operation absent the use 
of a common duct, AHRI 1230-2021 specifies that a static pressure tap 
be placed in the center of each face of each discharge chamber that 
connects each indoor unit to the common duct, and that the static 
pressure difference between each discharge chamber measurement and 
intake opening of the equipment under test be zero. DOE tentatively 
surmises that the approach provided in AHRI 1230-2021 represents 
industry consensus regarding the most appropriate and representative 
configuration for testing non-ducted indoor units. As discussed, DOE is 
not proposing any deviations from the provisions in Section 6.3.1 of 
AHRI 1230-2021 regarding setting indoor airflow and ESP.
c. Maximum Airflow Rate
    Increasing the airflow rates at which indoor units of VRF multi-
split systems are tested generally improves measured performance. 
Testing at an unusually high airflow rate may boost performance in a 
manner inconsistent with field operation. As part of the July 2017 
ASHRAE TP RFI, DOE requested comment on whether there should be an 
upper limit of airflow per capacity for all non-ducted VRF indoor 
units, such as 55 scfm per 1,000 Btu/h, which was the limit included in 
the 2015 draft version of AHRI 1230. 82 FR 34427, 34447.
    In response, AHRI, Carrier, and Goodman all expressed support for 
an airflow limit of 55 scfm per 1,000 Btu/h for non-ducted units, 
stating that such an upper limit would prevent manufacturers from 
running higher airflows for rating purposes that are not typical for 
actual use. (AHRI, No. 11 at pp. 34-35; Carrier, No. 6 at p. 20; 
Goodman, No. 14 at p. 7) Lennox did not support the 55 scfm per 1,000 
Btu/h airflow limit for non-ducted indoor units, and commented that to 
align the test procedure with field operation, VRF multi-split systems 
should be tested without an airflow limit. (Lennox, No. 8 at p. 9)
    Section 6.3.1.3 of AHRI 1230-2021 includes an upper limit on 
airflow per capacity for VRF multi-split systems with non-ducted indoor 
units during cooling tests. The rated airflow for each non-ducted 
indoor unit must not exceed the lower of two limits: (1) 105% of the 
nominal airflow published in product literature for that indoor unit, 
or (2) 55 scfm per 1,000 Btu/h of nominal indoor unit cooling capacity. 
Section 6.3.1.3 of AHRI 1230-2021 also specifies that if a common duct 
is used to measure airflow for multiple indoor units--if airflow is not 
individually measured for each indoor unit--these limits are calculated 
based on the sum of nominal capacities and nominal airflows for all of 
the indoor units connected to the common duct. Section 6.3.1.4 of AHRI 
1230-2021 specifies that these same provisions (in Section 6.3.1.3) 
apply for ducted indoor units, except that the airflow limit for ducted 
indoor units is 42 scfm per 1,000 Btu/h instead of 55 scfm per 1,000 
Btu/h. DOE surmises that the approach to maximum airflow rate provided 
in AHRI 1230-2021 represents the industry consensus regarding the most 
appropriate and representative maximum airflow rate for testing VRF 
multi-split systems. Therefore, DOE also surmises that Lennox's 
position on these provisions, expressed in the comments in response to 
the July 2017 ASHRAE TP RFI, changed while developing that industry 
consensus standard. As discussed, DOE is not proposing any deviations 
from the provisions in Section 6.3.1 of AHRI 1230-2021 regarding 
setting indoor airflow and ESP.
2. Condenser Head Pressure Controls
    Condenser head pressure controls regulate the flow of refrigerant 
through the condenser and/or adjust operation of condenser fans/water 
valves to prevent condenser pressures from dropping too low during low-
ambient operation. When employed, these controls ensure that the 
refrigerant pressure is high enough to maintain adequate flow through 
refrigerant expansion devices such as thermostatic expansion valves. 
The use of condenser head pressure controls impacts a unit's 
performance, making it important that this feature operate during 
testing because it would operate in the field. In the July 2017 ASHRAE 
TP RFI, DOE requested comment on the appropriateness of requiring head 
pressure control activation during testing of VRF multi-split systems. 
82 FR 34427, 34447.
    AHRI, Mitsubishi, and Carrier stated that head pressure controls 
should be activated during the test for VRF multi-split systems, as 
manufacturers have different algorithms for controlling head pressure 
and VRF multi-split systems cannot be maintained manually. (AHRI, No. 
11 at p. 35; Mitsubishi, No. 10 at p. 2, Carrier, No. 6 at p. 20) 
Goodman stated that head pressure control activation is not necessary 
for testing, as all VRF multi-split systems are variable speed, and 
system refrigerant pressures are kept at appropriate levels by 
controlling the compressor and outdoor fan speed. (Goodman, No. 14 at 
p. 7) Lennox stated that whether head pressure control is activated or 
not will have no impact on testing. (Lennox, No. 8 at p. 8)
    DOE also requested information regarding methods that could be 
added to the test procedure for VRF multi-split systems to be used if 
head pressure controls prevent stable operation at low-ambient, part-
load conditions, such as the special test provisions described in 
section F7.1 of AHRI 340/360-2015 for CUACs. 82 FR 34427, 34441, 34447. 
Specifically, DOE requested comment on whether a head pressure control 
activation requirement was appropriate for testing of VRF multi-split 
systems, as well as any additional methods that could be incorporated 
into the VRF multi-split system test procedure to calculate system 
efficiency if head pressure controls prevent stable operation at low-
ambient, part-load conditions. Id. In response, Goodman commented that 
there is no need for head pressure control activation when testing, 
and, therefore, no need to address head pressure control instability. 
(Goodman, No. 14 at p. 7) Carrier commented that VRF manufacturers need 
more time to evaluate the issue. (Carrier, No. 6 at p. 20)
    Section 5.2 of AHRI 1230-2021 specifies that units with head 
pressure controls have those controls enabled and operating in 
automatic control mode during testing, set at factory settings or per 
manufacturer installation instructions. Section 5.2.2 of AHRI 1230-2021 
also includes a head pressure control time average test, to be used if 
head pressure controls prevent a unit from achieving ``Stable 
Conditions'' as defined by the test standard. Sections 5.2.3 and 5.2.4 
provide additional direction for achieving stability, and are to be 
used if the tolerances for the head

[[Page 70655]]

pressure control time average test cannot be met. Absent any indication 
that activation of condenser head pressure controls results in test 
results that are unrepresentative or that such activation is unduly 
burdensome, DOE proposes adopting the AHRI 1230-2021 provisions 
specifying activation of head pressure controls during testing, with 
the additional clarification (in section 5.1 of the proposed appendix 
D1) that head pressure controls are to be set per manufacturer 
installation instructions or per factory settings if no instructions 
are provided. DOE is not proposing any additional deviations from the 
head pressure controls provisions in Section 5.2 of AHRI 1230-2021.
3. Indoor Unit Operation During Part-Load Tests
    When VRF multi-split systems operate at low cooling loads in field 
applications, typically only certain zones require cooling. Therefore, 
at low cooling loads VRF indoor units serving zones with no cooling or 
heating load typically turn off. In the July 2017 ASHRAE TP RFI, DOE 
requested information and data on the field operating states of indoor 
units of VRF multi-split systems when operating at low compressor 
speeds, near 25-percent load. 82 FR 34427, 34446.
    Commenters generally responded that applications vary greatly with 
load characteristics, so there is not one operation mode that is 
representative of all field scenarios, and therefore manufacturers 
should not be required to turn off any indoor units during the test. 
(AHRI, No. 11 at pp. 33-34; Goodman, No. 14 at p. 6; Mitsubishi, No. 10 
at p. 2; Carrier, No. 6 at pp. 18-19; Lennox, No. 8 at p. 7) 
Additionally, they commented that shutting off indoor units would 
require retesting and would add burden and variability to the test 
procedure. (Id.)
    Section 5.10 of AHRI 1230-2021 requires that the number of indoor 
units that are thermally active during full-load and part-load tests be 
in accordance with the STI, and that at least half of the total indoor 
units--as calculated per the total capacity of the connected indoor 
units--remain thermally inactive for the 25 percent load test. 
Furthermore, section 5.10 requires the following for thermally inactive 
indoor units: (1) Forced air circulation through the units shall be 
prevented (e.g., by blocking the inlet and outlet); and (2) the indoor 
unit control settings shall be set to ``OFF'' (e.g., by using remote or 
wireless thermostat). DOE surmises that AHRI's and industry's original 
positions on these provisions regarding inactive indoor units, as set 
forth in the comments in response to the July 2017 ASHRAE TP RFI, 
changed while developing the industry consensus standard in AHRI 1230-
2021. DOE is not proposing any deviations from the provisions regarding 
indoor units that are thermally active in Section 5.10 of AHRI 1230-
2021.
4. Transient Testing: Oil Recovery Mode
    VRF multi-split systems may periodically operate in an oil recovery 
mode to return oil from the refrigeration loop to the compressor. When 
undergoing oil recovery, the compressor(s) may increase operating 
speed, electronic expansion valves may open wider than normal, and 
indoor fans may be turned off, to allow more liquid refrigerant mass 
flow in the system. The higher refrigerant velocity helps to entrain 
the compressor oil that was blocked in the indoor refrigerant lines and 
return it to the compressor(s).
    The current DOE test procedure for VRF multi-split systems 
specifies through reference to ANSI/AHRI 1230-2010 that oil recovery 
mode should be activated if the system is designed to initiate the oil 
recovery mode more frequently than every two hours, but the test 
procedure does not specify a transient test method or other provisions 
specific to testing a unit with oil recovery. In the July 2017 ASHRAE 
TP RFI, DOE requested comment on the impact of oil recovery mode on 
power input and heating/cooling provided to space. 82 FR 34427, 34446 
(July 25, 2017). DOE also requested comment on whether any VRF multi-
split systems operate in oil recovery mode more frequently than every 
two hours of continuous operation. Id. For such systems, DOE requested 
comment on whether and how the test method should address the transient 
operation occurring during and after oil recovery. Id. In addition, DOE 
requested comment on the performance variation associated with oil 
level and whether all measurements should be made within a certain time 
after the last oil recovery. Id. AHRI, Mitsubishi, Goodman, and Lennox 
all commented that they did not support the incorporation of oil 
recovery into the test procedure. (AHRI, No. 11 at p. 34; Mitsubishi, 
No. 10 at p. 2; Goodman, No. 14 at p. 6; Lennox, No. 8 at p. 8) They 
stated that oil recovery seldom occurs, and only during periods of time 
at very low refrigerant flow rates, which would not be expected to 
occur during testing. (Id.)
    Section 5.1.3 of AHRI 1230-2021 specifies that oil recovery mode 
must be activated during test, regardless of the frequency of oil 
recovery cycles. If oil recovery occurs with a frequency that prevents 
a steady state test, AHRI 1230-2021 specifies the use of the transient 
test procedure as described in Section 8.8.3 (except Section 8.8.3.3) 
of ANSI/ASHRAE 37-2009, with modifications described in Section 5.1.3.1 
of AHRI 1230-2021. In light of the inclusion of oil recovery mode 
provisions in AHRI 1230-2021, DOE surmises that AHRI's and industry's 
original position on these conditions, as set forth in the comments in 
response to the July 2017 ASHRAE TP RFI, changed while developing AHRI 
1230-2021. DOE is not proposing any deviations from the provisions 
regarding oil recovery mode in Section 5.1.3 of AHRI 1230-2021.
5. Secondary Methods for Capacity Measurement
    Section 7.2.1 of ANSI/ASHRAE 37-2009 is referenced by AHRI 1230-
2021 and specifies the indoor air enthalpy method, plus an additional 
secondary method for calculating the test equipment capacity for all 
units with a rated cooling capacity less than 135,000 Btu/h. 
Additionally, Section 10.1.2 of ANSI/ASHRAE 37-2009 specifies that the 
secondary capacity measurement must agree with the primary capacity 
measurement to within 6 percent for equipment with cooling capacity 
less than 135,000 Btu/h. In the July 2017 ASHRAE TP RFI, DOE requested 
comment on the methods generally used for measurement of capacity for 
VRF multi-split systems and whether the selection of methods differs 
between cooling and heating tests. 82 FR 34427, 34447. DOE also 
requested comment on how to standardize the selection of test methods 
for measuring the capacity of VRF multi-split systems. Id.
    Commenters stated that there are challenges associated with 
secondary capacity methods for VRF multi-split systems, such as the 
refrigerant enthalpy and outdoor air enthalpy methods. (AHRI, No. 11 at 
p. 36; Carrier, No. 6 at p. 21) For example, AHRI stated that the 
refrigerant enthalpy method is not possible due to the range at which 
the flow meter would need to operate, and the fact that the presence of 
a metering device in the outdoor unit of some equipment would make it 
impossible to use a refrigerant flow meter. (Id.) AHRI further stated 
that the outdoor air enthalpy method is possible, but would require 
multiple code testers for testing more than one outdoor unit, or 
additional testing to cover multiple outdoor units tested together. 
(Id.) Carrier stated that for heat pump VRF systems, the outdoor air 
enthalpy may be used. (Carrier, No. 6 at p. 21) Carrier asserted that 
this method would be

[[Page 70656]]

straightforward for single module systems; however, with multiple 
module systems, testing would be very complex, if not impossible 
because the ability to measure air flow and capacity from various 
modules has not been achieved. (Id.) Carrier further stated that there 
is no adequate secondary method for VRF systems with heat recovery. 
(Id.) Carrier asserted that neither the refrigerant enthalpy nor 
outdoor air enthalpy methods would work due to the complexity of the 
refrigeration circuits in these units. (Id.)
    Section 5.1.1 of AHRI 1230-2021 requires that VRF multi-split 
systems be tested in accordance with ANSI/ASHRAE 37-2009, with 
additional instruction provided in appendix E of AHRI 1230-2021. 
Sections E9 and E13 of AHRI 1230-2021 include several modifications to 
secondary capacity measurement method provisions in ANSI/ASHRAE 37-
2009. Specifically, section E9 provides that when using the outdoor air 
enthalpy method as the secondary method, secondary checks are conducted 
for only the high temperature full load tests for cooling and heating 
mode. Section E13 modifies the outdoor air enthalpy method provisions 
in Section 8.6 of ANSI/ASHRAE 37-2009--e.g., section E13 specifies that 
the test used for capacity measurement for determination of efficiency 
metrics is the test without the outdoor air-side test apparatus 
connected to the outdoor unit. DOE surmises from the inclusion of these 
secondary method provisions in AHRI 1230-2021 that AHRI's and 
industry's original position on these conditions, as set forth in the 
comments in response to the July 2017 ASHRAE TP RFI, changed during the 
course of developing that industry consensus standard. DOE is not 
proposing any deviations from the provisions regarding secondary 
capacity measurement in appendix E of AHRI 1230-2021.
6. Heat Recovery
    Some VRF multi-split systems include a heat recovery control unit 
to control refrigerant flow between indoor units and provide heating 
and cooling to different conditioned spaces simultaneously. In the July 
2017 ASHRAE TP RFI, DOE requested comment on whether VRF multi-split 
systems with heat recovery capability can be operated without the heat 
recovery control unit attached, and if so, whether such systems are 
typically tested for determining EER, IEER, and COP with the heat 
recovery control unit attached. 82 FR 34427, 34447. DOE also sought 
data showing differences in test results with the heat recovery unit 
attached or unattached. Id.
    AHRI, Lennox, and Carrier commented that heat recovery units should 
be included during all tests for heat recovery systems. (AHRI, No. 11 
at p. 36; Lennox, No. 8 at p. 9; Carrier, No. 6 at p. 21) AHRI and 
Lennox stated that VRF heat recovery models cannot be operated without 
the heat recovery unit attached because the unit is an integral part of 
the system that cannot be removed, and, therefore, that the heat 
recovery unit should be accounted for in testing. (Id.)
    Section F2.3 of AHRI 1230-2021 specifies that individual models of 
VRF multi-split systems distributed in commerce with heat recovery 
components must be tested with the heat recovery components present and 
installed. Consistent with Section F2.3 of AHRI 1230-2021, DOE proposes 
at Sec.  429.43(a)(5) to specify that for basic models of VRF multi-
split systems distributed in commerce with heat recovery components, 
the manufacturer must determine represented values for the basic model 
based on performance of an individual model distributed in commerce 
with heat recovery components.

G. Specific Components

    An ASRAC working group for certain commercial heating, ventilating, 
and air conditioning (``HVAC'') equipment (``Commercial HVAC Working 
Group''),\15\ which included VRF multi-split systems, submitted a term 
sheet (``Commercial HVAC Term Sheet'') providing the Commercial HVAC 
Working Group's recommendations. (Docket No. EERE-2013-BT-NOC-0023, No. 
52) \16\ The Commercial HVAC Working Group recommended that DOE issue 
guidance under current regulations on how to test certain equipment 
features when included in a basic model, until the testing of such 
features can be addressed through a test procedure rulemaking. The 
Commercial HVAC Term Sheet listed the subject features under the 
heading ``Equipment Features Requiring Test Procedure Action.'' (Id at 
pp. 3-9) The Commercial HVAC Working Group also recommended that DOE 
issue an enforcement policy stating that DOE would exclude certain 
equipment with specified features from Departmental testing, but only 
when the manufacturer offers for sale at all times a model that is 
identical in all other features; otherwise, the model with that feature 
would be eligible for Departmental testing. These features were listed 
under the heading ``Equipment Features Subject to Enforcement Policy.'' 
(Id. at pp. 9-15)
---------------------------------------------------------------------------

    \15\ In 2013, members of ASRAC formed the Commercial HVAC 
Working Group to engage in a negotiated rulemaking effort regarding 
the certification of certain commercial HVAC equipment, including 
VRF multi-split systems. The Commercial HVAC Working Group's 
recommendations are available at www.regulations.gov under Docket 
No. EERE-2013-BT-NOC-0023-0052.
    \16\ Available at www.regulations.gov/document/EERE-2013-BT-NOC-0023-0052.
---------------------------------------------------------------------------

    On January 30, 2015, DOE issued a Commercial HVAC Enforcement 
Policy addressing the treatment of specific features during 
Departmental testing of commercial HVAC equipment. (See www.energy.gov/gc/downloads/commercial-equipment-testing-enforcement-policies) The 
Commercial HVAC Enforcement Policy stated that--for the purposes of 
assessment testing pursuant to 10 CFR 429.104, verification testing 
pursuant to 10 CFR 429.70(c)(5), and enforcement testing pursuant to 10 
CFR 429.110--DOE would not test a unit with one of the optional 
features listed for a specified equipment type if a manufacturer 
distributes in commerce an otherwise identical unit that does not 
include one of the optional features. (Id at p. 1) The objective of the 
Commercial HVAC Enforcement Policy is to ensure that each basic model 
has a commercially available version eligible for DOE testing, meaning 
that each basic model includes either a model without the optional 
feature(s) or a model with the optional features that is eligible for 
testing. Id. The features in the Commercial HVAC Enforcement Policy for 
VRF multi-split systems, (id at p. 5), align with the Commercial HVAC 
Term Sheet's list designated ``Equipment Features Subject to 
Enforcement Policy.''
    AHRI 1230-2021 includes Appendix F, ``Unit Configuration for 
Standard Efficiency Determination--Informative.'' Section F2.4 includes 
a list of features that are optional for testing. Section F2.4 of AHRI 
1230-2021 further specifies the following general provisions regarding 
testing of units with optional features:
     If an otherwise identical model (within the basic model) 
without the feature is not distributed in commerce, conduct tests with 
the feature according to the individual provisions specified in Section 
F2.4 of AHRI 1230-2021.
     For each optional feature, Section F2.4 of AHRI 1230-2021 
includes explicit instructions on how to conduct testing for equipment 
with the optional feature present.
    The optional features provisions in AHRI 1230-2021 are generally 
consistent with DOE's Commercial HVAC Enforcement Policy, but the

[[Page 70657]]

optional features in Section F2.4 of AHRI 1230-2021 do not align with 
the list of features included for VRF multi-split systems in the 
Commercial HVAC Enforcement Policy. For VRF multi-split systems, the 
Commercial HVAC Enforcement Policy specifies four optional features--
economizer, coated coil(s), steam/hydronic heat options, and 
dehumidification components. Of these, steam/hydronic heat options and 
coated coils are not included in the list of optional features in 
Section F2.4. DOE understands AHRI 1230-2021 to represent the industry 
consensus position on testing VRF multi-split systems. As such, DOE 
understands the industry consensus to be that steam/hydronic heat 
options and coated coils should not be treated as optional features for 
VRF multi-split systems and/or that VRF multi split systems are not 
distributed in commerce with these features.
    The list of optional features in Section F2.4 includes five 
features that are not present in the Commercial HVAC Enforcement Policy 
for VRF multi-split systems: low ambient cooling dampers, ventilation 
energy recovery systems (``VERS''), power correction capacitors, hail 
guards, and fresh air dampers. Three of these features in Section 
F2.4--low ambient cooling dampers, hail guards, and fresh air dampers--
are included for VRF multi-split systems in the ``Equipment Features 
Requiring Test Procedure Action'' section of the Commercial HVAC Term 
Sheet. The remaining two features--power correction capacitors and 
VERS--may be included in VRF multi-split systems distributed in 
commerce. Therefore, DOE has tentatively concluded that their inclusion 
as optional features for VRF multi-split systems is appropriate.
    DOE notes that the list of features and provisions in Section F2.4 
of appendix F of AHRI 1230-2021 conflates features that can be 
addressed by testing provisions with features that warrant enforcement 
relief (i.e., features that, if present on a unit under test, could 
have a substantive impact on test results and that cannot be disabled 
or otherwise mitigated). This differentiation was central to the 
Commercial HVAC Term Sheet, which as noted previously, included 
separate lists for ``Equipment Features Requiring Test Procedure 
Action'' and ``Equipment Features Subject to Enforcement Policy,'' and 
remains central to providing clarity in DOE's regulations. 
Specifically, models including features for which the impact can be 
addressed by testing provisions (e.g., UV lights, which can simply be 
turned off for testing) should be subject to testing and do not warrant 
enforcement relief (i.e., no provisions allowing representations based 
on performance of an otherwise identical model without the feature, and 
DOE compliance could be assessed based on testing of the model 
containing the feature and not based on testing of an otherwise 
identical model without the feature).
    Further, Section F2.4 of AHRI 1230-2021 does not provide provisions 
specific to how DOE would conduct enforcement testing with respect to 
specific components, as opposed to how manufacturers make 
representations. Therefore, provisions more explicit than those 
included in Section F2.4 of AHRI 1230-2021 are warranted to clarify (1) 
how manufacturers of VRF multi-split systems must make representations 
with regards to specific components; and (2) how DOE will conduct 
enforcement testing with respect to specific components (e.g., in which 
situations DOE would test a tested combination including individual 
indoor unit models with a specific component present).
    In order to provide clarity between test procedure provisions 
(i.e., how to test a specific unit) and certification and enforcement 
provisions (e.g., which model to test), DOE is not proposing to 
incorporate by reference appendix F of AHRI 1230-2021 and instead is 
proposing related provisions in appendix D1 to subpart F of part 431, 
Sec.  429.43, and Sec.  429.134. Specifically, in appendix D1, DOE 
proposes test provisions for specific components, including all of the 
components listed in Section F2.4 of 1230-2021. These provisions would 
specify how to test a unit with such a component (e.g., for a unit with 
hail guards, remove hail guards for testing). These proposed test 
provisions are consistent with the provisions in Section F2.4 of AHRI 
1230-2021 but include revisions for further clarity and specificity 
(e.g., adding clarifying provisions for how to test units with modular 
economizers as opposed to units shipped with economizers installed).
    In Sec.  429.43(a)(4), DOE is proposing provisions that would 
allow, in specific cases, determination of represented values for a 
tested combination of VRF multi-split system based on performance of a 
system without certain specific components. These provisions are 
generally consistent with the Commercial HVAC Term Sheet, the 
Commercial HVAC Enforcement Policy, and Section F2.4 of AHRI 1230-2021. 
However, unlike in Section F2.4 of AHRI 1230-2021 (but consistent with 
the Commercial HVAC Term Sheet and the Commercial HVAC Enforcement 
Policy) and as discussed earlier in this section, the components to 
which these provisions apply are limited to those components for which 
the test provisions for testing a unit with these components may result 
in differences in ratings compared to testing a unit without these 
components--specifically, air economizers and dehumidification 
components, which were included in both the Commercial HVAC Enforcement 
Policy for VRF multi-split systems and appendix F of AHRI 1230-2021.
    Also, because air economizers and dehumidification components are 
only ever installed as part of the indoor units of VRF multi-split 
systems, and VRF multi-split systems contain multiple indoor units with 
potentially distinct model numbers, DOE proposes to adopt language more 
specific to VRF multi-split systems than the language contained in the 
Commercial HVAC Enforcement Policy and Section F2.4 of AHRI 1230-2021--
i.e., applying the provisions to multiple indoor unit models and tested 
combinations. For example, DOE uses the term ``individual indoor unit 
models'' to account for potential discrepancies across individual 
indoor unit models that comprise the VRF multi-split system tested 
combination. This terminology allows for individual consideration of 
specific components on an indoor unit-by-indoor unit basis to account 
for scenarios in which one individual indoor unit model in the tested 
combination may have an ``otherwise identical'' indoor unit model while 
other individual indoor unit models in the tested combination may not 
have an ``otherwise identical'' indoor unit model.
    In summary, for air economizers and dehumidification components, 
DOE proposes the following:
     If the indoor unit model(s) in a tested combination within 
a basic model include only individual indoor unit models distributed in 
commerce with a specific component, or does not include any otherwise 
identical individual indoor unit models distributed in commerce without 
the specific component, the manufacturer must determine represented 
values for the tested combination based on performance of individual 
indoor unit models with the component present (and consistent with any 
relevant proposed test procedure provisions in appendix D1).
     If the indoor unit model(s) in a tested combination within 
a basic model include both individual indoor unit models distributed in 
commerce with a specific component and otherwise identical individual 
indoor unit models

[[Page 70658]]

distributed in commerce without the specific component, the 
manufacturer may determine represented values for the tested 
combination based on performance of individual indoor unit models 
either with the component present (and consistent with any relevant 
proposed test procedure provisions in appendix D1) or without the 
component present.
    DOE notes that in some cases, individual indoor unit models may 
include multiple of the specified components (i.e., both an economizer 
and dehumidification components) or there may be individual indoor unit 
models within a tested combination that include various 
dehumidification components that result in more or less energy use. In 
these cases, the represented values of performance must be 
representative of the lowest efficiency found within the indoor unit 
model(s) in a tested combination.
    Additionally, DOE is proposing at Sec.  429.43(b)(4) a 
certification reporting requirement for supplemental test instructions 
for VRF multi-split systems regarding specific components, 
corresponding to the proposed representation requirements for specific 
components at Sec.  429.43(a)(4). Specifically DOE proposes that the 
manufacturer must certify for which specific components (as listed in 
Sec.  429.43(a)(4)(i)), if any, the following provisions are 
applicable: (1) The indoor unit model(s) in a tested combination within 
a basic model include both individual indoor unit models distributed in 
commerce with the specific component and individual indoor unit models 
distributed in commerce without the specific component; (2) at least 
one of the individual indoor unit models distributed in commerce 
without the specific component is otherwise identical to any given 
individual indoor unit model distributed in commerce with the specific 
component; and (3) represented values for the tested combination are 
based on performance of individual indoor unit models distributed in 
commerce without the specific component.
    Also consistent with the Commercial HVAC Term Sheet and the 
Commercial HVAC Enforcement Policy, in 10 CFR 429.143(s)(1), DOE is 
proposing provisions regarding how DOE would test tested combinations 
within a basic model that include individual indoor unit models 
distributed in commerce with air economizers or dehumidification 
components. Specifically:
     If the manufacturer does not certify in accordance with 10 
CFR 429.43(b)(4) both that (1) indoor unit model(s) in a tested 
combination within a basic model include both individual indoor unit 
models distributed in commerce with a specific component and otherwise 
identical individual indoor unit models distributed in commerce without 
the specific component and (2) represented values for the tested 
combination are based on performance of individual indoor unit models 
distributed in commerce without the specific component; then DOE may 
test the tested combination with individual indoor unit models with the 
component present (and consistent with any relevant proposed test 
procedure provisions in appendix D1).
     If the manufacturer certifies in accordance with 10 CFR 
429.43(b)(4) both that (1) indoor unit model(s) in a tested combination 
within a basic model include both individual indoor unit models 
distributed in commerce with a specific component and otherwise 
identical individual indoor unit models distributed in commerce without 
the specific component, and (2) represented values for the tested 
combination are based on performance of individual indoor unit models 
distributed in commerce without the specific component, DOE will test 
the tested combination with otherwise identical indoor unit model(s) 
within the tested combination within a basic model that do not include 
the component, except in either of the following situations. In either 
of the following situations, DOE may test the tested combination with 
individual indoor unit models with the specific component present (and 
consistent with any relevant proposed test procedure provisions in 
appendix D1).
    [cir] DOE is not able, through documented reasonable effort, to 
obtain individual indoor unit models for testing that do not include 
the component.
    [cir] DOE becomes aware that the manufacturer's certification in 
accordance with 10 CFR 429.43(b)(4) regarding specific components is 
invalid.
    Were DOE to adopt the provisions in appendix D1, Sec.  429.43, and 
Sec.  429.134 as proposed, DOE would rescind the Commercial HVAC 
Enforcement Policy to the extent it is applicable to VRF multi-split 
systems. In a separate certification rulemaking, DOE may consider 
requiring a manufacturer to identify, in its certifications, the 
otherwise identical models that do not include specific component(s) 
that are tested to support representations of basic models that include 
individual models with specific components.
    Issue 2: DOE requests comment on its proposals in appendix D1, 
Sec.  429.43, and Sec.  429.134 regarding specific components.

H. Controls Verification Procedure

    Section 5.1.2.1 of AHRI 1230-2021 specifies that during steady-
state performance rating tests for cooling and heating efficiency, VRF 
multi-split systems must operate under commands from system controls 
except for certain components, referred to as ``critical parameters,'' 
which are allowed to be set by a manufacturer's representative. These 
critical parameters are (1) compressor speed(s), (2) outdoor fan 
speed(s), and (3) outdoor variable valve positions. Settings for 
critical parameters are allowed to be manually controlled using a 
manufacturer control tool, as opposed to all other components which 
must operate per commands from the system controls. The measured 
performance of VRF multi-split systems depends, in part, on the 
operating positions of each of these critical parameters. Accordingly, 
Section 5.1.2 of AHRI 1230-2021 states that operational settings for 
each of the critical parameters must be specified in the STI, and that 
each of the critical parameters must be allowed to be manually adjusted 
(to match the STI-certified values) during testing.
    AHRI 1230-2021 also includes a normative Appendix C that specifies 
a controls verification procedure (``CVP''). The purpose of the CVP is 
to validate that the observed positions of critical parameters during 
the CVP are within tolerance of the STI-certified critical parameter 
values that are set by the manufacturer in steady-state IEER cooling 
tests (see section III.H.5 of this NOPR for discussion of CVP results). 
This ensures that the measured results of the IEER test procedure are 
based on critical parameter settings that are representative of 
critical parameter behavior that would be experienced in the field.
    DOE proposes to adopt the CVP that is specified in appendix C of 
AHRI 1230-2021. Because the CVP is a verification procedure, not a test 
procedure used to develop represented values, DOE is proposing to 
distinguish the CVP as a validation procedure by adopting the CVP 
procedure in the product-specific enforcement provisions for VRF multi-
split systems at Sec.  429.134(s). The proposed inclusion of these 
provisions at Sec.  429.134(s) would indicate how DOE would conduct a 
CVP in the event of assessment or enforcement testing. The following 
sub-sections discuss the CVP and DOE's CVP-related proposals in detail.

[[Page 70659]]

1. Background
    DOE's current test procedure for VRF multi-split systems includes 
allowances in 10 CFR 431.96(f) for limited manufacturer involvement in 
assessment or enforcement testing. A manufacturer's representative may 
adjust components such as the compressor speed, fan speeds, and valve 
positions for the purposes of achieving steady-state conditions during 
testing. 10 CFR 431.96(f). This adjustment process is provided for VRF 
multi-split systems because of the complexity of VRF multi-split 
systems and the variety of settings needed to perform a test. 77 FR 
28928, 28946 DOE's current certification requirements for VRF multi-
split systems, found at Sec.  429.43(b)(4), specify that the STI must 
include compressor frequency set points and required dip switch/control 
settings for step or variable components. However, DOE's current 
regulations do not require these settings to match system behavior when 
the VRF multi-split system is operating under its own controls. 
Further, there are no constraints regarding the allowable range of 
adjustments that a manufacturer's representative may make to reach 
steady state. Sections 5.1.2 and 5.1.3 of ANSI/AHRI 1230-2010 allow 
similar adjustments of modulating components to achieve steady-state 
conditions during ratings tests.
    In October 2018, during the negotiation meetings of the Working 
Group, the CA IOUs raised concern with the representativeness of the 
ANSI/AHRI 1230-2010 method, particularly with respect to control inputs 
used at part-load test conditions. (Docket Nos. EERE-2018-BT-STD-0003-
0011 and EERE-2018-BT-STD-0003-0013) The CA IOUs presented field and 
laboratory test data indicating decreased performance at part-load 
conditions as compared to the part-load performance indicated by the 
IEER rating and available published performance data for that system 
when a VRF multi-split system was tested under commands from the system 
controls (i.e., not manually controlled). Id. The VRF TP Term Sheet 
from the Working Group recommended that DOE adopt an updated draft of 
AHRI 1230 that included a controls verification procedure as an 
appendix. (Docket No. EERE-2018-BT-STD-0003-0044 at pp. 1-2).
2. Purpose and Description
    As discussed, Appendix C of AHRI 1230-2021 establishes a CVP.\17\ 
The CVP verifies whether critical parameter settings certified in the 
STI, implemented by the manufacturer's representative during full-load 
and part-load steady-state cooling tests for IEER, are within the range 
of settings that would be used by the system during operation in the 
field--the system's native controls. The behavior of each critical 
parameter is monitored and recorded throughout the duration of a CVP.
---------------------------------------------------------------------------

    \17\ The concept for the CVP originated from a minimum 
compressor speed verification procedure provided in Japanese 
standard JIS B 8616:2006, Package Air Conditioners, which is 
included as an informative reference in appendix B of AHRI 1230-
2021, but not directly referenced within AHRI 1230-2021. Available 
at www.jsajis.org/index.php?main_page=product_info&cPath=2&products_id=13290.
---------------------------------------------------------------------------

    In contrast to steady-state tests in which test conditions are held 
constant, the CVP is a dynamic cooling test method in which certain 
test conditions are intentionally varied throughout the test. 
Specifically, the indoor room dry-bulb temperature is steadily 
decreased during the CVP using the room conditioning apparatus, in 
order to determine how the VRF multi-split system under test responds 
to approaching and achieving its setpoint. Outdoor room test conditions 
are held constant during the CVP. The CVP may be conducted at any of 
the four IEER outdoor air or entering water temperature conditions.
    At the start of the CVP, the indoor room test chamber temperature 
is controlled to a manufacturer-specified value that must be between 82 
[deg]F and 86 [deg]F, and the VRF indoor units are set to control to a 
constant indoor temperature, 80 [deg]F, except as explained by Section 
5.1.5 of AHRI 1230-2021. This Section provides instructions for 
adjusting the VRF indoor unit setpoints (deviating from 80 [deg]F) to 
account for set point bias and set point offset.\18\ VRF indoor units 
typically use the calculated temperature difference between the 
setpoint and the measured indoor air temperature as a control parameter 
for determining when to shut down and become thermally inactive. As 
discussed, the timing of the first indoor unit becoming thermally 
inactive dictates the allowable time period for determining whether 
certified critical parameter values have been validated, so it is 
crucial to account for set point bias and offset to ensure repeatable 
test results.
---------------------------------------------------------------------------

    \18\ AHRI 1230-2021 provides the following definitions for these 
terms in sections 3.29 and 3.30, respectively:
    Set Point Bias--The difference between 80 [deg]F and the nominal 
thermostat set point required for the thermostat to control for 80 
[deg]F sensed temperature at the sensed location.
    Set Point Offset--The difference between the temperature 
indicated by a thermostat's temperature sensor and the actual 
temperature at the sensor's location.
---------------------------------------------------------------------------

    After setting initial indoor air temperature, including any 
adjustments to control for set point bias and offset, the CVP proceeds 
by incrementally decreasing the indoor room test chamber temperature 
while the VRF multi-split system setpoint is held constant. As the 
indoor room temperature approaches and eventually passes below the VRF 
multi-split system setpoint, the VRF multi-split system controls should 
begin to register that the cooling demand has been satisfied, and the 
system will begin to ``unload,'' meaning reduce capacity.\19\ VRF 
multi-split systems typically unload by modulating component settings, 
including critical parameters, from the values used when providing 
full-load cooling capacity. During this unloading period and up until 
the time that the first indoor unit becomes thermally inactive, 
critical parameters are compared against the critical parameter values 
that are certified in the STI (validation criteria are discussed in a 
following section). Once the first indoor unit becomes thermally 
inactive, the indoor room dry bulb temperature continues decreasing 
until the indoor room reaches 77 [deg]F.
---------------------------------------------------------------------------

    \19\ Figure C.1 in AHRI 1230-2021 displays an example schematic 
of the indoor dry bulb temperature in [deg]F, compressor speed in 
Hz, and the number of thermally active indoor units over the 
duration of a CVP test.
---------------------------------------------------------------------------

3. Critical Parameter Definition
    Section 3.10 of AHRI 1230-2021 defines the term ``critical 
parameters'' as ``Key variables affecting the measured result,'' 
meaning ``[a]ny operating state or position for a component, either set 
manually or automatically by System Controls, which significantly 
impacts system performance.'' Section 5.1.2.1 of AHRI 1230-2021 limits 
the range of critical parameters that can be manually adjusted to 
compressor speed(s), outdoor fan speed(s) and outdoor variable valve 
position(s). To be more explicit that ``critical parameters'' refers 
only to those parameters specified by Section 5.1.2.1 of AHRI 1230-
2021, DOE is proposing not to reference the definition of critical 
parameters in Section 3.10 of AHRI 1230-2021, and instead to define the 
term ``critical parameter(s)'' in section 3 of appendix D1 as 
specifically referring to the following settings of modulating 
components of VRF multi-split air conditioners and heat pumps: 
Compressor speed(s), outdoor fan speed(s) and outdoor variable valve 
position(s). DOE has tentatively concluded that the proposed change to

[[Page 70660]]

the definition is editorial in nature and would not change or conflict 
with any testing provisions in AHRI 1230-2021.
    Issue 3: DOE requests comment on its proposed definition for 
``Critical Parameter(s)'', which specifies the three parameters that 
can be manually controlled in testing per Section 5.1.2.1 of AHRI 1230-
2021--compressor speed(s), outdoor fan speed(s), and outdoor variable 
valve position(s).
4. Critical Parameter Variation and Budget Method
    Appendix C of AHRI 1230-2021 includes methods for (1) calculating 
variation of critical parameters measured during the CVP from the 
values certified by the manufacturer in the STI (in Section C.4.4.2.3 
of AHRI 1230-2021); and for (2) assessing whether the variation of 
critical parameters from certified values is within acceptable limits 
(in Section C.6 of AHRI 1230-2021).
    Section C.4.4.2.3 of AHRI 1230-2021 provides instructions for 
calculating critical parameter variation during the CVP, specifying 
that at each measurement interval the instantaneous positions of all 
critical parameters are compared to the certified values. If multiple 
components corresponding to a single parameter are present (e.g., 
multiple compressors), the average position across all components is 
calculated at each measurement interval when determining variation. 
This difference is then divided by the maximum value observed during a 
full-load cooling CVP, to arrive at a normalized percent difference 
referred to as the ``Parameter Percent Difference'' or 
``PPDi,t'' in AHRI 1230-2021.
    Table C3 of AHRI 1230-2021 specifies weighting factors (referred to 
as ``nominal point values''), which are multiplied by the 
PPDi,t for each critical parameter. This results in a 
``Points'' value (calculated per equation C4 of AHRI 1230-2021) for 
each of the three critical parameters. These nominal point values 
reflect the relative sensitivity of IEER to changes in each critical 
parameter for VRF multi-split systems. The nominal point values 
specified in Table C3 of AHRI 1230-2021 are independent of the load 
point and whether the measured critical parameter is above or below the 
STI-certified value. Section C6.1.1 of AHRI 1230-2021 specifies that 
the Points values for each critical parameter are combined into a 
single measure called ``RSS Points Total'' using a root-sum-squared 
calculation. RSS Points Total represents an aggregated and normalized 
measure of deviation of all critical parameters from their certified 
values.
    The verification criteria specified in Section C.6 of AHRI 1230-
2021 for critical parameters measured during the CVP is a ``budget 
method'' that is dependent on cumulative variation across multiple 
critical parameters, instead of being solely dependent on the behavior 
of a single critical parameter. The budget method specified in Section 
C.6 of AHRI 1230-2021 applies a limit to the calculated RSS Points 
Total across all three critical parameters instead of applying 
individual tolerances to each individual critical parameter.\20\ This 
method allows manufacturers flexibility in critical parameter control 
strategies while still constraining the overall variation in VRF multi-
split system performance. The budget method can be applied the same way 
regardless of the number of critical parameters that a manufacturer 
certifies to their STI. For any critical parameter whose value is not 
certified in the STI, i.e., not designated as being controlled during 
the IEER cooling tests, the deviation in that parameter will be 
calculated as zero for the duration of the CVP.
---------------------------------------------------------------------------

    \20\ In addition to recommending inclusion of a CVP an appendix 
to the draft AHRI 1230, the VRF TP Term Sheet also recommended that 
DOE determine appropriate values for critical parameter tolerances 
using manufacturer-provided data. DOE subsequently conducted testing 
and sensitivity analysis of several VRF multi-split systems that 
were incorporated into the development of the ``budget method'' for 
CVP critical parameter verification specified in section C6 of AHRI 
1230-2021.
---------------------------------------------------------------------------

5. Validation of Certified Critical Parameters
    As discussed in the preceding section, AHRI 1230-2021 includes a 
budget method for calculating total variation in critical parameters 
from their certified values, expressed as a point total instead of 
measuring deviation individually for each critical parameter. Section 
C6.1.2 of AHRI 1230-2021 specifies that the certified critical 
parameters are valid if at least one measurement period of at least 
three minutes and a minimum of five sample readings exists where the 
average RSS Points Total is less than or equal to 70 points. Section 
C6.1.3 of AHRI 1230-2021 states that the manufacturer-specified 
critical parameters are invalid if no measurement period of at least 
three minutes and a minimum of five sample readings exists where the 
average RSS Points Total is less than or equal to 70 points. As 
discussed in section III.D.1 of this NOPR, the 70-point threshold was 
developed as part of AHRI 1230 Technical Committee meetings in which 
DOE presented anonymized and aggregated test data. As part of those 
meetings, DOE presented its finding that a minimum point budget of 32 
points was required to account for the lab-to-lab and test-to-test 
variability observed in critical parameter behavior between CVP runs 
for a single system. (EERE-2018-BT-STD-0003-0063 at p. 23). To allow 
for additional variability (e.g., sample-to-sample variability across 
the same VRF multi-split system and variability across different types 
of VRF multi-split systems), DOE recommended a 60-point budget to the 
Technical Committee. (Id). The Technical Committee ultimately agreed to 
provide a 70-point budget in AHRI 1230-2021.
    DOE has tentatively determined that the language in Sections C6.1.2 
and C6.1.3 of AHRI 1230-2021 could be construed and applied in multiple 
manners, and that this could lead to differing test burdens. The phrase 
``a measurement period of at least three minutes and a minimum of five 
sample readings'' could be understood to indicate a measurement period 
with no upper limit, potentially encompassing the entire duration of 
the CVP. This reading could be understood to require iterative 
calculations of time periods of varying lengths when validating 
critical parameters during the CVP (e.g., all three-minute periods, and 
all four-minute periods, and all five-minute periods). Taken to an 
extreme, this would result in thousands of calculations. Further, the 
language ``where the average RSS Points Total is less than or equal to 
70 points'' does not indicate the specific procedure for determining 
the average value of RSS Points Total--i.e., whether ``average'' refers 
to the average value within the measurement period or the cumulative 
average value of RSS points at the time of measurement.
    Therefore, DOE proposes to clarify these provisions by providing 
additional instructions for validating critical parameters in Sec.  
429.134(s)(3)(ii). Specifically, DOE proposes to specify that the 
duration of the time period used for validating critical parameters 
must be whichever of the following is longer: Three minutes or the time 
period needed to obtain five sample readings while meeting the minimum 
data collection interval requirements of Table C2 of AHRI 1230-2021. 
DOE also proposes to specify that if at least one measurement period 
(with the aforementioned duration) exists before the first indoor unit 
goes thermally inactive that has an average RSS Points Total less than 
or equal to 70 points, then the certified critical parameter values are 
validated.
    Issue 4: DOE seeks comment on its proposal for adding provisions at 
10

[[Page 70661]]

CFR 429.134(s)(3)(ii) to clarify the language in Sections C6.1.2 and 
C6.1.3 of AHRI 1230-2021 for validating critical parameters during a 
CVP, particularly pertaining to the duration of the measurement period 
used for validating critical parameters.
6. Determination of Alternate Critical Parameters
    AHRI 1230-2021 indicates that certified critical parameters shall 
be consistent with a valid CVP to be used for IEER testing. 
Specifically, Section 5.1.2.1 of AHRI 1230-2021 specifies that 
operational settings for critical parameters must be with RSS Points 
Total <=70 points, as defined in Section C6 of AHRI 1230-2021. However, 
AHRI 1230-2021 does not explicitly provide for alternate critical 
parameters for the IEER cooling test if the certified critical 
parameters are invalidated by the CVP.
    If a CVP is not conducted, or if a CVP is conducted and the 
manufacturer-specified critical parameters are validated, DOE proposes 
that the critical parameter values certified in the STI be used as the 
initial control inputs when conducting the IEER cooling test at the 
corresponding full- or part-load cooling condition. DOE understands 
this to be consistent with Section 5.1.2 of AHRI 1230-2021. Because 
AHRI 1230-2021 does not explicitly address how alternate critical 
parameters are to be determined in the case of a failed CVP, additional 
provisions are needed so that alternate critical parameters are 
determined in a repeatable and representative manner. Therefore, if the 
CVP invalidates the manufacturer-specified critical parameters, DOE 
proposes at Sec.  429.134(s)(3)(iii)(B) that alternate critical 
parameter values would be determined by averaging the value for each 
critical parameter from a specified time period of the CVP data, and 
that these alternate critical parameter values would be used for IEER 
testing in lieu of the certified critical parameter values. DOE 
proposes to use the same procedure for determination of measurement 
period length as is proposed in Sec.  429.134(s)(3)(ii)(A) and 
discussed in section III.H.5 of this NOPR: The longer of three minutes 
or the time period needed to obtain five sample readings while meeting 
the minimum data collection interval requirements of Table C2 of AHRI 
1230-2021.
    DOE also proposes to select the measurement period for determining 
alternate critical parameter values (with the aforementioned duration) 
that has the lower average RSS points total over the selected period 
than over any other period in the CVP having the same duration. If 
multiple such periods exist with the same RSS Points Total, DOE 
proposes to select the period closest to (but before) the time when the 
first indoor unit becomes thermally inactive (tOff).
    As described in section III.H.4 of this NOPR, Point Total 
represents an aggregated and normalized measure of deviation of all 
critical parameters from their certified values; therefore, by 
selecting a time period having the lowest average RSS Point Total, DOE 
would be selecting the period from the CVP where the alternate critical 
parameter values are most similar collectively to their certified 
values. However, DOE acknowledges that other approaches could be 
considered for selecting the measurement period for determination of 
alternate critical parameters from a CVP that has invalidated the 
critical parameter settings. For example, DOE could consider selecting 
the measurement period based on the behavior of compressor speed alone 
(e.g., the measurement period when deviation between certified and 
measured compressor speed is minimized), irrespective of other critical 
parameters. DOE could also consider selecting the measurement period 
based on test chamber conditions--e.g., the measurement period when the 
indoor test chamber first passes below the VRF multi-split system 
thermostat setpoint, or the measurement period just before the first 
indoor unit becomes thermally inactive.
    Issue 5: DOE seeks comment on its proposal to specify at Sec.  
429.134(s)(3)(iii)(B) how, in the event of a CVP that has invalidated 
the critical parameter settings, alternate critical parameters would be 
determined to use as initial control inputs during the corresponding 
IEER full- or part-load cooling test. DOE requests feedback on the 
proposed method for selecting a measurement period on the basis of 
minimized average RSS points total, and also on its proposal for using 
an average of critical parameter measurements over the selected 
measurement period to calculate alternate critical parameters. DOE will 
further consider any alternate approaches suggested by comments in 
developing any final rule.
7. When the CVP Is Conducted
    While appendix C of AHRI 1230-2021 details how to conduct a CVP, it 
does not include instruction about the circumstances in which a CVP 
must be conducted. As noted previously in section III.D.1, DOE is 
proposing to adopt appendix C from AHRI 1230-2021 as a product-specific 
enforcement provision, as opposed to adopting it in proposed appendix 
D1. In other words, DOE is not proposing that the CVP be conducted as 
part of an IEER test per the DOE test procedure. Instead, DOE is 
proposing to include the CVP (via reference to appendix C of AHRI 1230-
2021) as part of DOE's product-specific enforcement provisions for VRF 
multi-split systems in the proposed Sec.  429.134(s).
    Issue 6: DOE requests comment on its proposal to incorporate the 
CVP into its product-specific enforcement provisions for VRF multi-
split systems at Sec.  429.134(s) instead of the test procedure for VRF 
multi-split systems in the proposed appendix D1.
    In addition to its proposal to incorporate the CVP into its 
product-specific enforcement provisions, DOE is proposing to specify at 
Sec.  429.134(s)(3) that DOE would conduct a CVP at all of the four 
IEER cooling test conditions, consistent with the Working Group 
intention for DOE to verify controls performance. (Docket No. EERE-
2018-BT-STD-0003-0044 at p. 2) DOE also proposes to specify that the 
CVP would be performed first at the full-load cooling condition to 
determine maximum critical parameter values, before conducting the CVP 
at part-load cooling conditions because the maximum critical parameter 
values are used for calculating normalized deviation for CVPs at part-
load conditions.
    DOE also proposes to specify that the CVP would be performed on a 
single system from the two-system sample during enforcement testing. As 
discussed in section III.H.5 of this document, DOE's preliminary 
testing to evaluate repeatability and reproducibility of the CVP 
indicated that a minimum point budget of 32 points would be required to 
account for lab-to-lab and test-to-test variability observed in a 
single system. A 70-point budget could therefore accommodate an 
additional 48 points due to additional sources of variability, 
including sample-to-sample variability across the same VRF multi-split 
system. DOE has tentatively determined that the 70-point budget would 
be sufficient to account for all sources of variability during testing, 
such that conducting the CVP on a single system from the assessment/
enforcement sample would yield results that are representative of both 
systems in the sample.
    Should alternate critical parameters be required as a result of a 
CVP that has invalidated the critical parameter settings, DOE proposes 
that the alternate critical parameters would be determined from the CVP 
results of the single

[[Page 70662]]

system. These alternate critical parameters would be used for the 
corresponding IEER test (as specified in appendix D1) for all systems 
tested as part of the enforcement sample. Figure 1 shows a diagram 
illustrating DOE's proposed use of the CVP in its enforcement 
provisions for VRF multi-split systems.
    Issue 7: DOE requests comment on its proposed approach for 
conducting the CVP during enforcement testing. Specifically, DOE 
requests comment on the proposal that DOE would conduct the CVP for a 
single system during enforcement testing in order to validate the 
certified critical parameters. If commenters believe conducting the CVP 
on a single system as part of enforcement testing is insufficient, DOE 
requests test data demonstrating any issues with repeatability and 
reproducibility of the CVP that would indicate that the 70-point budget 
for critical parameter variation included in the industry consensus 
test procedure AHRI 1230-2021 is insufficient.
[GRAPHIC] [TIFF OMITTED] TP10DE21.009

I. Allowable Critical Parameter Adjustment

1. Adjustment of Certified Critical Parameter Values
    Section 6.3.3 of AHRI 1230-2021 provides instructions for adjusting 
critical parameters during the four specified full- or part-load IEER 
cooling test conditions in order to meet cooling capacity targets or to 
adjust SHR to below the allowable limit for the given IEER test point. 
Upon review of these provisions, DOE has tentatively determined that 
several amendments are required, and, therefore, proposes to include 
provisions to specify allowable critical parameter adjustments in 
section 5.2 of appendix D1 to subpart F of part 431.
    Section 6.3.3.1.2 of AHRI 1230-2021 specifies that in cases for 
which the cooling capacity is above the upper tolerance, the critical 
parameters are adjusted according to the instructions provided in the 
STI--specifically, the manufacturer may specify that any or all of the 
three critical parameters are to be adjusted in this scenario. Section 
6.3.3.1.2 further specifies that when adjusting critical parameters, 
the allowable adjustment is constrained by deviation resulting in an 
RSS points total of 70 points or fewer. However, this section does not 
explicitly describe RSS points total, nor does it refer to the 
provisions in Sections C4.4.2.3 and C6 that specify measurement and 
calculation of RSS points total in the context of a CVP. To remedy 
this, DOE is proposing instructions for calculating critical parameter 
variation (in terms of RSS Points Total) for steady-state IEER cooling 
tests for which the measured capacity is above the target load 
fraction. These proposed instructions are consistent with the 
provisions in Section C4.4.2.3 of AHRI 1230-2021 for calculating 
critical parameter variation in a CVP, except that DOE proposes to 
specify that the normalized deviation is to be measured between the 
certified STI values and the adjusted critical parameter values during 
steady-state IEER cooling tests, rather than between the certified STI 
values and an instantaneous measurement of critical parameter positions 
recorded during the CVP.
    DOE is proposing two other clarifications to the provisions for 
critical parameter adjustment for IEER tests in section 5 of appendix 
D1. First, DOE is proposing to clarify that upward adjustments to 
compressor speed (i.e., when the measured cooling capacity is too low 
or when the SHR is above the allowable limit) are not constrained by a 
budget on RSS Points Total. This is consistent with AHRI 1230-2021, 
which does not require an RSS Points Total budget be used for these 
adjustments.

[[Page 70663]]

Second, DOE proposes to clarify the instructions for calculating 
critical parameter variation in the scenario where a VRF multi-split 
system contains multiple components corresponding to a single critical 
parameter (e.g., multiple compressors). Specifically, DOE proposes to 
replace all references to ``multiple instances of a single parameter'' 
with ``multiple components corresponding to a critical parameter''. 
This proposal is consistent with AHRI 1230-2021, but clarifies the 
wording because ``multiple instances'' could be interpreted to refer to 
multiple time points for a single component, rather than multiple 
components at a given time, as intended.
    To the extent that the industry test procedure does not provide the 
specifications regarding adjustment of critical parameters as proposed, 
DOE tentatively finds that the industry test procedure would not ensure 
that measured results are comparative. Due to the potential variation 
resulting from the absence of the specification, the industry test 
procedure would not ensure that the results reflect the equipment's 
representative average energy efficiency or energy use. As such, DOE 
has initially determined, supported by clear and convincing evidence, 
that in the absence of the proposed specifications for adjustment of 
critical parameters the industry test procedure would not meet the 
statutory requirements of 42 U.S.C. 6314(a)(2)-(3), and, therefore, is 
proposing the supplemental specification.
    Issue 8: DOE seeks comment on its proposed provisions (to clarify 
similar provisions in AHRI 1230-2021) in section 4 of the proposed 
appendix D1 to subpart F of part 431 that specify allowable adjustments 
to critical parameters for IEER tests. Specifically, DOE requests 
feedback on its proposal to specify, for IEER tests for which the 
tested capacity is above the target capacity, calculation of normalized 
critical parameter variation during the adjustment process (similar to 
the calculation specified for the CVP in Section C4.4.2.3 of AHRI 1230-
2021).
2. Adjustment of Alternate Critical Parameter Values
    As described in section III.H.5 of this NOPR, in the case of 
critical parameter values being invalidated by the CVP conducted as 
part of DOE assessment or enforcement testing, DOE is proposing to 
clarify how alternate critical parameters would be determined for use 
as control inputs for a steady-state cooling test conducted at the 
corresponding IEER test condition (instead of using the critical 
parameter values certified in the STI). In such a case, it may still be 
necessary to adjust the alternate critical parameter values (determined 
in the CVP) in order to meet tolerances for capacity and SHR limits for 
the IEER test. Accordingly, DOE is proposing to include provisions at 
Sec.  429.134(s)(3)(iii)(B)(3) to indicate that in the case of 
invalidated critical parameter values in which DOE determines alternate 
critical parameters, additional adjustments to the alternate critical 
parameters are allowed to comply with capacity and/or SHR requirements. 
Specifically, DOE proposes to reference the methods for adjustment of 
critical parameters from section 5.2 of appendix D1 to subpart F of 
part 431 with two modifications. First, DOE proposes that in such a 
case, references in section 5.2 of appendix D1 to critical parameter 
values certified in the STI would be replaced with references to 
alternate critical parameter values determined under the CVP. Second, 
in such a case DOE proposes to determine the maximum operating state of 
each critical parameter (referred to as CPMax in AHRI 1230-
2021 and the proposed regulatory text) based on the maximum operating 
state observed during a CVP conducted at 100 percent cooling load 
conditions, instead of using the information certified to the STI for 
the 100 percent cooling load point.
    Issue 9: DOE seeks comment on the proposed provisions at Sec.  
429.134(s)(3)(iii)(B)(3) regarding allowable adjustment (to meet 
tolerances for capacity and SHR limits for an IEER test) of alternate 
critical parameter values determined by DOE in the event of a CVP that 
has invalidated the critical parameter settings.

J. Certification, Compliance and Enforcement

1. Represented Values
a. Tested Combination
    In the July 2017 ASHRAE TP RFI, DOE noted that Section 6.2.1 of the 
2015 draft version of AHRI 1230 included the following specification 
for tested combinations for systems with capacities greater than or 
equal to 65,000 Btu/h: Testing with standard 4-way ceiling cassette 
indoor units with the smallest coil volume per nominal capacity for 
non-ducted indoor units, and testing with mid-static units for ducted 
indoor units. 82 FR 34427, 34447. DOE also stated that there is a range 
of ductless indoor unit styles, which may have a range of efficiency 
characteristics, and that ducted systems may serve a range of ESPs. 82 
FR 34427, 34447-34448 (July 25, 2017). DOE requested comment and data 
on variation of system efficiency related to indoor unit styles (both 
for ducted and non-ducted indoor units). Id. at 82 FR 34448. DOE also 
requested data on the most prevalent style and static pressure 
classification (low-static, mid-static, or conventional-static) of 
ducted units. Id.
    AHRI, Carrier, Lennox, Mitsubishi, and Goodman commented that the 
4-way ceiling cassette and mid-static unit styles specified by the 2015 
draft version of AHRI 1230 for the tested combination of non-ducted and 
ducted indoor units, respectively, are the most common. (AHRI, No. 11 
at p. 36; Carrier, No. 6 at pp. 22; Lennox, No. 8 at p.10; Mitsubishi, 
No. 10 at p.3; Goodman, No. 14 at p.7) AHRI additionally stated that it 
had recently surveyed its members and confirmed that these types of 
indoor units are the most prevalent in the industry. (AHRI, No.11 at p 
36)
    Section 6.2 of AHRI 1230-2021 specifies tested combination 
requirements for VRF multi-split systems that generally align with the 
specifications from AHRI 1230-2015 draft, with a few amendments. First, 
AHRI 1230-2021 amends the instructions for determining which indoor 
units to use if the primary option is not offered by the manufacturer. 
Instead of relying on the ``highest sales volume'' designation for 
determining the alternate indoor units to compose the tested 
combination, Section 6.2.1.1 of AHRI 1230-2021 specifies the following 
hierarchy of non-ducted indoor units: Compact 4-way ceiling cassette, 
three-way cassette, two-way cassette, wall-mounted, one-way cassette, 
floor-mounted, and ceiling-suspended. Section 6.2.1.2 of AHRI 1230-2021 
specifies that the tested combination must use indoor units (with the 
lowest normalized coil volume) only from the indoor unit model family 
with the highest static capabilities. Second, AHRI 1230-2021 adds 
tested combination instructions for the new SDHV indoor unit model 
family. Specifically, Section 6.2.1.3 of AHRI 1230-2021 specifies that 
small-duct high velocity (SDHV) \21\ tested combinations must use 
indoor units

[[Page 70664]]

with the lowest normalized coil volume/motor efficiency.
---------------------------------------------------------------------------

    \21\ Section 3.17.3 of AHRI 1230-2021 defines the SDHV indoor 
unit model family to include indoor units that produce at least 1.2 
inches water column of ESP when operated at the full-load cooling 
airflow of at least 220 scfm per rated ton of nominal cooling 
capacity. These criteria align with DOE's definition for ``small-
duct high velocity system'' included in appendices M and M1 to 
subpart B of part 430, for consumer central air conditioners. The 
definition in Section 3.17.3 of AHRI 1230-2021 further provides 
additional clarification that the SDHV indoor unit model family is a 
separate indoor unit model family type that is not one of the ducted 
indoor unit model families.
---------------------------------------------------------------------------

    Although the tested combination is relevant to determination of 
represented values, rather than the method of test, DOE has tentatively 
determined that the AHRI 1230-2021 provisions regarding tested 
combination are appropriate. Therefore, for ease of use, DOE is 
proposing to incorporate by reference Section 6.2.1 of AHRI 1230-2021 
in appendix D1 to subpart F of part 431.
b. Represented Values for Indoor Unit Combinations
    DOE includes requirements for determining represented values for 
all commercial HVAC equipment (including VRF multi-split systems) in 
Sec.  429.43(a). Represented values for each VRF multi-split system 
basic model must be determined either through testing in conjunction 
with the applicable sampling provisions in Sec.  429.43(a)(1), or 
through application of an AEDM in accordance with the provisions in 
Sec.  429.43(a)(2). In addition, DOE's current test procedure 
incorporates by reference Section 5.2 of ANSI/AHRI 1230-2010, which 
includes requirements for determining represented values of VRF multi-
split systems through testing. However, DOE does not currently specify 
in Sec.  429.43(a) any provisions specific to VRF multi-split systems 
for determining represented values.
    In considering possible options for determining represented values 
for VRF multi-split systems, DOE reviewed AHRI 1230-2021, which 
includes provisions for determining represented values of VRF multi-
split systems through testing in Section 7. Section 7.2.5 specifies 
provisions pertaining to represented values of different combinations 
of indoor unit types. Specifically, for basic models that include only 
non-ducted or only ducted indoor unit combinations, Section 7.2.5.1 
states that ratings are determined by testing at least two complete 
system samples of the same combination of indoor units. Section 7.2.5.2 
states that for manufacturers who offer both non-ducted combinations 
and ducted combinations, ratings are determined by testing two or more 
combinations of indoor units with each outdoor unit, with one 
combination consisting of only non-ducted indoor units and the second 
combination consisting of only ducted indoor units. Additionally, 
Section 7.2.5.2.3 specifies that the rating given to any untested 
system with a mix of ducted and non-ducted units is to be set equal to 
the average of the ratings for the non-ducted and ducted tested 
combinations.
    As discussed in section III.J.1.a of this NOPR, Section 6.2 of AHRI 
1230-2021 includes provisions regarding tested combinations of three 
overall types: Non-ducted, ducted, and SDHV. However, Section 7.2.5 of 
AHRI 1230-2021 addresses only ducted and non-ducted combinations, and 
does not include provisions for determining represented values through 
testing of VRF multi-split systems with SDHV indoor units. While 
Section 7.2.2 of AHRI 1230-2021 states that mixed ratings must be 
determined by the straight average of two individual systems' rated 
values containing homogenous kinds of indoor units, including non-
ducted, ducted, and SDHV, Section 7.2.5 addresses mixed ratings of only 
non-ducted and ducted tested combinations.
    DOE proposes to adopt requirements at Sec.  429.43(a)(3)(iv)(B) for 
determining represented values for VRF multi-split systems that are 
consistent with the requirements from Section 7.2.5 of AHRI 1230-2021, 
but with additional detail to address SDHV indoor units and with 
language more appropriate for DOE's certification regulations. If a 
basic model includes only non-ducted indoor units, only ducted indoor 
units, or only SDHV indoor units, DOE proposes that the manufacturer 
must determine the represented values for the basic model by testing a 
sample of non-ducted tested combinations, ducted tested combinations, 
or SDHV tested combinations, as applicable, according to the sampling 
plan in Sec.  429.43(a)(1), or by application of an AEDM as specified 
in Sec. Sec.  429.43(a)(2) and 429.70. If a basic model includes more 
than one type of indoor unit combination--ducted, non-ducted, and/or 
SDHV--DOE proposes that the manufacturer must determine separate 
represented values for each type of indoor unit combination. DOE 
further proposes to specify that the represented values must be 
determined either through application of an AEDM, following provisions 
from Sec. Sec.  429.43(a)(2) and 429.70), or through testing a minimum 
of a single tested combination for each type of indoor unit combination 
included in that basic model.
    Additionally, DOE proposes that a manufacturer may determine 
represented values for optional ``mixed'' representations of any two 
required representations (i.e., ducted, non-ducted, and/or SDHV) for a 
basic model by calculating the mean of the two required 
representations. For example, if a basic model includes representations 
for ducted and non-ducted indoor unit combinations, an optional ``mixed 
ducted/non-ducted'' representation would be determined by averaging the 
ducted representation and the non-ducted representation.
    These proposals would only be required when certifying to amended 
standards in terms of IEER. DOE has tentatively determined that the 
proposed provisions would not be unduly burdensome to manufacturers. 
DOE typically requires manufacturers to follow the sampling plan in 
Sec.  429.43(a)(1) for all representations based on testing (i.e., a 
minimum of two test samples per represented value), rather than 
distributing the sampling plan testing requirements across a basic 
model with multiple representations (i.e., the proposed approach for 
requiring only a single tested system per representation). However, DOE 
has tentatively concluded that the test burden for VRF multi-split 
systems is significantly higher than that of other commercial AC 
equipment, which warrants the proposed reduced testing requirements for 
determining represented values. VRF multi-split systems are tested with 
up to twelve indoor units connected in a single refrigerant circuit, 
which requires additional set-up and commissioning time to install 
refrigerant piping and ensure proper charge compared to testing other 
kinds of commercial HVAC equipment. This often requires VRF multi-split 
systems to be tested using 2 indoor test chambers in order to 
accommodate all 12 indoor units, while other types of commercial HVAC 
equipment only ever require a single indoor test chamber.
    Further, DOE understands that most manufacturers of VRF multi-split 
systems offer both ducted and non-ducted indoor units for most basic 
models; therefore, for most basic models with representations based on 
testing, manufacturers would still be testing at least two samples 
(e.g., one with non-ducted indoor units and one with ducted indoor 
units). Consequently, DOE has tentatively concluded that the proposed 
reduced testing requirements will reduce test burden while being 
reasonably designed to produce test results which reflect energy 
efficiency of the VRF multi-split systems during a representative 
average use cycle. Of note, DOE's enforcement regulations in subpart C 
to part 429 apply to a basic model, not to a representation. Therefore, 
the entire basic model would be considered non-compliant if any of the 
representations for that basic model were found to be invalid.
    Issue 10: DOE requests comment on its proposals for determining 
represented values for VRF multi-split system basic models with 
different

[[Page 70665]]

indoor unit combinations. In particular, DOE seeks feedback on its 
proposal to allow for optional mixed representations of any two 
required representations (i.e., ducted, non-ducted, and/or SDHV) for a 
basic model by calculating the mean of the two required 
representations.
c. Multiple Refrigerants
    DOE recognizes that some commercial package air conditioning and 
heating equipment may be sold with more than one refrigerant option 
(e.g., R-410A or R-407C). Typically, manufacturers specify a single 
refrigerant in their literature for each unique model, but in its 
review, DOE has identified at least one commercial package air 
conditioning and heating equipment manufacturer that provides two 
refrigerant options under the same model number. The refrigerant chosen 
by the customer in the field installation may impact the energy 
efficiency of a unit. For this reason, DOE is proposing representation 
requirements applicable to models approved for use with multiple 
refrigerants. These proposals would only be required when certifying to 
amended standards in terms of IEER.
    Use of a refrigerant that requires different hardware (such as R-
407C as compared to R-410A) would represent a different basic model, 
and according to the current CFR, separate representations of energy 
efficiency are required for each basic model. In contrast, some 
refrigerants (such as R-422D, R-427A) would not require different 
hardware, and a manufacturer may consider them to be the same basic 
model, per DOE's current definition for ``basic model'' at Sec.  
431.92. In the latter case of multiple refrigerant options that do not 
require different hardware, DOE proposes at Sec.  429.43(a)(3)(iv)(A) 
that a manufacturer must determine the represented values (e.g., IEER, 
COP, and cooling capacity) for that basic model based on the 
refrigerant(s)--among all refrigerants listed on the unit's nameplate--
that result in the lowest cooling efficiency. These represented values 
would apply to the basic model for all refrigerants specified by the 
manufacturer as appropriate for use, regardless of which refrigerant 
may actually be used in the field.
    Issue 11: DOE requests comment on its proposal regarding 
representations for VRF multi-split system basic models approved for 
use with multiple refrigerants.
d. Confidence Limit
    DOE's regulations for commercial HVAC (including VRF multi-split 
systems) at Sec.  429.43(a)(1) include requirements for determining 
represented values based on a sample of tested units. Specifically, 
represented values for energy efficiency of a basic model of VRF must 
be less than or equal to the mean of the sample of tested units or the 
lower 95 percent confidence limit, whichever is lower.
    In a comment submitted in response to the July 2017 ASHRAE TP RFI, 
Lennox recommended that DOE harmonize the certification criteria in 10 
CFR 429.43 for ``commercial air conditioning products'' with that for 
central air conditioners, a consumer product, in 10 CFR 429.16 that 
uses only a 90 percent confidence interval. (Lennox, No. 8 at p. 6). In 
particular, Lennox stated that commercial equipment currently has a 
more stringent confidence limit of 95 percent and asserted that current 
testing technology does not support this level of precision. (Id.) 
Lennox's recommendation for a narrower confidence interval would 
decrease the level of certainty that a tested efficiency would be 
greater than the rated efficiency, assuming the same test sample size.
    Other manufacturers did not raise concerns regarding the confidence 
limit required for sampling commercial package air conditioners and 
heat pumps (including VRF multi-split systems), and Lennox did not 
provide data regarding variability of units in production and testing 
to support a different confidence limit. Absent more specific 
information or data regarding the stringency of the confidence level, 
DOE is not proposing to adopt the suggested change.\22\
---------------------------------------------------------------------------

    \22\ DOE notes that it has previously requested data regarding 
the variability of units of small, large, and very large air-cooled 
commercial package air conditioning and heating equipment in 
production and testing to enable DOE to review and make any 
necessary adjustments to the specified confidence levels. See 80 FR 
79655, 79659 (Dec. 23, 2015). However, DOE did not receive any 
relevant data in response to that request.
---------------------------------------------------------------------------

2. Certification Reporting Requirements
    DOE specifies certification reporting requirements for VRF multi-
split systems in 10 CFR 429.43(b). Certification reporting requirements 
for VRF multi-split systems include both public equipment-specific 
information and STI. In this NOPR, DOE is proposing changes to 
certification reporting requirements to enable testing to the updated 
industry test procedure AHRI 1230-2021 and to align with DOE's 
proposals regarding determination of represented values for VRF multi-
split systems, discussed previously in section III.J.1. DOE is 
proposing to amend the certification reporting requirements for VRF 
multi-split systems to address the IEER metric but is not proposing 
amendments to the current standards (in terms of EER). Therefore, the 
certification reporting requirement proposals would only apply when 
certifying to a future IEER standard; existing certification reporting 
requirements used when certifying to the current EER standards would 
not change unless DOE conducts a subsequent rulemaking amending the 
standard to rely on the IEER metric.
a. Certification Requirements
    In this NOPR, DOE proposes to amend the reporting requirements 
consistent with the proposed amendments to the test procedure and 
metric. When certifying a VRF multi-split system to standards in terms 
of IEER, manufacturers would be required to report the following public 
information in addition to the current certification requirements:
     IEER values (replacing the current certification 
requirement for EER values).
     The rated heating capacity, in Btu/h.
     The indoor unit combination used to determine the 
represented values for an individual combination (i.e., a non-ducted, 
ducted, SDHV, or mixed indoor unit combination), and all outdoor and 
indoor unit model numbers used to compose the tested combination. This 
proposal corresponds to the proposal regarding represented values for 
indoor unit combinations discussed in section III.J.1.b of this NOPR.
     The refrigerant used to determine the represented values 
for a basic model, per the proposal discussed in section III.J.1.c of 
this NOPR that manufacturers must determine all represented values for 
a basic model (e.g., EER, IEER, COP, and cooling capacity) based on the 
refrigerant listed on the unit's nameplate that results in the lowest 
cooling efficiency.
    Regarding heating capacity, DOE is proposing to include rated 
heating capacity in Btu/h (as measured according to the proposed 
amended test procedure in Appendix D1) as a public reporting 
requirement for all VRF multi-split heat pump systems (and not for VRF 
multi-split air conditioners). DOE's current certification reporting 
requirements for VRF multi-split systems at 10 CFR 429.43(b)(2) specify 
that manufacturers must include the rated cooling capacity (in Btu/h) 
and the rated cooling efficiency (EER, in Btu/W*h) in their public 
certification reports. For VRF multi-split heat pumps, the public 
certification report must also include the rated heating

[[Page 70666]]

efficiency (COP, in W/W), but the rated heating capacity is required to 
be reported as part of the STI instead of in the public certification 
report. DOE is proposing to require rated heating capacity as part of 
the public certification report instead of the STI to align with the 
certification approach for cooling capacity. As discussed in section 
III.E.1, manufacturers already test and rate VRF multi-split systems in 
the AHRI Directory of Certified Product Performance for VRF multi-split 
systems.\23\ AHRI requires that manufactures publicly provide the rated 
heating capacity of VRF multi-split systems at two separate outdoor 
temperature conditions, including at the 47 [deg]F outdoor temperature 
condition used in the proposed DOE test procedure. Because all VRF 
multi-split system manufacturers are AHRI members, DOE tentatively 
concludes that a requirement to report the rated heating capacity would 
not increase the reporting burden.
---------------------------------------------------------------------------

    \23\ The AHRI directory for VRF multi-split systems is available 
at: www.ahridirectory.org/NewSearch?programId=72&searchTypeId=3.
---------------------------------------------------------------------------

    Issue 12: DOE requests comment on its proposed certification 
reporting requirements for VRF multi-split systems.
    Manufacturers, including importers, must use product-specific 
certification templates to certify compliance to DOE. For VRF multi-
split systems, the certification template reflects the general 
certification requirements specified at 10 CFR 429.12 and the product-
specific public certification reporting requirements specified at Sec.  
429.43(b)(2). DOE is proposing to amend the product-specific public 
certification requirements for VRF multi-split systems in this notice. 
To help interested parties better appreciate these proposed changes, a 
draft certification template is included in the docket, which can be 
viewed as described in the Docket section at the beginning of this 
document and will be accessible on the DOE website.
b. Supplemental Testing Instructions
    The STI generally provides equipment-specific instruction to allow 
for third-party testing of equipment. DOE has tentatively determined 
that updates in the industry test procedure AHRI 1230-2021 require 
corresponding amendments to the STI certification requirements to test 
VRF multi-split systems. DOE proposes to add or amend the following 
items at Sec.  429.43(b)(4) as part of the required STI when certifying 
a VRF multi-split system to amended standards in terms of IEER, as 
these items would be needed for IEER testing per the proposed test 
procedure at appendix D1:
     Identification of the indoor units to be thermally active 
for each IEER test point;
     The rated indoor airflow for the full-load cooling, full-
load heating, and all part-load cooling tests (for each indoor unit), 
in standard cubic feet per minute (scfm);
     The indoor airflow-control setting to be used in the full-
load cooling test and the indoor airflow control setting to be used in 
the full-load heating test (for each indoor unit);
     For water-cooled units, the rated water flow rate in 
gallons per minute (gpm);
     System start-up or initialization procedures, including 
conditions and durations;
     The duration of the compressor break-in period. (Existing 
requirements in Sec.  431.96(c) require manufacturers to include this 
information in the test data underlying the certified ratings that must 
be maintained according to 10 CFR 429.71);
     Instructions for adjustment of critical parameters to meet 
capacity targets and/or SHR limits, including hierarchy for adjusting;
     The layout of the system set-up for testing (previously 
required upon request) including a piping diagram, setup instructions 
for indoor units and outdoor units, charging instructions, a control 
wiring diagram, and identification of the location of each critical 
parameter;
     Explicitly providing that the nominal cooling capacity and 
nominal heating capacity (if applicable) in British thermal units per 
hour (Btu/h) must be certified for each outdoor unit and indoor unit;
     Requiring testing instructions for conducting testing for 
all indoor unit combinations with distinct represented values within a 
basic model, as applicable. (This proposal corresponds to the proposal 
regarding represented values for indoor unit combinations discussed in 
section III.J.1.b of this NOPR);
     Removing the current requirement to report compressor 
frequency set points and instead require reporting operational settings 
for all critical parameters to be manually controlled for each of the 
four IEER cooling test conditions and for the COP heating test;
     Removing the reporting requirement regarding whether the 
model will operate at test conditions without manufacturer programming, 
because the proposed VRF enforcement provisions (discussed in section 
III.J of this NOPR) allow for a manufacturer representative to be on 
site for DOE testing;
     Removing the reporting requirement for rated static 
pressure, which is unnecessary because AHRI 1230-2021 includes ESP 
requirements for testing; and
     The frequency of oil-recovery cycles.
    Regarding the nominal cooling and heating capacity, DOE is also 
proposing to clarify that manufacturers must certify the nominal 
cooling capacity and nominal heating capacity (as applicable) for each 
indoor unit and outdoor unit as a part of their supplemental testing 
instructions. The existing STI requirements for VRF multi-split systems 
require reporting of ``nominal cooling capacity'' and ``rated heating 
capacity'', but do not specify whether these values need to be reported 
for the entire VRF multi-split system or for each indoor and outdoor 
unit. As described in section III.J.2.a, DOE is proposing to require 
public reporting of rated heating capacity for VRF multi-split heat 
pumps as part of the certification report. In sum, these proposals 
would require that manufacturers publicly certify the rated cooling 
capacity and rated heating capacity (as applicable) for each basic 
model of VRF multi-split system, and then separately certify (in 
supplemental testing instructions) the nominal cooling capacity and 
nominal heating capacity (as applicable) for each indoor unit and 
outdoor unit.
    Regarding the CVP, DOE also proposes to require reporting as part 
of the STI the following manufacturer-specified input conditions for 
conducting a CVP at each of the four IEER cooling test conditions: The 
required thermostat set points to ensure control for 80 [deg]F dry-bulb 
temperature when accounting for set point bias, the starting indoor 
dry-bulb temperature, and the indoor dry-bulb temperature ramp rate. 
This proposal corresponds to the proposal to adopt the CVP (as 
specified in Appendix C of AHRI 1230-2021) in Sec.  429.134(s), as 
discussed in section III.H of this NOPR.
    Regarding specific components, as discussed in section III.G of 
this NOPR, DOE is proposing an STI reporting requirement, corresponding 
to the proposed representation requirements for specific components at 
10 CFR 429.43(a)(4). Specifically DOE proposes that the manufacturer 
must certify for which, if any, specific components (as listed in 10 
CFR 429.43(a)(4)(i)) the following provisions are applicable: (1) The 
indoor unit model(s) in a tested combination within a basic model

[[Page 70667]]

include both individual indoor unit models distributed in commerce with 
the specific component and individual indoor unit models distributed in 
commerce without the specific component; (2) at least one of the 
individual indoor unit models distributed in commerce without the 
specific component is otherwise identical to any given individual 
indoor unit model distributed in commerce with the specific component; 
and (3) represented values for the tested combination are based on 
performance of individual indoor unit models distributed in commerce 
without the specific component.
    The proposed STI certification requirements provide information 
that is necessary for testing VRF multi-split systems consistent with 
the updated industry test procedure AHRI 1230-2021. Further, section D3 
of informative appendix D of AHRI 1230-2021 includes a list of 
recommended items to be included in STI when testing to AHRI 1230-2021, 
and most of the STI certification requirements proposed in this NOPR 
are included in the section D3 list. Therefore, DOE has tentatively 
concluded that the proposed STI certification requirements are 
warranted for testing according to the latest industry test procedure 
for VRF-multi-split systems and would not impose significant burden to 
manufacturers.
    Issue 13: DOE requests comment on its proposed STI reporting 
requirements for VRF multi-split systems.
3. Models Required for AEDM Validation
    As discussed, manufacturers of VRF multi-split systems may 
determine represented values through testing according to the sampling 
plan in Sec.  429.43(a)(1), or by application of an AEDM as specified 
in Sec. Sec.  429.43(a)(2) and 429.70. DOE proposes to adopt the 
following AEDM validation requirements for VRF multi-split systems to 
be similar to the sampling plan requirements for tested units, 
discussed in section III.J.3 of this NOPR.
    If a manufacturer makes representations for only a single type of 
indoor unit combination (i.e., ducted, non-ducted, or SDHV indoor unit 
combinations) within or across all its basic models to which the AEDM 
applies, DOE proposes that the manufacturer must validate the AEDM by 
testing at least a single tested combination of that type of indoor 
unit combination for each of the two selected basic models.
    If a manufacturer makes representations for two types of indoor 
unit combinations (i.e., ducted, non-ducted, and/or SDHV indoor unit 
combinations) within or across all its basic models to which the AEDM 
applies, DOE proposes that the manufacturer must test at least: (1) A 
single tested combination of a selected basic model as the first of 
those two types of indoor unit combination, and (2) a single tested 
combination of a different selected basic model as the second of those 
two types of indoor unit combination. For example, if an AEDM is 
validated through testing of two basic models (Model A and Model B) and 
Model A and Model B both include ducted and non-ducted indoor unit 
combinations, validation testing would need to be conducted on Model A 
with a ducted tested combination and Model B with non-ducted tested 
combination, or vice versa.
    If a manufacturer makes representations for all three types of 
indoor unit combinations (i.e., ducted, non-ducted, and SDHV indoor 
unit combinations) within or across all its basic models to which the 
AEDM applies, DOE proposes that the manufacturer must test at least a 
single tested combination of a selected basic model as a non-ducted 
tested combination and a single tested combination of a different 
selected basic model as a ducted tested combination. These proposals 
retain DOE's existing requirements for VRF multi-split systems at Sec.  
429.70(c)(iv) to test two basic models in order to validate an AEDM.
    DOE has tentatively concluded that the proposed AEDM validation 
requirements are consistent with AHRI 1230-2021, because they ensure 
that values developed with an AEDM conform to the results of AHRI 1230-
2021. These proposals would only be required when certifying to amended 
standards in terms of IEER.
    Issue 14: DOE requests comment on its proposal to amend its 
requirements for AEDM validation for VRF multi-split systems.
4. Manufacturer Involvement
    DOE does not allow manufacturer involvement in assessment and 
enforcement testing of most regulated equipment to ensure objectivity 
and repeatability. However, in acknowledgement of the uniquely 
complicated nature of VRF multi-split systems, the current DOE test 
procedure includes allowances in Sec.  431.96(f) for limited 
manufacturer involvement during assessment and enforcement testing. 77 
FR 28927, 28946. Specifically, a manufacturer's representative is 
allowed to witness assessment and enforcement testing, inspect set-up, 
discuss set-up with a DOE representative, and adjust modulating 
components to achieve steady-state operation. Sec.  431.96(f). In AHRI 
1230-2021, allowable manufacturer involvement is prescribed in Sections 
5.1.2 and 6.3.3.
    Section 5.1.2 states that manufacturer authorized personnel may 
support commissioning of the VRF multi-split system being tested (i.e., 
ensuring that the system is properly installed and functioning as 
expected). Section 5.1.2.1 states that operational settings for 
critical parameters may be manually adjusted and shall be as specified 
in the STI but does not specify which party is responsible for setting 
the critical parameters during testing. Section 5.1.2.2 states that all 
compressors shall initially operate at the setting(s) provided in the 
STI, which is redundant with Section 5.1.2.1. Section 5.1.2.3 states 
that all control settings must be set by a member of the laboratory and 
states that all control settings must remain unchanged for all load 
points once system setup has been completed.
    Section 6.3.3 specifies allowable critical parameter adjustments 
for the purposes of meeting capacity targets and/or SHR limits during 
IEER cooling tests. However, Section 6.3.3 includes unclear and 
contradictory language regarding who performs critical parameter 
adjustments. Specifically, Section 6.3.3 describes critical parameter 
``adjustments'' as being performed by laboratory personnel, but also 
specifies that when a steady-state test is conducted in a third-party 
laboratory, a manufacturer's representative may ``set'' critical 
parameter values under the supervision of the third-party laboratory 
(using the service tool to monitor critical parameters). Further, 
Section 6.3.3 uses several different terms when describing who takes 
certain actions as part of adjusting critical parameters, for which it 
is unclear if any difference in meaning is intended: ``the lab'', ``a 
member of the laboratory'', ``lab personnel'', and ``the third party 
laboratory''.
    Given the importance of explicitly specifying the specific actions 
the manufacturer's representative can take as part of assessment and 
enforcement testing of VRF multi-split systems, DOE does not propose to 
adopt Sections 5.1.2 and 6.3.3 of AHRI 1230-2021, and instead proposes 
to specify in Sec.  429.134(s)(2) provisions for allowable manufacturer 
involvement during DOE assessment and enforcement testing. These 
provisions are generally consistent with Sections 5.1.2 and 6.3.3 of 
AHRI 1230-2021, but assign more

[[Page 70668]]

precisely the actions that a manufacturer's representative may take.
    Specifically, DOE is proposing to clarify that a manufacturer's 
representative is allowed to support commissioning of the VRF multi-
split system and to witness DOE assessment or enforcement testing, 
which is consistent with the current Federal test procedure. For all 
cooling and heating tests, DOE proposes that all control settings other 
than critical parameters must be set by a member of the third-party 
laboratory; a manufacturer's representative may initially set all 
critical parameters to their certified values. For IEER cooling tests 
only, DOE proposes to specify that if additional adjustments to 
critical parameters are required for meeting capacity targets and/or 
SHR limits (see section III.I of this NOPR), a manufacturer's 
representative may make such adjustments in accordance with section 5.1 
of appendix D1 using a proprietary control tool. DOE further proposes 
that initial setting and any additional critical parameter adjustments 
performed by a manufacturer's representative during IEER testing must 
be monitored by third-party laboratory personnel using a service tool. 
For the heating test, DOE proposes that the manufacturer's 
representative would not be permitted to make any critical parameter 
adjustments during testing and would only be allowed to initially set 
critical parameters to their certified values. These proposals are a 
departure from the current DOE test procedure (which allows 
manufacturer control of modulating components for the purposes of 
reaching steady-state operation) and instead align with the latest 
industry test procedure AHRI 1230-2021 (with minor clarifications in 
wording, as discussed).
    In the case that a manufacturer is not present for assessment or 
enforcement testing, third-party laboratory personnel may need a 
manufacturer's control tool to set critical parameters to their initial 
settings or make additional adjustments required by the test procedure. 
Accordingly, DOE is proposing to amend its test notice requirements for 
VRF multi-split systems at Sec.  429.110(b)(1)(iv) to require 
manufacturers to include a means of control to set and adjust critical 
parameters with all systems provided for enforcement testing. 
Correspondingly, DOE is proposing provisions for VRF multi-split 
systems at Sec.  429.104(b) that would require manufacturers to provide 
a means of control for assessment testing, although manufacturers would 
not be required to provide the VRF multi-split system for assessment 
testing. This proposal would enable the laboratory staff to perform 
IEER and heating tests in the event that a manufacturer's 
representative is not available for assessment and/or enforcement 
testing. DOE also proposes that, if a manufacturer's representative is 
not present for testing, a member of the third-party laboratory shall 
set and adjust critical parameter values in accordance with section 5.1 
of appendix D1 using the means of control provided by the manufacturer 
in response to the test notice.
    Issue 15: DOE seeks comment on its proposal to require a means of 
control to be provided by the manufacturer for assessment and 
enforcement testing.
    Furthermore, AHRI 1230-2021 only partially addresses allowable 
manufacturer involvement during the CVP. Specifically, section C3.1 
provides instructions that control settings must be identical to those 
used during the steady-state IEER tests, except that control settings 
for critical parameters shall not be controlled during the CVP. 
However, Appendix C to AHRI 1230-2021 does not provide instruction for 
which parties may interact with the unit under test, and under what 
circumstances. Also, the wording ``identical to those used during the 
steady-state IEER tests'' could be interpreted to mean that steady-
state IEER tests must be conducted prior to a CVP, which should not be 
necessary. To address these issues, DOE proposes to specify in its 
product-specific enforcement provisions at Sec.  429.134(s)(2) that a 
manufacturer's representative is allowed to support commissioning of 
the VRF multi-split system and witness the CVP. DOE also proposes to 
specify that the control settings used during a CVP must be set by a 
member of the third-party laboratory and must be set per the provisions 
in section 5.1 of appendix D1 to subpart F of part 431 (except for 
critical parameters, which must operate automatically from the system 
controls and must not be controlled or adjusted at any point during the 
CVP).
    DOE has tentatively concluded that these proposals would ensure the 
consistency and objectivity of the CVP. Furthermore, these proposals 
are consistent with AHRI 1230-2021, because they ensure the 
manufacturer's representative cannot set or adjust any parameters in 
the CVP that AHRI 1230-2021 specifies shall operate under commands from 
system controls during the CVP. Additionally, the proposed language to 
set control settings for the CVP (except critical parameters) in 
accordance with section 5.1 of appendix D1 to subpart F of part 431 
ensures that the same control settings (except critical parameters) are 
used between the CVP and IEER cooling tests, without requiring IEER 
cooling tests to be conducted before a CVP.
    Issue 16: DOE seeks comment on its proposal to establish in 10 CFR 
429.134(s)(2) provisions regarding allowable manufacturer involvement 
during assessment and enforcement testing, which are consistent with 
AHRI 1230-2021. DOE also seeks comment on its proposal for allowable 
manufacturer involvement during the CVP.
5. Certified Critical Parameter Operational Settings
    As described in section III.J.2.b of this NOPR, DOE is proposing to 
require that manufacturers certify in the STI the operational settings 
for all critical parameters to be manually controlled for each of the 
four IEER cooling test conditions and for the COP heating test. Because 
the control settings for critical parameters affect the operating state 
of the VRF multi-split system, the measured performance is likely to 
vary significantly based on the critical parameter settings selected. 
For example, in preliminary testing, DOE determined that a 10 percent 
change in compressor speed resulted in an average difference of 
approximately 5 EER points (in Btu/W*hr) at each IEER load point. 
(EERE-2018-BT-STD-0003-0063 at p. 15). Due to the relationship of 
critical parameter operational settings to the measured performance of 
VRF multi-split systems, DOE is making several proposals related to the 
certified critical parameters.
    As discussed in section III.H.5, DOE is proposing to use the CVP 
during assessment and enforcement testing to verify that the certified 
critical parameter values for IEER cooling tests are valid. The 
certified critical parameter values used for the heating test are not 
subject to validation from a CVP, as the CVP is applicable only for 
cooling operation. In addition to its proposals governing the use of 
the CVP, DOE is proposing to add a certification reporting provision 
specific to VRF multi-split systems in Sec.  429.43(b)(5). This 
proposal specifies that if a manufacturer becomes aware that any of the 
certified operational settings for the critical parameters are 
determined to be invalid according to the results of a CVP, whether 
that CVP be performed by the manufacturer or another party, the 
manufacturer would be required to re-certify the operational settings 
of those critical parameters for all affected basic models, as well as 
re-rate and re-certify the affected basic models. Notably, DOE is not 
proposing a requirement that

[[Page 70669]]

manufacturers conduct the CVP as part of certification to DOE.
    In addition to its proposal to require re-certification and re-
rating of VRF multi-split systems in the event a manufacturer becomes 
aware that any of its certified operational settings for critical 
parameters are invalid according to a CVP, DOE also proposes to amend 
the enforcement testing requirements at Sec.  429.110(a) to state that 
DOE may initiate enforcement testing for VRF multi-split systems if DOE 
has reason to believe that the model is not in compliance, has invalid 
certified operational settings for critical parameter values, or has an 
otherwise invalid certified rating. Under this proposal DOE may 
initiate enforcement testing to investigate the certified critical 
parameter values and the associated IEER rating for VRF multi-split 
systems based on any of the following events:
    1. DOE conducts CVP during assessment testing that results in 
invalidated operational settings for critical parameters for a basic 
model;
    2. DOE conducts assessment testing for IEER and COP that creates 
reason to believe the basic model would be non-compliant with energy 
conservation standards or have an otherwise invalid rating;
    3. Another party conducts a CVP that results in invalidated 
operational settings for critical parameters for a basic model and the 
manufacturer fails to recertify that basic model;
    4. A CVP is conducted (by DOE or another party) that results in 
invalidated operational settings for critical parameters for a basic 
model, and DOE finds that a similar basic model from the same 
manufacturer relies on similar certified operational settings for 
critical parameters.
    DOE may examine multiple sources including, but not limited to, 
publicly available information and the STI when determining whether 
there is reason to proceed to enforcement testing. DOE notes that upon 
initiation of enforcement testing, DOE will issue a test notice to the 
manufacturer to acquire the selected models and means of control, and 
will conduct a CVP on the certified operational settings of critical 
parameters before proceeding to IEER testing.
    Issue 17: DOE requests comment on its proposed approaches for 
certification and for enforcement testing in the event that a VRF 
multi-split system has invalid certified operational settings for 
critical parameter values.
6. Enforcement Sampling Plan
    DOE's regulations at Sec.  429.110(e) include provisions for 
selection of units for enforcement testing. Specifically, Sec.  
429.110(e)(2) states that for commercial air conditioners and heat 
pumps (which includes VRF multi-split systems), DOE will use an initial 
sample size of not more than four (4) units when determining a basic 
model's compliance with applicable energy conservation standards. As 
described in section III.J.1.b of this NOPR, DOE has tentatively 
determined that the testing of VRF multi-split systems is significantly 
more involved than the testing of other commercial HVAC equipment. The 
proposed test procedure would incorporate instructions for setting the 
positions of multiple critical parameters during testing, which 
requires additional setup as compared to other kinds of commercial HVAC 
equipment. DOE estimates the cost to test VRF multi-split systems to be 
between $7,500 and $27,000, depending on size and configuration of the 
system (not including costs of copper piping or refrigerant). 
Additionally, DOE is proposing in this NOPR to incorporate the CVP into 
its enforcement regulations for VRF multi-split systems at Sec.  
429.134(s), which would add approximately eight hours of test time at 
each of the four IEER load conditions during enforcement testing.
    Because of the involved nature of testing VRF multi-split systems, 
it would be unlikely that DOE would conduct assessment testing or 
enforcement testing on the maximum number of units currently specified 
(i.e., four). In order to reflect what would be the expected practice, 
DOE proposes to amend its enforcement sampling plan requirements 
specific to VRF multi-split systems to require a sample size of two VRF 
multi-split systems. The process for determining compliance with energy 
conservation standards would be unchanged in this proposal, i.e., a 
compliance determination would be made for VRF multi-split systems 
using the sampling plan found in appendix B to subpart C of part 429 
with a first sample size of n1 = 2 VRF multi-split systems.
    Issue 18: DOE requests comment on its proposed enforcement sampling 
plan for VRF multi-split systems.

K. Test Procedure Costs

    EPCA requires that the test procedures for commercial package air 
conditioning and heating equipment, which includes VRF multi-split 
systems, be those generally accepted industry testing procedures or 
rating procedures developed or recognized by AHRI or by ASHRAE, as 
referenced in ASHRAE Standard 90.1. (42 U.S.C. 6314(a)(4)(A)) Further, 
if such an industry test procedure is amended, DOE must amend its test 
procedure to be consistent with the amended industry test procedure, 
unless DOE determines, by rule published in the Federal Register and 
supported by clear and convincing evidence, that such amended test 
procedure would not meet the requirements in 42 U.S.C. 6314(a)(2) and 
(3) related to representative use and test burden. (42 U.S.C. 
6314(a)(4)(B)) In this NOPR, DOE proposes to amend the current test 
procedure for VRF multi-split systems at Sec.  431.96 by (1) 
incorporating by reference AHRI 1230-2021 and ANSI/ASHRAE 37-2009; and 
(2) establishing provisions for determining IEER for VRF multi-split 
systems. DOE also proposes to amend its certification, compliance, and 
enforcement (``CCE'') provisions for VRF multi-split systems to provide 
information that is necessary for testing VRF multi-split systems 
consistent with the updated industry test procedure AHRI 1230-2021. 
Most significantly, these proposed changes include the incorporation of 
the CVP from AHRI 1230-2021 into DOE's product-specific enforcement 
provisions at Sec.  429.134, as well as accompanying certification 
requirements at Sec.  429.43.
    DOE has tentatively determined that these proposed amended test 
procedures would be representative of an average use cycle and would 
not be unduly burdensome for manufacturers to conduct. The proposed 
appendix D, measuring EER and COP per ANSI/AHRI 1230-2010, does not 
contain any changes from the current Federal test procedure, and, 
therefore, would not require retesting solely as a result of DOE's 
adoption of this proposed amendment to the test procedure, if made 
final. The proposed test procedure in appendix D1, measuring IEER and 
COP per AHRI 1230-2021, would lead to an increase in cost from appendix 
D testing. DOE estimates that the cost for third-party lab testing 
according to the proposed appendix D1 for measuring IEER and COP to be 
$7,500--$27,000 per VRF multi-split heat pump system, depending on size 
and configuration.
    As discussed in section II, the proposed test procedure provisions 
regarding IEER would not be mandatory unless DOE amends the energy 
conservation standards for VRF multi-split systems based on IEER. But, 
DOE has tentatively determined that the proposed test procedure 
amendments would not be expected to increase the testing burden on VRF 
multi-split

[[Page 70670]]

system manufacturers. All VRF multi-split system manufacturers are AHRI 
members; DOE is referencing the prevailing industry test procedure that 
was established for use in AHRI's certification program (which DOE 
presumes will be updated to include IEER in terms of the latest 
industry test procedure AHRI 1230-2021). Therefore, DOE expects that 
manufacturers will begin testing using the test methods in AHRI 1230-
2021, and the testing burden will already be incurred from AHRI members 
participating in AHRI's certification program. Additionally, DOE has 
tentatively determined that the test procedure amendments, if 
finalized, would not require manufacturers to redesign any of the 
covered equipment, would not require changes to how the equipment is 
manufactured, and would not impact the utility of the equipment.
    Issue 19: DOE requests comment on its understanding of the impact 
of the test procedure proposals in this NOPR, specifically DOE's 
initial conclusion that the proposed DOE test procedure amendments, if 
finalized, would not increase testing burden on VRF multi-split system 
manufacturers, compared to current industry practice as indicated by 
AHRI 1230-2021.

L. Reserved Appendices for Test Procedures for Commercial Air 
Conditioning and Heating Equipment

    DOE is proposing to relocate and centralize the current test 
procedures for VRF multi-split systems to a new appendix D to subpart F 
of part 431. As proposed, appendix D would not amend the current test 
procedures. Appendix D would continue to reference ANSI/AHRI 1230-2010 
and provide instructions for determining EER and COP. Correspondingly, 
DOE is proposing to update the existing incorporation by reference of 
ANSI/AHRI 1230-2010 at Sec.  431.95 so that the incorporation by 
reference applies to appendix D. Appendix D would also centralize the 
additional test provisions currently applicable under Sec.  431.96--
Sec.  431.96(c) through (f). VRF multi-split systems would be required 
to be tested according to appendix D, absent amendments to the 
applicable energy conservation standards to rely on the IEER metric.
    DOE also proposes to adopt the updated version of AHRI 1230, AHRI 
1230-2021, including the IEER metric in a new appendix D1 to subpart F 
of part 431. VRF multi-split systems would not be required to test 
according to appendix D1 until compliance is required with amended 
energy conservation standards that rely on the IEER metric, should DOE 
adopt such standards.

M. Compliance Date

    EPCA prescribes that, if DOE amends a test procedure, all 
representations of energy efficiency and energy use, including those 
made in the context of certification and on marketing materials and 
product labels, must be made in accordance with that amended test 
procedure, beginning 360 days after publication of such a test 
procedure final rule in the Federal Register. (42 U.S.C. 6314(d)(1))
    EPCA also provides an allowance for individual manufacturers to 
petition DOE for an extension if the manufacturer may experience undue 
hardship in meeting the deadline. (42 U.S.C. 6314(d)(2)) To receive 
such an extension should DOE finalize an amended test procedure, 
petitions must be filed with DOE no later than 60 days before the end 
of the 360-day period and must detail how the manufacturer will 
experience undue hardship. (Id.)

IV. Procedural Issues and Regulatory Review

A. Review Under Executive Order 12866

    The Office of Management and Budget (``OMB'') has determined that 
this test procedure rulemaking does not constitute a ``significant 
regulatory action'' under section 3(f) of Executive Order (``E.O.'') 
12866, Regulatory Planning and Review, 58 FR 51735 (Oct. 4, 1993). 
Accordingly, this action was not subject to review under the Executive 
order by the Office of Information and Regulatory Affairs (``OIRA'') in 
OMB.

B. Review Under the Regulatory Flexibility Act

    The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires 
preparation of an initial regulatory flexibility analysis (``IRFA'') 
for any rule that by law must be proposed for public comment, unless 
the agency certifies that the rule, if promulgated, will not have a 
significant economic impact on a substantial number of small entities. 
As required by Executive Order 13272, ``Proper Consideration of Small 
Entities in Agency Rulemaking,'' 67 FR 53461 (August 16, 2002), DOE 
published procedures and policies on February 19, 2003, to ensure that 
the potential impacts of its rules on small entities are properly 
considered during the DOE rulemaking process. 68 FR 7990. DOE has made 
its procedures and policies available on the Office of the General 
Counsel's website: www.energy.gov/gc/office-general-counsel.
    DOE reviewed this proposed rule under the provisions of the 
Regulatory Flexibility Act and the procedures and policies published on 
February 19, 2003. DOE certifies that the proposed rule, if adopted, 
would not have significant economic impact on a substantial number of 
small entities. The factual basis of this certification is set forth in 
the following paragraphs.
    DOE is proposing amendments to the test procedures for VRF multi-
split systems to satisfy its statutory requirements under EPCA to 
remain consistent with updates to the applicable industry test 
procedure and to re-evaluate its test procedures at least once every 7 
years. (42 U.S.C. 6314(a)(4)(A) and (B); 42 U.S.C. 6314(1)(A))
    DOE proposes to update Sec.  431.96 ``Uniform test method for the 
measurement of energy efficiency of commercial air conditioners and 
heat pumps,'' as follows: (1) Incorporate by reference AHRI 1230-2021 
and ANSI/ASHRAE 37-2009 (including Errata Sheet issued October 3, 
2016); and (2) establish provisions for determining IEER for VRF multi-
split systems. DOE proposes to add new appendices D and D1 to subpart F 
of part 431, both entitled ``Uniform test method for measuring the 
energy consumption of variable refrigerant flow multi-split air 
conditioners and heat pumps (other than air-cooled with rated cooling 
capacity less than 65,000 Btu/h),'' (``appendix D'' and ``appendix 
D1'', respectively). The current DOE test procedure for VRF multi-split 
systems would be relocated to appendix D without change, and the new 
test procedure adopting AHRI 1230-2021 would be established in appendix 
D1 for determining IEER. Compliance with appendix D1 would not be 
required until compliance is required with amended energy conservation 
standards for VRF multi-split systems that rely on IEER, should DOE 
adopt such standards.
    DOE also proposes to update its certification, compliance, and 
enforcement (``CCE'') provisions for VRF multi-split systems to provide 
information that is necessary for testing VRF multi-split systems 
consistent with the updated industry test procedure AHRI 1230-2021. 
Most significantly, these proposed changes include the incorporation of 
the controls verification procedure (``CVP'') from AHRI 1230-2021 into 
DOE's product-specific enforcement provisions at Sec.  429.134, as well 
as accompanying certification requirements at Sec.  429.43. DOE is also 
proposing to amend the sampling size requirements for enforcement from 
``a maximum of not

[[Page 70671]]

more than four units'' to specifying testing of two units.
    The proposed rule, if adopted, would not have significant economic 
impact on a substantial number of small entities. For manufacturers of 
VRF multi-split systems, the Small Business Administration (``SBA'') 
has set a size threshold, which defines those entities classified as 
``small businesses'' for the purposes of the statute. 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. The 
equipment covered by this rule is classified under North American 
Industry Classification System (``NAICS'') code 333415,\24\ ``Air-
Conditioning and Warm Air Heating Equipment and Commercial and 
Industrial Refrigeration Equipment Manufacturing.'' DOE used the SBA's 
small business size standards to determine whether any small entities 
would be subject to the requirements of the rule. DOE identified 
manufacturers using DOE's Compliance Certification Database \25\ and 
the AHRI database.\26\ DOE identified ten original equipment 
manufacturers (``OEMs'') of the covered equipment.
---------------------------------------------------------------------------

    \24\ 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 July 16, 2021).
    \25\ DOE's Compliance Certification Database is available at: 
www.regulations.doe.gov/ccms (last accessed May 10, 2021).
    \26\ The AHRI Database is available at: https://www.ahridirectory.org/ (last accessed May 10, 2021).
---------------------------------------------------------------------------

    In reviewing the ten OEMs, DOE did not identify any companies that 
met the SBA criteria for a small entity because they surpassed the 
SBA's employee threshold. Therefore, DOE tentatively concludes that the 
proposed rule would not have a significant economic impact on a 
substantial number of small entities. DOE welcomes public comment on 
this certification conclusion.
    Issue 20: DOE requests comment on its assessment that there are no 
small businesses that are OEMs of VRF multi-split systems.
    Issue 21: DOE requests comment on its conclusion that the proposed 
rule would not have significant impacts on a substantial number of 
small manufacturers.
    DOE has submitted a certification and supporting statement of 
factual basis to the Chief Counsel for Advocacy of the Small Business 
Administration for review under 5 U.S.C. 605(b).

C. Review Under the Paperwork Reduction Act of 1995

    Manufacturers of VRF multi-split systems 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 procedure, including 
any amendments adopted for that test procedure. DOE has established 
regulations for the certification and recordkeeping requirements for 
all covered consumer products and commercial equipment, including VRF 
multi-split systems. (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''), and 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.
    Under EPCA, DOE's energy conservation program consists essentially 
of four parts: (1) Testing, (2) labeling, (3) Federal energy 
conservation standards, and (4) certification and enforcement 
procedures. For covered equipment, relevant provisions of the Act 
include definitions (42 U.S.C. 6311), energy conservation standards (42 
U.S.C. 6313), test procedures (42 U.S.C. 6314), labeling provisions (42 
U.S.C. 6315), and the authority to require information and reports from 
manufacturers (42 U.S.C. 6316).
    DOE's certification and compliance activities ensure accurate and 
comprehensive information about the energy and water use 
characteristics of covered products and covered equipment sold in the 
United States. Manufacturers of all covered products and covered 
equipment must submit a certification report before a basic model is 
distributed in commerce, annually thereafter, and if the basic model is 
redesigned in such a manner to increase the consumption or decrease the 
efficiency of the basic model such that the certified rating is no 
longer supported by the test data. Additionally, manufacturers must 
report when production of a basic model has ceased and is no longer 
offered for sale as part of the next annual certification report 
following such cessation. DOE requires the manufacturer of any covered 
product or covered equipment to establish, maintain, and retain the 
records of certification reports, of the underlying test data for all 
certification testing, and of any other testing conducted to satisfy 
the requirements of 10 CFR part 429, and 10 CFR part 431. Certification 
reports provide DOE and consumers with comprehensive, up-to date 
efficiency information and support effective enforcement.
    DOE requires manufacturers or their party representatives to 
prepare and submit certification reports and compliance statements 
using DOE's electronic Web-based tool, the CCMS, which is the primary 
mechanism for submitting certification reports to DOE. CCMS currently 
has product and equipment specific templates which manufacturers are 
required to use when submitting certification data to DOE. DOE believes 
the availability of electronic filing through the CCMS system reduces 
reporting burdens, streamlines the process, and provides DOE with 
needed information in a standardized, more accessible form. This 
electronic filing system also ensures that records are recorded in a 
permanent, systematic way.
    DOE is proposing to amend the reporting requirements for VRF multi-
split systems as discussed in section III.J.2. DOE sent a revised 
information collection approval to OMB under the existing Control 
Number 1910-1400. The revision only reflects the changes proposed in 
this rulemaking as an amendment to the existing information collection.
    DOE is proposing that respondents must submit electronic forms 
using DOE's online CCMS. DOE's CCMS is publicly accessible at 
www.regulations.doe.gov/ccms, and includes instructions for users, 
registration forms, and the product-specific reporting templates 
required for use when submitting information to CCMS.
    DOE has tentatively determined that the proposed amendments would 
not impose additional costs for manufacturers of VRF multi-split 
systems because manufacturers of this equipment are already submitting 
certification reports to DOE and as part of testing to the proposed 
amended test procedure (which references the updated industry test 
procedure AHRI 1230-2021) should have readily available the information 
that DOE is proposing to collect as part of this rulemaking. DOE also 
tentatively determines that manufacturers would rely on existing record 
keeping systems to maintain the additional information reported.
    Issue 22: DOE invites public comment on: (1) Whether the proposed 
information collection requirements are necessary for the performance 
of DOE's functions, including whether the information will have 
practical utility;

[[Page 70672]]

(2) the accuracy of DOE's estimates of the burden of the proposed 
information collection requirements; (3) ways to enhance the quality, 
utility, and clarity of the information to be collected; and (4) ways 
to minimize the burden of the information collection requirements on 
respondents.
    Comments should be addressed to the Department of Energy Desk 
Officer, Office of Information and Regulatory Affairs, OMB, 725 17th 
Street NW, Washington, DC 20503. Persons submitting comments to OMB 
also are requested to send a copy to the contact person at the address 
given in the FOR FURTHER INFORMATION CONTACT section of this notice of 
proposed rulemaking. Interested persons may obtain a copy of the DOE's 
Paperwork Reduction Act Submission to OMB from the contact person named 
in this notice of proposed rulemaking. 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 NOPR, DOE proposes test procedure amendments that it 
expects will be used to develop and implement future energy 
conservation standards for VRF multi-split systems. 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 (Aug. 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 has examined this proposed rule and has 
determined that it would 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 proposed 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, 
the proposed 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 proposed regulatory action likely to result in a rule that may 
cause the expenditure by State, local, and Tribal governments, in the 
aggregate, or by the private sector of $100 million or more in any one 
year (adjusted annually for inflation), section 202 of UMRA requires a 
Federal agency to publish a written statement that estimates the 
resulting costs, benefits, and other effects on the national economy. 
(2 U.S.C. 1532(a), (b)) The UMRA also requires a Federal agency to 
develop an effective process to permit timely input by elected officers 
of State, local, and Tribal governments on a 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 proposed 
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 proposed rule would 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

[[Page 70673]]

(March 18, 1988), that this proposed regulation would not result in any 
takings that might require compensation under the Fifth Amendment to 
the U.S. Constitution.

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

    Section 515 of the Treasury and General Government Appropriations 
Act, 2001 (44 U.S.C. 3516 note) provides for agencies to review most 
disseminations of information to the public under guidelines 
established by each agency pursuant to general guidelines issued by 
OMB. OMB's guidelines were published at 67 FR 8452 (Feb. 22, 2002), and 
DOE's guidelines were published at 67 FR 62446 (Oct. 7, 2002). Pursuant 
to OMB Memorandum M-19-15, Improving Implementation of the Information 
Quality Act (April 24, 2019), DOE published updated guidelines which 
are available at www.energy.gov/sites/prod/files/2019/12/f70/DOE%20Final%20Updated%20IQA%20Guidelines%20Dec%202019.pdf. DOE has 
reviewed this proposed 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 proposed 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 proposed significant energy action, 
the agency must give a detailed statement of any adverse effects on 
energy supply, distribution, or use should the proposal be implemented, 
and of reasonable alternatives to the action and their expected 
benefits on energy supply, distribution, and use.
    The proposed regulatory action to amend the test procedure for 
measuring the energy efficiency of VRF multi-split systems 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 proposed modifications to the test procedure for VRF multi-
split systems would incorporate testing methods contained in certain 
sections of the following commercial standards: AHRI 1230-2021, ASHRAE 
37-2009. DOE has evaluated these standards and is unable to conclude 
whether they fully comply with the requirements of section 32(b) of the 
FEAA (i.e., whether they were developed in a manner that fully provides 
for public participation, comment, and review). DOE will consult with 
both the Attorney General and the Chairman of the FTC concerning the 
impact of this test procedure on competition, prior to prescribing a 
final rule.

M. Description of Materials Incorporated by Reference

    In this NOPR, DOE proposes to incorporate by reference the 
following test standards:
    (1) The test standard published by AHRI titled ``2021 Standard for 
Performance Rating of Variable Refrigerant Flow (VRF) Multi-Split Air-
Conditioning and Heat Pump Equipment,'' AHRI Standard 1230-2021. AHRI 
Standard 1230-2021 is an industry-accepted test procedure for measuring 
the performance of VRF multi-split systems. AHRI Standard 1230-2021 is 
available on AHRI's website www.ahrinet.org/search-standards.aspx.
    (2) The test standard published by ASHRAE, titled ``Methods of 
Testing for Rating Electrically Driven Unitary Air-Conditioning and 
Heat Pump Equipment,'' ANSI/ASHRAE Standard 37-2009 (including Errata 
Sheet issued October 3, 2016). ANSI/ASHRAE Standard 37-2009 is an 
industry-accepted test procedure that provides a method of test for 
many categories of air conditioning and heating equipment. ANSI/ASHRAE 
Standard 37-2009 is available on ANSI's website at webstore.ansi.org/RecordDetail.aspx?sku=ANSI%2FASHRAE+Standard+37-2009.
    (3) The test standard published by AHRI titled, ANSI/AHRI Standard 
1230-2010, ``2010 Standard for Performance Rating of Variable 
Refrigerant Flow (VRF) Multi-split Air-Conditioning and Heat Pump 
Equipment,'' approved August 2, 2010 and updated by addendum 1 in March 
2011. ANSI/AHRI Standard 1230-2010 is an industry-accepted test 
procedure for measuring the performance of VRF multi-split systems. 
ANSI/AHRI Standard 1230-2010 is available on AHRI's website 
www.ahrinet.org/search-standards.aspx.

V. Public Participation

A. Participation in the Webinar

    The time and date of the webinar are listed in the DATES section at 
the beginning of this document. If no participants register for the 
webinar, it will be cancelled.
    Webinar registration information, participant instructions, and 
information about the capabilities available to webinar participants 
will be published on DOE's website: https://www1.eere.energy.gov/buildings/appliance_standards/standards.aspx?productid=71&action=viewlive. Participants are 
responsible for ensuring their systems are compatible with the webinar 
software.
Procedure for Submitting Prepared General Statements for Distribution
    Any person who has an interest in the topics addressed in this 
notice, or who is representative of a group or class of persons that 
has an interest in these issues, may request an opportunity to make an 
oral presentation at the webinar. Such persons may submit to 
[email protected]. Persons who wish to speak 
should include with their request a computer file in WordPerfect, 
Microsoft Word, PDF, or text (ASCII) file format that briefly describes 
the nature of their interest in this rulemaking and the topics they 
wish to discuss. Such persons should also provide a daytime telephone 
number where they can be reached.

[[Page 70674]]

    Persons requesting to speak should briefly describe the nature of 
their interest in this rulemaking and provide a telephone number for 
contact. DOE requests persons selected to make an oral presentation to 
submit an advance copy of their statements at least two weeks before 
the webinar. At its discretion, DOE may permit persons who cannot 
supply an advance copy of their statement to participate, if those 
persons have made advance alternative arrangements with the Building 
Technologies Office. As necessary, requests to give an oral 
presentation should ask for such alternative arrangements.

B. Conduct of the Webinar

    DOE will designate a DOE official to preside at the webinar/public 
meeting and may also use a professional facilitator to aid discussion. 
The meeting will not be a judicial or evidentiary-type public hearing, 
but DOE will conduct it in accordance with section 336 of EPCA (42 
U.S.C. 6306). A court reporter will be present to record the 
proceedings and prepare a transcript. DOE reserves the right to 
schedule the order of presentations and to establish the procedures 
governing the conduct of the webinar/public meeting. There shall not be 
discussion of proprietary information, costs or prices, market share, 
or other commercial matters regulated by U.S. anti-trust laws. After 
the webinar/public meeting and until the end of the comment period, 
interested parties may submit further comments on the proceedings and 
any aspect of the rulemaking.
    The webinar/public meeting will be conducted in an informal, 
conference style. DOE will present a summary of the proposals, allow 
time for prepared general statements by participants, and encourage all 
interested parties to share their views on issues affecting this 
rulemaking. Each participant will be allowed to make a general 
statement (within time limits determined by DOE), before the discussion 
of specific topics. DOE will permit, as time permits, other 
participants to comment briefly on any general statements.
    At the end of all prepared statements on a topic, DOE will permit 
participants to clarify their statements briefly. Participants should 
be prepared to answer questions by DOE and by other participants 
concerning these issues. DOE representatives may also ask questions of 
participants concerning other matters relevant to this rulemaking. The 
official conducting the webinar/public meeting will accept additional 
comments or questions from those attending, as time permits. The 
presiding official will announce any further procedural rules or 
modification of the above procedures that may be needed for the proper 
conduct of the webinar/public meeting.
    A transcript of the webinar/public meeting will be included in the 
docket, which can be viewed as described in the Docket section at the 
beginning of this notice. In addition, any person may buy a copy of the 
transcript from the transcribing reporter.

C. Submission of Comments

    DOE will accept comments, data, and information regarding this 
proposed rule no later than the date provided in the DATES section at 
the beginning of this proposed rule. Interested parties may submit 
comments using any of the methods described in the ADDRESSES section at 
the beginning of this document.
    Submitting comments via www.regulations.gov. The 
www.regulations.gov web page will require you to provide your name and 
contact information. Your contact information will be viewable to DOE 
Building Technologies staff only. Your contact information will not be 
publicly viewable except for your first and last names, organization 
name (if any), and submitter representative name (if any). If your 
comment is not processed properly because of technical difficulties, 
DOE will use this information to contact you. If DOE cannot read your 
comment due to technical difficulties and cannot contact you for 
clarification, DOE may not be able to consider your comment.
    However, your contact information will be publicly viewable if you 
include it in the comment or in any documents attached to your comment. 
Any information that you do not want to be publicly viewable should not 
be included in your comment, nor in any document attached to your 
comment. Persons viewing comments will see only first and last names, 
organization names, correspondence containing comments, and any 
documents submitted with the comments.
    Do not submit to www.regulations.gov information for which 
disclosure is restricted by statute, such as trade secrets and 
commercial or financial information (hereinafter referred to as 
Confidential Business Information (``CBI'')). Comments submitted 
through www.regulations.gov cannot be claimed as CBI. Comments received 
through the website will waive any CBI claims for the information 
submitted. For information on submitting CBI, see the Confidential 
Business Information section.
    DOE processes submissions made through www.regulations.gov before 
posting. Normally, comments will be posted within a few days of being 
submitted. However, if large volumes of comments are being processed 
simultaneously, your comment may not be viewable for up to several 
weeks. Please keep the comment tracking number that www.regulations.gov 
provides after you have successfully uploaded your comment.
    Submitting comments via email. Comments and documents submitted via 
email also will be posted to www.regulations.gov. If you do not want 
your personal contact information to be publicly viewable, do not 
include it in your comment or any accompanying documents. Instead, 
provide your contact information on a cover letter. Include your first 
and last names, email address, telephone number, and optional mailing 
address. The cover letter will not be publicly viewable as long as it 
does not include any comments.
    Include contact information each time you submit comments, data, 
documents, and other information to DOE. No faxes will be accepted.
    Comments, data, and other information submitted to DOE 
electronically should be provided in PDF (preferred), Microsoft Word or 
Excel, WordPerfect, or text (ASCII) file format. Provide documents that 
are not secured, written in English and free of any defects or viruses. 
Documents should not contain special characters or any form of 
encryption and, if possible, they should carry the electronic signature 
of the author.
    Campaign form letters. Please submit campaign form letters by the 
originating organization in batches of between 50 to 500 form letters 
per PDF or as one form letter with a list of supporters' names compiled 
into one or more PDFs. This reduces comment processing and posting 
time.
    Confidential Business Information. Pursuant to 10 CFR 1004.11, any 
person submitting information that he or she believes to be 
confidential and exempt by law from public disclosure should submit via 
email two well-marked copies: One copy of the document marked 
confidential including all the information believed to be confidential, 
and one copy of the document marked non-confidential with the 
information believed to be confidential deleted. DOE will make its own 
determination about the confidential status of the information and 
treat it according to its determination.

[[Page 70675]]

    It is DOE's policy that all comments may be included in the public 
docket, without change and as received, including any personal 
information provided in the comments (except information deemed to be 
exempt from public disclosure).

D. Issues on Which DOE Seeks Comment

    Although DOE welcomes comments on any aspect of this proposal, DOE 
is particularly interested in receiving comments and views of 
interested parties concerning the following issues:
    Issue 1: DOE requests feedback on its proposal to adopt IEER as 
determined under AHRI 1230-2021 in the Federal test procedure for VRF 
multi-split systems. DOE also seeks comment on its proposed amendment 
to the definition for IEER at Sec.  431.92 to distinguish between the 
test procedures for ACUACs and VRF multi-split systems.
    Issue 2: DOE requests comment on its proposals in Appendix D1, 
section 429.43, and section 429.134 regarding specific components.
    Issue 3: DOE requests comment on its proposed definition for 
``Critical Parameter(s)'', which specifies the three parameters that 
can be manually controlled in testing per Section 5.1.2.1 of AHRI 1230-
2021--compressor speed(s), outdoor fan speed(s), and outdoor variable 
valve position(s).
    Issue 4: DOE seeks comment on its proposal for adding provisions at 
10 CFR 429.134(s)(3)(ii) to clarify the language in Sections C6.1.2 and 
C6.1.3 of AHRI 1230-2021 for validating critical parameters during a 
CVP, particularly pertaining to the duration of the measurement period 
used for validating critical parameters.
    Issue 5: DOE seeks comment on its proposal to specify at 10 CFR 
429.134(s)(3)(iii)(B) how, in the event of a CVP that has invalidated 
the critical parameter settings, alternate critical parameters would be 
determined to use as initial control inputs during the corresponding 
IEER full- or part-load cooling test. DOE requests feedback on the 
proposed method for selecting a measurement period on the basis of 
minimized average RSS points total, and also on its proposal for using 
an average of critical parameter measurements over the selected 
measurement period to calculate alternate critical parameters. DOE will 
further consider any alternate approaches suggested by comments in 
developing any final rule.
    Issue 6: DOE requests comment on its proposal to incorporate the 
CVP into its product-specific enforcement provisions for VRF multi-
split systems at 10 CFR 429.134(s) instead of the test procedure for 
VRF multi-split systems in the proposed appendix D1.
    Issue 7: DOE requests comment on its proposed approach for 
conducting the CVP during enforcement testing. Specifically, DOE 
requests comment on the proposal that DOE would conduct the CVP for a 
single system during enforcement testing in order to validate the 
certified critical parameters. If commenters believe conducting the CVP 
on a single system as part of enforcement testing is insufficient, DOE 
requests test data demonstrating any issues with repeatability and 
reproducibility of the CVP that would indicate that the 70-point budget 
for critical parameter variation included in the industry consensus 
test procedure AHRI 1230-2021 is insufficient.
    Issue 8: DOE seeks comment on its proposed provisions (to clarify 
similar provisions in AHRI 1230-2021) in section 4 of the proposed 
appendix D1 to subpart F of part 431 that specify allowable adjustments 
to critical parameters for IEER tests. Specifically, DOE requests 
feedback on its proposal to specify, for IEER tests for which the 
tested capacity is above the target capacity, calculation of normalized 
critical parameter variation during the adjustment process (similar to 
the calculation specified for the CVP in Section C4.4.2.3 of AHRI 1230-
2021).
    Issue 9: DOE seeks comment on the proposed provisions at Sec.  
429.134(s)(3)(iii)(B)(3) regarding allowable adjustment (to meet 
tolerances for capacity and SHR limits for an IEER test) of alternate 
critical parameter values determined by DOE in the event of a CVP that 
has invalidated the critical parameter settings.
    Issue 10: DOE requests comment on its proposals for determining 
represented values for VRF multi-split system basic models with 
different indoor unit combinations. In particular, DOE seeks feedback 
on its proposal to allow for optional mixed representations of any two 
required representations (i.e., ducted, non-ducted, and/or SDHV) for a 
basic model by calculating the mean of the two required 
representations.
    Issue 11: DOE requests comment on its proposal regarding 
representations for VRF multi-split system basic models approved for 
use with multiple refrigerants.
    Issue 12: DOE requests comment on its proposed certification 
reporting requirements for VRF multi-split systems.
    Issue 13: DOE requests comment on its proposed STI reporting 
requirements for VRF multi-split systems.
    Issue 14: DOE requests comment on its proposal to amend its 
requirements for AEDM validation for VRF multi-split systems.
    Issue 15: DOE seeks comment on its proposal to require a means of 
control to be provided by the manufacturer for assessment and 
enforcement testing.
    Issue 16: DOE seeks comment on its proposal to establish in 10 CFR 
429.134(s)(2) provisions regarding allowable manufacturer involvement 
during assessment and enforcement testing, which are consistent with 
AHRI 1230-2021. DOE also seeks comment on its proposal for allowable 
manufacturer involvement during the CVP.
    Issue 17: DOE requests comment on its proposed approaches for 
certification and for enforcement testing in the event that a VRF 
multi-split system has invalid certified operational settings for 
critical parameter values.
    Issue 18: DOE requests comment on its proposed enforcement sampling 
plan for VRF multi-split systems.
    Issue 19: DOE requests comment on its understanding of the impact 
of the test procedure proposals in this NOPR, specifically DOE's 
initial conclusion that the proposed DOE test procedure amendments, if 
finalized, would not increase testing burden on VRF multi-split system 
manufacturers, compared to current industry practice as indicated by 
AHRI 1230-2021.
    Issue 20: DOE requests comment on its assessment that there are no 
small businesses that are OEMs of VRF multi-split systems.
    Issue 21: DOE requests comment on its conclusion that the proposed 
rule would not have significant impacts on a substantial number of 
small manufacturers.
    Issue 22: DOE invites public comment on: (1) Whether the proposed 
information collection requirements are necessary for the performance 
of DOE's functions, including whether the information will have 
practical utility; (2) the accuracy of DOE's estimates of the burden of 
the proposed information collection requirements; (3) ways to enhance 
the quality, utility, and clarity of the information to be collected; 
and (4) ways to minimize the burden of the information collection 
requirements on respondents.

VI. Approval of the Office of the Secretary

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

List of Subjects

10 CFR Part 429

    Administrative practice and procedure, Confidential business

[[Page 70676]]

information, Energy conservation, Household appliances, Imports, 
Incorporation by reference, Intergovernmental relations, Reporting and 
recordkeeping requirements, Small businesses.

10 CFR Part 431

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

Signing Authority

    This document of the Department of Energy was signed on November 
29, 2021, by Kelly J. Speakes-Backman, Principal Deputy Assistant 
Secretary for Energy Efficiency and Renewable Energy, pursuant to 
delegated authority from the Secretary of Energy. That document with 
the original signature and date is maintained by DOE. For 
administrative purposes only, and in compliance with requirements of 
the Office of the Federal Register, the undersigned DOE Federal 
Register Liaison Officer has been authorized to sign and submit the 
document in electronic format for publication, as an official document 
of the Department of Energy. This administrative process in no way 
alters the legal effect of this document upon publication in the 
Federal Register.

    Signed in Washington, DC, on November 30, 2021.
Treena V. Garrett,
Federal Register Liaison Officer, U.S. Department of Energy.

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

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

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

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

0
2. Amend Sec.  429.4 by:
0
a. Revising paragraph (a); and
0
b. Redesignating paragraph (c)(2) as paragraph (c)(3) and adding new 
paragraph (c)(2).
    The revision and addition read as follows.


Sec.  429.4  Materials incorporated by reference.

    (a) Certain material is incorporated by reference into this subpart 
with the approval of the Director of the Federal Register in accordance 
with 5 U.S.C. 552(a) and 1 CFR part 51. To enforce any edition other 
than that specified in this section, DOE must publish a document in the 
Federal Register and the material must be available to the public. All 
approved material is available for inspection at the U.S. Department of 
Energy, Office of Energy Efficiency and Renewable Energy, [Building 
Technologies Program], Sixth Floor, 950 L'Enfant Plaza SW, Washington, 
DC 20024, (202)-586-9127, [email protected], https://www.energy.gov/eere/buildings/building-technologies-office, and may be obtained from 
the other sources in this section. It is also available for inspection 
at the National Archives and Records Administration (NARA). For 
information on the availability of this material at NARA, email: 
[email protected], or go to: www.archives.gov/federal-register/cfr/ibr-locations.html.
* * * * *
    (c) * * *
    (2) AHRI Standard 1230-2021, (``AHRI 1230-2021''), 2021 Standard 
for Performance Rating of Variable Refrigerant Flow (VRF) Multi-Split 
Air-Conditioning and Heat Pump Equipment, IBR approved for Sec. Sec.  
429.43 and 429.134.
* * * * *
0
3. Amend Sec.  429.43 by:
0
a. Revising the introductory text of paragraphs (a), (a)(1)(ii)(A), and 
(a)(1)(ii)(B);
0
b. Adding paragraphs (a)(3) through (5);
0
c. Revising paragraphs (b)(2)(xi) and (xii);
0
d. Removing paragraph (b)(2)(xiii);
0
e. Redesignating paragraphs (b)(2)(xiv) and (xv) as (b)(2)(xiii) and 
(xiv), respectively;
0
f. Revising paragraphs (b)(4)(vii) and (viii);
0
g. Removing paragraph (b)(4)(ix);
0
h. Redesignating paragraphs (b)(4)(x) through (b)(4)(xiv) as (b)(4)(ix) 
through (b)(4)(xiii), respectively;
    and
0
i. Adding paragraph (b)(5).
    The revisions and additions read as follows.


Sec.  429.43  Commercial heating, ventilating, air conditioning (HVAC) 
equipment.

    (a) Determination of represented values. Manufacturers must 
determine the represented values, which include the certified ratings, 
for each basic model of commercial HVAC equipment either by testing, in 
conjunction with the applicable sampling provisions, or by applying an 
AEDM.
    (1) * * *
    (ii) * * *
    (A) Any represented value of energy consumption or other measure of 
energy use of a basic model, or of a tested combination for variable 
refrigerant flow multi-split air conditioners and heat pumps certified 
to standards in terms of IEER as provided at paragraph (a)(3)(iv)(B) of 
this section, for which consumers would favor lower values shall be 
greater than or equal to the higher of:
* * * * *
    (B) Any represented value of energy efficiency or other measure of 
energy consumption of a basic model, or of a tested combination for 
variable refrigerant flow multi-split air conditioners and heat pumps 
certified to standards in terms of IEER as provided at paragraph 
(a)(3)(iv)(B) of this section, for which consumers would favor higher 
values shall be less than or equal to the lower of:
* * * * *
    (3) Product-specific provisions for determination of represented 
values.
    (i)--(iii) [Reserved]
    (iv) Variable refrigerant flow multi-split air conditioners and 
heat pumps (other than air-cooled with cooling capacity less than 
65,000 btu/h). When certifying to standards in terms of IEER, the 
following provisions apply.
    (A) If a basic model is distributed in commerce and approved for 
use with multiple refrigerants, a manufacturer must determine all 
represented values for that basic model (for example, IEER, COP, 
cooling capacity, and heating capacity) based on the refrigerant that 
results in the lowest cooling efficiency. A refrigerant is considered 
approved for use if it is listed on the nameplate of the outdoor unit. 
Per the definition of basic model in 10 CFR 431.92, use of a 
refrigerant that requires different hardware (i.e., compressors, heat 
exchangers, or air moving systems that are not the same or comparably 
performing), would represent a different basic model, and separate 
representations would be required for each basic model.
    (B) Represented values for different indoor unit combinations must 
be determined per the following provisions.
    (1) If a basic model includes only one type of indoor unit 
combination (i.e., ducted, non-ducted, or SDHV), a manufacturer must 
determine the represented values for that basic model in accordance 
with the sampling plan

[[Page 70677]]

set forth in Sec.  429.11 and paragraph (a)(1) of this section if the 
represented values are determined through testing, or in accordance 
with the provisions for applying an AEDM set forth in paragraph (a)(2) 
of this section and Sec.  429.70.
    (2) If a basic model includes more than one type of indoor unit 
combination (i.e., ducted, non-ducted, and/or SDHV), a manufacturer 
must determine separate represented values for each type of indoor unit 
combination. If the represented values are determined through testing, 
a manufacturer must test, at a minimum, a single tested combination for 
each type of indoor unit combination included in that basic model. A 
manufacturer may alternatively determine separate represented values 
through application of an AEDM as set forth in paragraph (a)(2) of this 
section and Sec.  429.70. A manufacturer may also determine optional 
``mixed'' representations by calculating the mean value across any two 
required representations described in this paragraph (i.e., a 
representation for ``mixed ducted/non-ducted'' would be determined by 
averaging the ducted representation and the non-ducted representation, 
a representation for ``mixed ducted/SDHV'' would be determined by 
averaging the ducted representation and the SDHV representation, and a 
representation for ``mixed non-ducted/SDHV'' would be determined by 
averaging the non-ducted representation and the SDHV representation).
    (4) Determination of represented values for individual models with 
specific components for VRF multi-split systems.
    (i) If a manufacturer distributes in commerce indoor unit model(s) 
in a tested combination within a basic model with one of the components 
listed in the following table, determination of represented values is 
dependent on the selected grouping of individual indoor unit models 
into a tested combination within a basic model, as indicated in 
paragraphs (a)(4)(ii) through (v) of this section. For the purposes of 
this paragraph, ``otherwise identical'' means differing only in the 
presence of specific components listed in table 1 to paragraph 
(a)(4)(i).

                     Table 1 to Paragraph (a)(4)(i)
------------------------------------------------------------------------
              Component                           Description
------------------------------------------------------------------------
Air economizers......................  An automatic system that enables
                                        a cooling system to supply and
                                        use outdoor air to reduce or
                                        eliminate the need for
                                        mechanical cooling during mild
                                        or cold weather.
Dehumidification Components..........  An assembly that reduced the
                                        moisture content of the supply
                                        air through moisture transfer
                                        with solid or liquid desiccants.
------------------------------------------------------------------------

    (ii) If the indoor unit model(s) in a tested combination within a 
basic model include only individual indoor unit models distributed in 
commerce without a specific component listed in paragraph (a)(4)(i) of 
this section, the manufacturer must determine represented values for 
the tested combination based on performance of individual indoor unit 
models distributed in commerce without the component.
    (iii) If the indoor unit model(s) in a tested combination within a 
basic model include only individual indoor unit models distributed in 
commerce with a specific component listed in paragraph (a)(4)(i) of 
this section, the manufacturer must determine represented values for 
the tested combination based on performance of individual indoor unit 
models with the component present (and consistent with any component-
specific test provisions specified in section 6 of appendix D1 to 
subpart F of part 431).
    (iv) If the indoor unit model(s) in a tested combination within a 
basic model--
    (A) Include both individual indoor unit models distributed in 
commerce with a specific component listed in paragraph (a)(4)(i) of 
this section and individual indoor unit models distributed in commerce 
without that specific component, and
    (B) None of the individual indoor unit models distributed in 
commerce without the specific component are otherwise identical to any 
individual indoor unit model distributed in commerce with that specific 
component, the manufacturer must consider the performance of individual 
indoor unit models with the component present when determining 
represented values for the tested combination within a basic model (and 
consistent with any component-specific test provisions specified in 
section 6 of appendix D1 to subpart F of part 431).
    (v) If the indoor unit model(s) in a tested combination within a 
basic model--
    (A) Include both individual indoor unit models distributed in 
commerce with a specific component listed in paragraph (a)(4)(i) of 
this section and individual indoor unit models distributed in commerce 
without that specific component, and
    (B) At least one of the individual indoor unit models distributed 
in commerce without the specific component is otherwise identical to 
any given individual indoor unit model distributed in commerce with the 
specific component, the manufacturer may determine represented values 
for the tested combination within a basic model either:
    (1) Based on performance of individual indoor unit models 
distributed in commerce without the specific component, or
    (2) Based on performance of individual indoor unit models with the 
specific component present (and consistent with any component-specific 
test provisions specified in section 6 of appendix D1 to subpart F of 
part 431).
    (vi) In any of the cases specified in paragraphs (a)(4)(ii) through 
(v) of this section, the represented values for a tested combination 
within a basic model must be determined in accordance with paragraph 
(a)(3) of this section, through either testing or an AEDM.
    (5) Heat Recovery. For basic models of VRF multi-split systems 
distributed in commerce with heat recovery components, the manufacturer 
must determine represented values for the basic model based on 
performance of an individual model distributed in commerce with heat 
recovery components.
    (b) * * *
    (2) * * *
    (xi) Variable refrigerant flow multi-split air-cooled air 
conditioners (except those with rated cooling capacity less than 65,000 
Btu/h):
    (A) When certifying compliance with an EER standard: The energy 
efficiency ratio (EER in British thermal units per Watt-hour (Btu/Wh)), 
rated cooling capacity in British thermal units per hour (Btu/h), and 
the type(s) of heating

[[Page 70678]]

used by the basic model (e.g., electric, gas, hydronic, none).
    (B) When certifying compliance with an IEER standard, the following 
must be certified for each tested combination as required under 
paragraph (a)(3)(iv)(B) of this section: The integrated energy 
efficiency ratio (IEER) in British thermal units per Watt-hour (Btu/
Wh)); the rated cooling capacity in British thermal units per hour 
(Btu/h); whether the represented values are for a non-ducted, ducted, 
or SDHV tested combination, or for a mixed representation of any two of 
the tested combinations; and the outdoor unit(s) and indoor units 
identified in the tested combination. The following must be certified 
for each basic model: The type(s) of heating used (i.e., electric, gas, 
hydronic, none); and the refrigerant used to determine the represented 
values.
    (xii) Variable refrigerant flow multi-split heat pumps (other than 
air-cooled with rated cooling capacity less than 65,000 btu/h):
    (A) When certifying compliance with an EER standard: The energy 
efficiency ratio (EER in British thermal units per Watt-hour (Btu/Wh)), 
the coefficient of performance (COP), rated cooling capacity in British 
thermal units per hour (Btu/h), and the type(s) of heating used by the 
basic model (e.g., electric, gas, hydronic, none).
    (B) When certifying compliance with an IEER standard, the following 
must be certified for each tested combination as required under 
paragraph (a)(3)(iv)(B) of this section: The integrated energy 
efficiency ratio (IEER) in British thermal units per Watt-hour (Btu/
Wh)); the coefficient of performance (COP); the rated cooling capacity 
in British thermal units per hour (Btu/h); the rated heating capacity 
(Btu/h); whether the represented values are for a non-ducted, ducted, 
or SDHV tested combination, or for a mixed representation of any two of 
the tested combinations; and the outdoor unit(s) and indoor units 
identified in the tested combination. The following must be certified 
for each basic model: the type(s) of heating used (i.e., electric, gas, 
hydronic, none); and the refrigerant used to determine the represented 
values.
* * * * *
    (4) * * *
    (vii) Variable refrigerant flow multi-split air-cooled air 
conditioners (except those with rated cooling capacity less than 65,000 
Btu/h):
    (A) When certifying compliance with an EER standard: The nominal 
cooling capacity in British thermal units per hour (Btu/h); outdoor 
unit(s) and indoor units identified in the tested combination; 
components needed for heat recovery, if applicable; rated airflow in 
standard cubic feet per minute (scfm) for each indoor unit; rated 
static pressure in inches of water; compressor frequency set points; 
required dip switch/control settings for step or variable components; a 
statement whether the model will operate at test conditions without 
manufacturer programming; any additional testing instructions if 
applicable; if a variety of motors/drive kits are offered for sale as 
options in the basic model to account for varying installation 
requirements, the model number and specifications of the motor (to 
include efficiency, horsepower, open/closed, and number of poles) and 
the drive kit, including settings, associated with that specific motor 
that were used to determine the certified rating; and which, if any, 
special features were included in rating the basic model. Additionally, 
upon DOE request, the manufacturer must provide a layout of the system 
set-up for testing including charging instructions consistent with the 
installation manual.
    (B) When certifying compliance with an IEER standard (for 
requirements in this list pertaining to or affected by indoor units, 
the requirements must be certified for each tested combination as 
required under paragraph (a)(3)(iv)(B) of this section): The nominal 
cooling capacity in British thermal units per hour (Btu/h) for each 
indoor and outdoor unit; identification of the indoor units to be 
thermally active for each IEER test point; the rated indoor airflow for 
the full-load cooling and all part-load cooling tests (for each indoor 
unit) in standard cubic feet per minute (scfm); the indoor airflow-
control setting to be used in the full-load cooling test (for each 
indoor unit); system start-up or initialization procedures, including 
conditions and duration; compressor break-in period duration; the 
frequency of oil recovery cycles; operational settings for all critical 
parameters to be controlled at each of the four IEER cooling test 
conditions; required dip switch/control settings; identification of any 
system control device required for testing; a hierarchy of instructions 
for adjustment of critical parameters to reduce cooling capacity during 
IEER cooling tests (to be used if, using initial critical parameter 
settings, the measured cooling capacity is more than 3 percent above 
the target cooling capacity); any additional testing instructions if 
applicable; and if a variety of motors/drive kits are offered for sale 
as options in the basic model to account for varying installation 
requirements, the model number and specifications of the motor (to 
include efficiency, horsepower, open/closed, and number of poles) and 
the drive kit, including settings, associated with that specific motor 
that were used to determine the certified rating. Instructions for 
conducting a controls verification procedure (as described in Appendix 
C of AHRI 1230-2021, (incorporated by reference, see Sec.  429.4)) at 
each of the four IEER cooling test conditions must also be provided, 
including: The required thermostat setpoints to ensure control for 80 
[deg]F dry-bulb temperature when accounting for set point bias, the 
starting indoor dry-bulb temperature, and the indoor dry-bulb 
temperature ramp rate (R2). Additionally, the manufacturer must provide 
a layout of the system set-up for testing (including a piping diagram, 
a power wiring diagram, a control wiring diagram, and identification of 
the location of the component(s) corresponding to each critical 
parameter to be controlled), setup instructions for indoor units and 
outdoor units, and charging instructions consistent with the 
installation manual. Also, the manufacturer must certify for which, if 
any, specific components (as listed in paragraph (a)(4)(i) of this 
section) the following provisions are applicable:
    (1) The indoor unit model(s) in a tested combination within a basic 
model include both individual indoor unit models distributed in 
commerce with the specific component and individual indoor unit models 
distributed in commerce without the specific component;
    (2) At least one of the individual indoor unit models distributed 
in commerce without the specific component is otherwise identical to 
any given individual indoor unit model distributed in commerce with the 
specific component; and
    (3) Represented values for the tested combination are based on 
performance of individual indoor unit models distributed in commerce 
without the specific component.
    (viii) Variable refrigerant flow multi-split heat pumps (other than 
air-cooled with rated cooling capacity less than 65,000 btu/h):
    (A) When certifying compliance with an EER standard: The nominal 
cooling capacity in British thermal units per hour (Btu/h); rated 
heating capacity in British thermal units per hour (Btu/h); outdoor 
unit(s) and indoor units identified in the tested combination; 
components needed for heat recovery, if applicable; rated airflow in 
standard cubic feet per minute (scfm) for each indoor unit; water flow 
rate in gallons

[[Page 70679]]

per minute (gpm) for water-cooled units only; rated static pressure in 
inches of water; compressor frequency set points; required dip switch/
control settings for step or variable components; a statement whether 
the model will operate at test conditions without manufacturer 
programming; any additional testing instructions if applicable; if a 
variety of motors/drive kits are offered for sale as options in the 
basic model to account for varying installation requirements, the model 
number and specifications of the motor (to include efficiency, 
horsepower, open/closed, and number of poles) and the drive kit, 
including settings, associated with that specific motor that were used 
to determine the certified rating; and which, if any, special features 
were included in rating the basic model. Additionally, upon DOE 
request, the manufacturer must provide a layout of the system set-up 
for testing including charging instructions consistent with the 
installation manual.
    (B) When certifying compliance with an IEER standard (for 
requirements in this list pertaining to or affected by indoor units, 
the requirements must be certified for each tested combination as 
required under paragraph (a)(3)(iv)(B) of this section): The nominal 
cooling capacity in British thermal units per hour (Btu/h) for each 
indoor and outdoor unit; the nominal heating capacity (Btu/h) for each 
indoor and outdoor unit; components needed for heat recovery, if 
applicable; identification of the indoor units to be thermally active 
for each IEER test point; the rated indoor airflow for the full-load 
cooling, full-load heating, and all part-load cooling tests (for each 
indoor unit) in standard cubic feet per minute (scfm); the indoor 
airflow-control setting to be used in the full-load cooling test (for 
each indoor unit); the airflow-control setting to be used in the full-
load heating test (for each indoor unit); for water-cooled units--the 
rated water flow rate in gallons per minute (gpm); system start-up or 
initialization procedures, including conditions and duration; 
compressor break-in period duration; the frequency of oil-recovery 
cycles; operational settings for all critical parameters to be 
controlled at each of the four IEER cooling test conditions; 
operational settings for all critical parameters to be controlled for 
the heating test; required dip switch/control settings; identification 
of any system control device required for testing; a hierarchy of 
instructions for adjustment of critical parameters to reduce cooling 
capacity during IEER cooling tests (to be used if, using initial 
critical parameter settings, the measured cooling capacity is more than 
3 percent above the target cooling capacity); any additional testing 
instructions if applicable; and if a variety of motors/drive kits are 
offered for sale as options in the basic model to account for varying 
installation requirements, the model number and specifications of the 
motor (to include efficiency, horsepower, open/closed, and number of 
poles) and the drive kit, including settings, associated with that 
specific motor that were used to determine the certified rating. 
Instructions for conducting a controls verification procedure (as 
described in Appendix C of AHRI 1230-2021) at each of the four IEER 
cooling test conditions must also be provided, including the required 
thermostat setpoints to ensure control for 80 [deg]F dry-bulb 
temperature when accounting for set point bias, the starting indoor 
dry-bulb temperature, and the indoor dry-bulb temperature ramp rate 
(R2). Additionally, the manufacturer must provide a layout of the 
system set-up for testing (including a piping diagram, a power wiring 
diagram, a control wiring diagram, and identification of the location 
of the component(s) corresponding to each critical parameter to be 
adjusted), setup instructions for indoor units and outdoor units, and 
charging instructions consistent with the installation manual. Also, 
the manufacturer must certify for which, if any, specific components 
(as listed in paragraph (a)(4)(i) of this section) the following 
provisions are applicable:
    (1) The indoor unit model(s) in a tested combination within a basic 
model include both individual indoor unit models distributed in 
commerce with the specific component and individual indoor unit models 
distributed in commerce without the specific component;
    (2) At least one of the individual indoor unit models distributed 
in commerce without the specific component is otherwise identical to 
any given individual indoor unit model distributed in commerce with the 
specific component; and
    (3) Represented values for the tested combination are based on 
performance of individual indoor unit models distributed in commerce 
without the specific component.
* * * * *
    (5) For variable refrigerant flow multi-split air conditioners and 
heat pumps (other than air-cooled with rated cooling capacity less than 
65,000 btu/h), if a manufacturer has knowledge that any of its 
certified operational settings for critical parameters to be controlled 
during IEER tests (per paragraphs (b)(4)(vii)(B) or (b)(4)(viii)(B) of 
this section) are invalid according to the results of a controls 
verification procedure appropriately conducted according to Sec.  
429.134(s)(3), then the manufacturer must re-certify valid operational 
settings for critical parameters for all affected basic models, and re-
rate and re-certify all affected basic models.
* * * * *
0
4. Amend Sec.  429.70 by revising paragraph (c)(2)(i) to read as 
follows:


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

* * * * *
    (c) * * *
    (2) * * *
    (i) The manufacturer must select at least the minimum number of 
basic models for each validation class specified in paragraph 
(c)(2)(iv) of this section to which the particular AEDM applies. Using 
the AEDM, calculate the energy use or efficiency for each of the 
selected basic models.
    (A) Except for variable refrigerant flow multi-split air 
conditioners and heat pumps (other than air-cooled with rated cooling 
capacity less than 65,000 btu/h) when certifying to standards in terms 
of IEER, test a single unit of each selected basic model in accordance 
with paragraph (c)(2)(iii) of this section. Compare the results from 
the single unit test and the AEDM energy use or efficiency output 
according to paragraph (c)(2)(ii) of this section. The manufacturer is 
responsible for ensuring the accuracy and reliability of the AEDM.
    (B) For variable refrigerant flow multi-split air conditioners and 
heat pumps (other than air-cooled with rated cooling capacity less than 
65,000 btu/h) when certifying to standards in terms of IEER, the 
following provisions apply.
    (1) If a manufacturer makes representations for a single type of 
indoor unit combination (i.e., only ducted, non-ducted, or SDHV indoor 
unit combinations) across all the basic models for which an AEDM 
applies, the manufacturer must test at least a single tested 
combination of that type of indoor unit combination for each selected 
basic model in accordance with paragraph (c)(2)(iii) of this section.
    (2) If a manufacturer makes representations for two types of indoor 
unit combinations (i.e., ducted, non-ducted, and/or SDHV) within or 
across all the basic models for which the AEDM applies, the 
manufacturer must test at least a single tested combination

[[Page 70680]]

of a selected basic model as the first of those two types of indoor 
unit combination, and at least a single tested combination of a 
different selected basic model as the second of those two types of 
indoor unit combination, each in accordance with paragraph (c)(2)(iii) 
of this section.
    (3) If a manufacturer makes representations for all three types of 
indoor unit combinations (i.e., ducted, non-ducted, and SDHV) within or 
across basic models for which the AEDM applies, the manufacturer must 
test at least a single tested combination of a selected basic model as 
a non-ducted tested combination and a single tested combination of a 
different selected basic model as a ducted tested combination, each in 
accordance with paragraph (c)(2)(iii) of this section.
    (4) In all cases, compare the results from each tested basic model 
and the AEDM energy use or efficiency output according to paragraph 
(c)(2)(ii) of this section. The manufacturer is responsible for 
ensuring the accuracy and reliability of the AEDM.
* * * * *
0
5. Section 429.104 is revised to read as follows:


Sec.  429.104  Assessment testing.

    (a) DOE may, at any time, test a basic model to assess whether the 
basic model is in compliance with the applicable energy conservation 
standard(s).
    (b) For variable refrigerant flow multi-split air conditioners and 
heat pumps (other than air-cooled with rated cooling capacity less than 
65,000 btu/h) DOE may require that the manufacturer of a basic model 
ship or cause to be shipped from a retailer or distributor at its 
expense the means of control associated with the basic model, if 
applicable.
0
6. Amend Sec.  429.110 by:
0
a. Redesignating paragraphs (a)(2) and (3) as paragraphs (a)(3) and 
(4), respectively;
0
b. Adding new paragraph (a)(2);
0
c. Revising paragraph (b)(1)(iv);
0
d. Revising paragraph (e)(2);
0
e. Redesignating paragraphs (e)(3) through (9) as (e)(4) through (10), 
respectively;
0
f. Adding new paragraph (e)(3);
0
g. In newly designated paragraph (e)(4), remove the words ``(e)(1) or 
(2) of this section'' and add in its place the words, ``(e)(1), (2) or 
(3) of this section'';
0
h. In newly designated paragraph (e)(8), remove the words ``(e)(1) 
through (6)'' and add in its place the words ``(e)(1) through (7)''; 
and
0
i. In newly designated paragraph (e)(9), remove the words ``paragraph 
(e)(7)'' and ``paragraphs (e)(1) through (6)'' and add in their place 
the words ``paragraph (e)(8)'' and ``paragraphs (e)(1) through (7)'', 
respectively;
    The additions and revisions read as follows.


Sec.  429.110  Enforcement testing.

    (a) * * *
    (2) For variable refrigerant flow multi-split air conditioners and 
heat pumps (other than air-cooled with rated cooling capacity less than 
65,000 Btu/h) determining compliance with an energy conservation 
standard based on IEER, DOE may test for enforcement if DOE has reason 
to believe that a basic model is not in compliance, has invalid 
certified operational settings for critical parameter values, or has an 
otherwise invalid certified rating.
* * * * *
    (b) * * *
    (1) * * *
    (iv) DOE may require in the test notice that the manufacturer of a 
basic model ship or cause to be shipped from a retailer or distributor 
at its expense the requested number of units of a basic model specified 
in such test notice to the testing laboratory specified in the test 
notice. The manufacturer shall ship the specified initial test unit(s) 
of the basic model and to the testing laboratory within 5 working days 
from the time unit(s) are selected. For variable refrigerant flow 
multi-split air conditioners and heat pumps (other than air-cooled with 
rated cooling capacity less than 65,000 btu/h) the manufacturer shall 
also ship any means of control necessary for conducting testing in 
accordance with appendix D1 to part 431 of this subchapter. The 
manufacturer shall ship the means of control, if applicable, with the 
system(s) selected for testing.
* * * * *
    (e) * * *
    (2) For automatic commercial ice makers; commercial refrigerators, 
freezers, and refrigerator-freezers; refrigerated bottled or canned 
vending machines; commercial air conditioners and heat pumps except 
variable refrigerant flow multi-split air conditioners and heat pumps 
(other than air-cooled with rated cooling capacity less than 65,000 
btu/h); commercial packaged boilers; commercial warm air furnaces; 
commercial water heating equipment; and walk-in cooler and walk-in 
freezer refrigeration systems, DOE will use an initial sample size of 
not more than four units and follow the sampling plans in appendix B of 
this subpart (Sampling Plan for Enforcement Testing of Covered 
Equipment and Certain Low-Volume Covered Products).
    (3) For variable refrigerant flow multi-split air conditioners and 
heat pumps (other than air-cooled with rated cooling capacity less than 
65,000 btu/h).
    (i) For determining compliance with an energy conservation standard 
based on EER, DOE will use an initial sample size of not more than four 
units and follow the sampling plans in appendix B of this subpart 
(Sampling Plan for Enforcement Testing of Covered Equipment and Certain 
Low-Volume Covered Products).
    (ii) For determining compliance with an energy conservation 
standard based on IEER, DOE will use an initial sample size of two 
units and follow the sampling plans in appendix B of this subpart 
(Sampling Plan for Enforcement Testing of Covered Equipment and Certain 
Low-Volume Covered Products).
* * * * *
0
7. Amend Sec.  429.134 by adding paragraph (s) to read as follows:


Sec.  429.134  Product-specific enforcement provisions.

* * * * *
    (s) Variable refrigerant flow multi-split air conditioners and heat 
pumps (other than air-cooled with rated cooling capacity less than 
65,000 btu/h). The following provisions apply for assessment and 
enforcement testing of models subject to standards in terms of IEER:
    (1) Specific Components. If the indoor unit model(s) in a tested 
combination within a basic model include individual indoor unit models 
distributed in commerce with any of the specific components listed at 
Sec.  429.43(a)(4)(i), the following provisions apply. For the purposes 
of this paragraph, ``otherwise identical'' means differing only in the 
presence of specific components listed at Sec.  429.43(a)(4)(i).
    (i) If the manufacturer does not certify in accordance with Sec.  
429.43(b)(4) that--
    (A) Indoor unit model(s) in a tested combination within a basic 
model include both individual indoor unit models distributed in 
commerce with a specific component and otherwise identical individual 
indoor unit models distributed in commerce without the specific 
component, and
    (B) Represented values for the tested combination are based on 
performance of individual indoor unit models distributed in commerce 
without the specific component, DOE may test the tested combination 
with individual indoor unit models with the component present (and 
consistent with any component-specific test provisions specified in 
section 6 of appendix D1 to subpart F of part 431).

[[Page 70681]]

    (ii) If the manufacturer certifies in accordance with Sec.  
429.43(b)(4) that--
    (A) Indoor unit model(s) in a tested combination within a basic 
model include both individual indoor unit models distributed in 
commerce with a specific component and otherwise identical individual 
indoor unit models distributed in commerce without the specific 
component, and
    (B) Represented values for the tested combination are based on 
performance of individual indoor unit models distributed in commerce 
without the specific component, DOE will test the tested combination 
with otherwise identical indoor unit model(s) within the tested 
combination within a basic model that do not include the component, 
except in either of the following situations. In either of the 
following situations, DOE may test the tested combination with 
individual indoor unit models with the specific component present (and 
consistent with any component-specific test provisions specified in 
section 6 of appendix D1 to subpart F of part 431).
    (1) DOE is not able, through documented reasonable effort, to 
obtain individual indoor unit models for testing that do not include 
the component.
    (2) DOE becomes aware that the manufacturer's certification in 
accordance with Sec.  429.43(b)(4) regarding specific components is 
invalid.
    (2) Manufacturer involvement in assessment or enforcement testing. 
A manufacturer's representative will be allowed to support 
commissioning and witness assessment and/or enforcement testing for 
variable refrigerant flow multi-split air conditioners and heat pumps, 
including during the controls verification procedures (CVPs), specified 
in paragraph (s)(3) of this section, with allowance for additional 
involvement as described in the following provisions.
    (i) Manufacturer involvement in CVP--Control settings must be set 
by a member of the third-party laboratory and per the provisions in 
section 5.1 of appendix D1 to subpart F of part 431. Critical 
parameters must operate automatically from the system controls and must 
not be manually controlled or adjusted at any point during the CVP. The 
manufacturer's representative must not make any adjustments to the VRF 
multi-split system for a CVP.
    (ii) Manufacturer involvement in heating tests and IEER cooling 
tests--All control settings other than critical parameters must be set 
by a member of the third-party laboratory, following the provisions of 
section 5.1 of appendix D1 to subpart F of part 431. Critical 
parameters may be manually controlled by a manufacturer's 
representative, including initial setting to the certified values and 
additional adjustments (as described in sections 5.1 and 5.2 of 
appendix D1 to subpart F of part 431, respectively). Setting and 
adjustment of critical parameters by a manufacturer's representative 
must be monitored by third-party laboratory personnel using a service 
tool. The manufacturer's representative must not make any other 
adjustments to the VRF multi-split system under test. If a 
manufacturer's representative is not present for testing, a member of 
the third-party laboratory must set and adjust critical parameters 
using the provided means of control described in Sec.  
429.110(b)(1)(iv) for enforcement testing and Sec.  429.104 for 
assessment testing.
    (3) Controls Verification Procedure (CVP). This procedure validates 
the certified values of critical parameters for which positions may be 
manually set during the full- and part-load IEER cooling test 
conditions specified at appendix D1 to subpart F of part 431. The CVP 
will only be conducted for a single system.
    (i) Conducting the CVP--The CVP will be conducted at all of the 
four IEER cooling test conditions as specified in appendix D1 to 
subpart F of part 431; the CVP is not applicable for any heating test 
conditions. The CVP will first be performed at the full-load cooling 
condition before being conducted at part-load cooling conditions and 
must be conducted per Appendix C of AHRI 1230-2021 (incorporated by 
reference, see Sec.  429.4).
    (ii) Validating Critical Parameters--At each load point, certified 
critical parameter values will be validated or invalidated according to 
Section C6 of AHRI 1230-2021 with the following amendments:
    (A) The duration of the period used for validating certified 
critical parameter values must be whichever of the following is longer: 
Three minutes, or the time period needed to obtain five sample readings 
while meeting the minimum data collection interval requirements of 
Table C2 of AHRI 1230-2021.
    (B) If at least one measurement period with duration identified in 
paragraph (s)(3)(ii)(A) of this section exists before tOFF 
that has an average root-sum-square (``RSS'') points total (as defined 
in Section 3.26 of AHRI 1230-2021) over the measurement period that is 
less than or equal to 70 points, the certified critical parameter 
values are valid.
    (C) If no measurement period with duration identified in paragraph 
(s)(3)(ii)(A) of this section exists before tOFF that has an 
average RSS points total over the measurement period that is less than 
or equal to 70 points, the certified critical parameter values are 
invalid.
    (iii) Determining critical parameters for use in steady-state IEER 
cooling tests--If, following a CVP, IEER testing is conducted per 
appendix D1 to subpart F of part 431, the following provisions apply:
    (A) Validated critical parameter settings. At each load point, if 
certified critical parameter values are found to be valid according to 
the results of the CVP, initially set critical parameters to their 
certified values for the IEER test at the corresponding full- or part-
load cooling condition. Perform additional adjustments to critical 
parameters as described in section 5.2 of appendix D1 to subpart F of 
part 431.
    (B) Invalidated critical parameter settings. At each load point, if 
certified critical parameter values are found to be invalid according 
to the results of the CVP, determine alternate critical parameter 
values for use in the corresponding IEER test (as specified in appendix 
D1 to subpart F of part 431). Determine alternate critical parameter 
values from the CVP results of the single system described in paragraph 
(s)(3) of this section as follows:
    (1) Select the CVP measurement period--this period must have 
duration determined per paragraph (s)(3)(ii)(A) of this section and 
must be the period where the RSS points total has a lower average value 
over the measurement period than over any other time period in the CVP 
of the same duration. If multiple periods exist with the same RSS 
points total, select the measurement period closest to but before the 
time that the first indoor unit switches to thermally inactive (denoted 
as ``toff'' in AHRI 1230-2021).
    (2) Determine alternate critical parameters--calculate the average 
position for each critical parameter during the measurement period 
selected in paragraph (s)(3)(iii)(B)(1) of this section. When initially 
setting critical parameters per section 5.1 of appendix D1 to subpart F 
of part 431, instead of using the certified critical parameter values, 
use the alternate critical parameter values as control inputs. The same 
initial alternate critical parameter values must be used for all 
systems in the assessment/enforcement sample (though critical parameter 
adjustments as needed to achieve target capacity or sensible heat ratio 
(SHR) limits are made independently for each tested system, per 
paragraph (s)(3)(iii)(B)(3) of this section.
    (3) For each system, determine whether critical parameter 
adjustments

[[Page 70682]]

are needed to achieve the target capacity or sensible heat ratio (SHR) 
limit for an IEER cooling test. Perform critical parameter adjustments 
independently on each system as described in section 5.2 of appendix D1 
to subpart F of part 431, with the following exceptions:
    (i) Replace all references to ``certified critical parameter 
values'' with ``alternate critical parameter values'' as determined in 
paragraph (s)(3)(iii)(B) of this section.
    (ii) Determine CPMax from a CVP conducted at full-load cooling 
conditions as the maximum value observed during the R2 period as 
described in Section C.4.4.2.3 of AHRI 1230-2021. If multiple 
components corresponding to a single parameter are present, determine 
CPMax at the point during the R2 period at which the average value 
across all components corresponding to that critical parameter is 
maximized.

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

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

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

0
9. Section 431.92 is amended by revising the definition of ``Integrated 
energy efficiency ratio, or IEER'' to read as follows:


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

* * * * *
    Integrated energy efficiency ratio, or IEER, means a weighted 
average calculation of mechanical cooling EERs determined for four load 
levels and corresponding rating conditions, expressed in Btu/watt-hour. 
IEER is measured per appendix A of this subpart for air-cooled small 
(>=65,000 Btu/h), large, and very large commercial package air 
conditioning and heating equipment and measured per appendix D1 of this 
subpart for variable refrigerant flow multi-split air conditioners and 
heat pumps (other than air-cooled with rated cooling capacity less than 
65,000 Btu/h).
* * * * *
0
10. Amend Sec.  431.95 by:
0
a. Revising paragraph (a);
0
b. Revising paragraph (b)(6);
0
c. Adding paragraph (b)(7); and
0
d. Revising paragraph (c)(2).
    The revisions and addition read as follows:


Sec.  431.95  Materials incorporated by reference.

    (a) Certain material is incorporated by reference into this subpart 
with the approval of the Director of the Federal Register in accordance 
with 5 U.S.C. 552(a) and 1 CFR part 51. To enforce any edition other 
than that specified in this section, DOE must publish a document in the 
Federal Register and the material must be available to the public. All 
approved material is available for inspection at the U.S. Department of 
Energy, Office of Energy Efficiency and Renewable Energy, Building 
Technologies Program, Sixth Floor, 950 L'Enfant Plaza SW, Washington, 
DC 20024, (202) 586-9127, [email protected], https://www.energy.gov/eere/buildings/building-technologies-office, and may be obtained from 
the other sources in this section. It is also available for inspection 
at the National Archives and Records Administration (NARA). For 
information on the availability of this material at NARA, email: 
[email protected], or go to: www.archives.gov/federal-register/cfr/ibr-locations.html.
    (b) * * *
    (6) ANSI/AHRI Standard 1230-2010, ``2010 Standard for Performance 
Rating of Variable Refrigerant Flow (VRF) Multi-Split Air-Conditioning 
and Heat Pump Equipment,'' approved August 2, 2010 and updated by 
addendum 1 in March 2011 (AHRI 1230-2010), IBR approved for Sec.  
431.96 and appendix D of this subpart.
    (7) AHRI Standard 1230-2021, ``Performance Rating of Variable 
Refrigerant Flow (VRF) Multi-Split Air-Conditioning and Heat Pump 
Equipment'', published in 2021 (AHRI 1230-2021), IBR approved for 
appendix D1 of this subpart.
    (c) * * *
    (2) ANSI/ASHRAE Standard 37-2009, (``ANSI/ASHRAE 37-2009''), 
``Methods of Testing for Rating Electrically Driven Unitary Air-
Conditioning and Heat Pump Equipment'', (including Errata Sheet issued 
October 3, 2016), ASHRAE approved June 24, 2009, IBR approved for Sec.  
431.96 and appendices A and D1 of this subpart.
* * * * *
0
11. Amend Sec.  431.96 by:
0
a. Revising paragraph (b)(1);
0
b. Redesignating table 1 to paragraph (b)(2) as table 1 to Sec.  
431.96; and
0
c. Revising newly redesignated table 1 to Sec.  431.96.
    The revisions read as follows:


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

* * * * *
    (b) Testing and calculations. (1) Determine the energy efficiency 
of each type of covered equipment by conducting the test procedure(s) 
listed in table 1 to this section along with any additional testing 
provisions set forth in paragraphs (c) through (g) of this section and 
appendices A through D1 of this subpart, that apply to the energy 
efficiency descriptor for that equipment, category, and cooling 
capacity. The omitted sections of the test procedures listed in table 1 
to this section must not be used. For equipment with multiple 
appendices listed in table 1 to this section, consult the notes at the 
beginning of those appendices to determine the applicable appendix to 
use for testing.
    (2) * * *

                                Table 1 to Sec.   431.96--Test Procedures for Commercial Air Conditioners and Heat Pumps
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                    Use tests,      Additional test procedure provisions
         Equipment type                 Category         Cooling capacity    Energy efficiency    conditions, and        as indicated in the listed
                                                                                descriptor       procedures \1\ in       paragraphs of this section
--------------------------------------------------------------------------------------------------------------------------------------------------------
Small Commercial Package Air-     Air-Cooled, 3-       <65,000 Btu/h......  SEER and HSPF.....  AHRI 210/240-2008   None.
 Conditioning and Heating          Phase, AC and HP.                                             (omit section
 Equipment.                                                                                      6.5).
                                  Air-Cooled AC and    >=65,000 Btu/h and   EER, IEER, and COP  Appendix A of this  None.
                                   HP.                  <135,000 Btu/h.                          subpart.
                                  Water-Cooled and     <65,000 Btu/h......  EER...............  AHRI 210/240-2008   Paragraphs (c) and (e).
                                   Evaporatively-                                                (omit section
                                   Cooled AC.                                                    6.5).

[[Page 70683]]

 
                                                       >=65,000 Btu/h and   EER...............  AHRI 340/360-2007   Paragraphs (c) and (e).
                                                        <135,000 Btu/h.                          (omit section
                                                                                                 6.3).
                                  Water-Source HP....  <135,000 Btu/h.....  EER and COP.......  ISO Standard 13256- Paragraph (e).
                                                                                                 1 (1998).
Large Commercial Package Air-     Air-Cooled AC and    >=135,000 Btu/h and  EER, IEER and COP.  Appendix A to this  None.
 Conditioning and Heating          HP.                  <240,000 Btu/h.                          subpart.
 Equipment.
                                  Water-Cooled and     >=135,000 Btu/h and  EER...............  AHRI 340/360-2007   Paragraphs (c) and (e).
                                   Evaporatively-       <240,000 Btu/h.                          (omit section
                                   Cooled AC.                                                    6.3).
Very Large Commercial Package     Air-Cooled AC and    >=240,000 Btu/h and  EER, IEER and COP.  Appendix A to this  None.
 Air-Conditioning and Heating      HP.                  <760,000 Btu/h.                          subpart.
 Equipment.
                                  Water-Cooled and     >=240,000 Btu/h and  EER...............  AHRI 340/360-2007   Paragraphs (c) and (e).
                                   Evaporatively-       <760,000 Btu/h.                          (omit section
                                   Cooled AC.                                                    6.3).
Packaged Terminal Air             AC and HP..........  <760,000 Btu/h.....  EER and COP.......  Paragraph (g) of    Paragraphs (c), (e), and (g).
 Conditioners and Heat Pumps.                                                                    this section.
Computer Room Air Conditioners..  AC.................  <65,000 Btu/h......  SCOP..............  ASHRAE 127-2007     Paragraphs (c) and (e).
                                                                                                 (omit section
                                                                                                 5.11).
                                                       >=65,000 Btu/h and   SCOP..............  ASHRAE 127-2007     Paragraphs (c) and (e).
                                                        <760,000 Btu/h.                          (omit section
                                                                                                 5.11).
Variable Refrigerant Flow Multi-  AC.................  <65,000 Btu/h (3-    SEER..............  ANSI/AHRI 1230-     Paragraphs (c), (d), (e), and (f).
 split Systems.                                         phase).                                  2010 (omit
                                                                                                 sections 5.1.2
                                                                                                 and 6.6).
Variable Refrigerant Flow Multi-  HP.................  <65,000 Btu/h (3-    SEER and HSPF.....  ANSI/AHRI 1230-     Paragraphs (c), (d), (e), and (f).
 split Systems, Air-cooled.                             phase).                                  2010 (omit
                                                                                                 sections 5.1.2
                                                                                                 and 6.6).
Variable Refrigerant Flow Multi-  AC and HP..........  >=65,000 Btu/h and   EER and COP.......  Appendix D of this  None.
 split Systems, Air-cooled.                             <760,000 Btu/h.                          subpart \2\.
                                                       >=65,000 Btu/h and   IEER and COP......  Appendix D1 of      None.
                                                        <760,000 Btu/h.                          this subpart \2\.
Variable Refrigerant Flow Multi-  HP.................  <760,000 Btu/h.....  EER and COP.......  Appendix D of this  None.
 split Systems, Water-source.                                                                    subpart \2\.
                                                       <760,000 Btu/h.....  IEER and COP......  Appendix D1 of      None.
                                                                                                 this subpart \2\.
Single Package Vertical Air       AC and HP..........  <760,000 Btu/h.....  EER and COP.......  AHRI 390-2003       Paragraphs (c) and (e).
 Conditioners and Single Package                                                                 (omit section
 Vertical Heat Pumps.                                                                            6.4).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Incorporated by reference; see Sec.   431.95.
\2\ For equipment with multiple appendices listed in this table 1, consult the notes at the beginning of those appendices to determine the applicable
  appendix to use for testing.

* * * * *

Appendix B to Subpart F of Part 431 [Reserved]

0
12. Add and reserve appendix B to subpart F of part 431.

Appendix C to Subpart F of Part 431 [Reserved]

0
13. Add and reserve appendix C to subpart F of part 431.
0
14. Add appendix D to subpart F of part 431 to read as follows:

Appendix D to Subpart F of Part 431--Uniform Test Method for Measuring 
the Energy Consumption of Variable Refrigerant Flow Multi-Split Air 
Conditioners and Heat Pumps (Other Than Air-Cooled With Rated Cooling 
Capacity Less Than 65,000 BTU/H)

    Note: Manufacturers must use the results of testing under this 
appendix to determine compliance with the relevant standard from 
Sec.  431.97 as that standard appeared in the January 1, 2021 
edition of 10 CFR parts 200-499. Specifically, before [Date 360 days 
after publication of the final rule in the Federal Register] 
representations must be based upon results generated either under 
this appendix or under 10 CFR 431.96 as it appeared in the 10 CFR 
parts 200-499 edition revised as of January 1, 2021.

    For any amended standards for variable refrigerant flow multi-
split air conditioners and heat pumps that rely on integrated

[[Page 70684]]

energy efficiency ratio (IEER) published after January 1, 2021, 
manufacturers must use the results of testing under appendix D1 of 
this subpart to determine compliance. Representations related to 
energy consumption must be made in accordance with the appropriate 
appendix that applies (i.e., appendix D or appendix D1) when 
determining compliance with the relevant standard.
    1. Incorporation by Reference.
    DOE incorporated by reference in Sec.  431.95, the entire 
standard for ANSI/AHRI 1230-2010. However, only enumerated 
provisions of that document apply to this appendix, as set forth in 
paragraph (1) of this section. To the extent there is a conflict, 
the language of the test procedure in this appendix takes precedence 
over the referenced test standard.
    (1) ANSI/AHRI 1230-2010:
    (i) Section 5.1.2--Manufacturer involvement is inapplicable as 
specified in section 2.1 of this appendix.
    (ii) Section 6.6--Verification testing and uncertainty is 
inapplicable as specified in section 2.2 of this appendix.
    2. General. Determine the energy efficiency ratio (EER) and 
coefficient of performance (COP) (as applicable) in accordance with 
ANSI/AHRI 1230-2010; however, the following enumerated provisions of 
that document are not applicable.
    (i) Section 5.1.2--Manufacturer involvement
    (ii) Section 6.6--Verification testing uncertainty
    Sections 3 through 6 of this appendix provide additional 
instructions for determining EER and COP.
    3. Optional break-in period. Manufacturers may optionally 
specify a ``break-in'' period, not to exceed 20 hours, to operate 
the equipment under test prior to conducting the test method 
specified in this appendix. A manufacturer who elects to use an 
optional compressor break-in period in its certification testing 
should record this period's duration as part of the information in 
the supplemental testing instructions under 10 CFR 429.43.
    4. Refrigerant line length corrections. For test setups where it 
is physically impossible for the laboratory to use the required line 
length listed in Table 3 of the ANSI/AHRI 1230-2010, then the actual 
refrigerant line length used by the laboratory may exceed the 
required length and the following cooling capacity correction 
factors are applied:

------------------------------------------------------------------------
 Piping length beyond minimum,   Piping length beyond   Cooling capacity
            X (ft)                  minimum, Y (m)       correction (%)
------------------------------------------------------------------------
0 > X <= 20...................  0 > Y <= 6.1.........                  1
20 > X <= 40..................  6.1 > Y <=12.2.......                  2
40 > X <= 60..................  12.2 > Y <= 18.3.....                  3
60 > X <= 80..................  18.3 > Y <= 24.4.....                  4
80 > X <= 100.................  24.4 > Y <= 30.5.....                  5
100 > X <= 120................  30.5 > Y <= 36.6.....                  6
------------------------------------------------------------------------

    5. Additional provisions for equipment set-up. The only 
additional specifications that may be used in setting up the basic 
model for test are those set forth in the installation and operation 
manual shipped with the unit. Each unit should be set up for test in 
accordance with the manufacturer installation and operation manuals. 
Sections 5.1 through 5.3 of this appendix provide specifications for 
addressing key information typically found in the installation and 
operation manuals.
    5.1. If a manufacturer specifies a range of superheat, sub-
cooling, and/or refrigerant pressure in its installation and 
operation manual for a given basic model, any value(s) within that 
range may be used to determine refrigerant charge or mass of 
refrigerant, unless the manufacturer clearly specifies a rating 
value in its installation and operation manual, in which case the 
specified rating value must be used.
    5.2. The airflow rate used for testing must be that set forth in 
the installation and operation manuals being shipped to the 
commercial customer with the basic model and clearly identified as 
that used to generate the DOE performance ratings. If a rated 
airflow value for testing is not clearly identified, a value of 400 
standard cubic feet per minute (scfm) per ton must be used.
    5.3. The test set-up and the fixed compressor speeds (i.e., the 
maximum, minimum, and any intermediate speeds used for testing) 
should be recorded and maintained as part of the test data 
underlying the certified ratings that is required to be maintained 
under 10 CFR 429.71.
    6. Manufacturer involvement in assessment or enforcement 
testing. A manufacturer's representative will be allowed to witness 
assessment and/or enforcement testing for variable refrigerant flow 
multi-split air conditioners and heat pumps. The manufacturer's 
representative will be allowed to inspect and discuss set-up only 
with a DOE representative. During testing, the manufacturer's 
representative may adjust only the modulating components that are 
necessary to achieve steady-state operation in the presence of a DOE 
representative. Only previously documented specifications for set-up 
as specified under sections 4 and 5 of this appendix will be used.
0
15. Add appendix D1 to subpart F of part 431 to read as follows:

Appendix D1 to Subpart F of Part 431--Uniform Test Method for Measuring 
the Energy Consumption of Variable Refrigerant Flow Multi-Split Air 
Conditioners and Heat Pumps (Other Than Air-Cooled With Rated Cooling 
Capacity Less Than 65,000 BTU/H)

    Note: Manufacturers must use the results of testing under this 
appendix to determine compliance with any amended standards for 
variable refrigerant flow multi-split air conditioners and heat 
pumps provided in Sec.  431.97 that are published after January 1, 
2021, and that rely on integrated energy efficiency ratio (IEER). 
Representations related to energy consumption must be made in 
accordance with the appropriate appendix that applies (i.e., 
appendix D or appendix D1) when determining compliance with the 
relevant standard.

    1. Incorporation by Reference.
    DOE incorporated by reference in Sec.  431.95, the entire 
standard for AHRI Standard 1230-2021, and ANSI/ASHRAE Standard 37-
2009. However, only enumerated provisions of these documents apply 
to this appendix, as set forth in paragraphs (1) and (2) of this 
section. To the extent there is a conflict, the language of the test 
procedure in this appendix takes precedence over the referenced test 
standards.
    (1) AHRI 1230-2021:
    (i) Section 3--Definitions, except section 3.10, is applicable 
as specified in section 2.1.1 of this appendix,
    (ii) Section 5--Test Requirements, except section 5.1.2, is 
applicable as specified in section 2.1.2 of this appendix,
    (iii) Section 6--Rating Requirements, except sections 6.3.3 and 
6.5, is applicable as specified in section 2.1.3 of this appendix,
    (iv) Section 11--Calculations is applicable as specified in 
section 2.1.4 of this appendix,
    (v) Section 12--Symbols, Subscripts and Superscripts is 
applicable as specified in section 2.1.5 of this appendix,
    (vi) Appendix E--ANSI/ASHRAE Standard 37-2009 Clarifications/
Exceptions--Normative is applicable as specified in section 2.1.6 of 
this appendix,
    (2) ANSI/ASHRAE 37-2009 (including Errata Sheet issued October 
3, 2016):
    (i) Section 1--Purpose is inapplicable as specified in section 
2.2.1 of this appendix,
    (ii) Section 2--Scope is inapplicable as specified in section 
2.2.2 of this appendix, and
    (iii) Section 4--Classification is inapplicable as specified in 
section 2.2.3 of this appendix.
    (2) General. Determine IEER and coefficient of performance (COP) 
(as applicable) in accordance with AHRI 1230-2021 and ANSI/ASHRAE 
37-2009 (including Errata Sheet issued on October 3, 2016; however, 
only the following enumerated provisions of those documents apply.
    2.1. Applicable Sections of AHRI 1230-2021

[[Page 70685]]

    2.1.1. Section 3--Definitions (Except Section 3.10--Definition 
of Critical Parameter(s)),
    2.1.2. Section 5--Test Requirements (Except Sections 5.1.2.1, 
5.1.2.2, and 5.1.2.3--Control Settings),
    2.1.3. Section 6--Rating Requirements (Except Section 6.3.3--
Allowable Critical Parameter Adjustments and Section 6.5--
Simultaneous Cooling and Heating Efficiency and Capacity Ratings),
    2.1.4. Section 11--Calculations,
    2.1.5. Section 12--Symbols, Subscripts and Superscripts,
    2.1.6. Appendix E--ANSI/ASHRAE 37-2009 Clarifications/
Exceptions--Normative
    Note: The controls verification procedure specified in Appendix 
C of AHRI 1230-2021 is referenced as part of DOE's certification 
provisions at Sec.  429.43(b) and product-specific enforcement 
provisions located at Sec.  429.134(s)(3).
    2.2. Excepted sections of ANSI/ASHRAE 37-2009 (including Errata 
Sheet issued October 3, 2016)
    2.2.1. Section 1--Purpose
    2.2.2. Section 2--Scope
    2.2.3. Section 4--Classifications
    Sections 3 through 5 of this appendix provide additional 
instructions for determining IEER and COP. In cases where there is a 
conflict, the language of this appendix takes highest precedence, 
followed by AHRI 1230-2021, followed by ANSI/ASHRAE 37-2009 
(including Errata Sheet issued October 3, 2016).
    3. Definitions
    3.1. Critical Parameter(s) are the following settings of 
modulating components of variable refrigerant flow multi-split air 
conditioners and heat pumps: compressor speed(s), outdoor fan 
speed(s) and outdoor variable valve position(s).
    4. Test Conditions
    4.1 Test Conditions for air-cooled VRF multi-split systems with 
rated cooling capacity greater than 65,000 Btu/h. When testing to 
certify to the energy conservation standards in Sec.  431.97, test 
using the ``Standard Rating Conditions, Cooling'' and ``Standard 
Rating Part-Load Conditions (IEER)'' conditions for cooling mode 
tests and ``Standard Rating Conditions (High Temperature Steady-
state Test for Heating)'' conditions for heat pump heating mode 
tests, as specified in Table 9 of AHRI 1230-2021.
    4.1.1 Representations of COP for air-cooled VRF multi-split 
systems with rated cooling capacity greater than 65,000 Btu/h made 
using the ``Low Temperature Operation, Heating'' condition specified 
in Table 9 of AHRI 1230-2021 are optional.
    4.2 Test Conditions for water-source VRF multi-split systems. 
When testing to certify to the energy conservation standards in 
Sec.  431.97, test using the ``Part-load Conditions (IEER)'' 
conditions specified for ``Water Loop Heat Pumps'' in Table 10 of 
AHRI 1230-2021 for cooling mode tests and the ``Standard Rating 
Test'' conditions specified for ``Water Loop Heat Pumps'' in Table 
11 of AHRI 1230-2021 for heat pump heating mode tests.
    4.2.1 For water-source VRF multi-split systems, representations 
of EER made using the ``Standard Rating Test'' conditions specified 
for ``Ground-loop Heat pumps'' in Table 10 of AHRI 1230-2021 and 
representations of COP made using the ``Standard Rating Test'' 
conditions specified for ``Ground-loop Heat Pumps'' in Table 11 of 
AHRI 1230-2021 are optional.
    5. Test Procedure
    5.1 Control Settings. Control settings must be set in accordance 
with sections 5.1.3, 5.1.4, 5.1.5, and 5.2 of AHRI 1230-2021. For 
units equipped with head pressure controls, the head pressure 
controls must be set per manufacturer installation instructions or 
per factory settings if no instructions are provided. Indoor 
airflow-control settings must be set in accordance with Section 
6.3.1 of AHRI 1230-2021. At each load point, critical parameters 
must be set to the values certified in the STI. In cases where a 
certified critical parameter value is not in the STI, the system 
must operate per commands from the system controls for that 
parameter. Once set, control settings must remain unchanged for the 
remainder of the test (except for allowable adjustment of critical 
parameters as described in section 5.2 of this appendix).
    5.2 Allowable Critical Parameter Adjustments for IEER cooling 
tests. The following sections describe allowable adjustments to 
critical parameters after the initial system setup (during which all 
control settings, including certified critical parameters, are set). 
Adjust critical parameters in order to achieve full- and part-load 
cooling capacity targets and SHR limits.
    5.2.1 Critical Parameter Adjustments for Meeting Cooling 
Capacity Targets. Once critical parameters have been set to the 
values certified in the STI, if the unit cannot operate within 3% of 
the target cooling capacity (i.e., within 3% of the load fraction 
for a given part-load cooling test (75%, 50%, or 25% load) or within 
3% of the certified cooling capacity for a 100% full-load cooling 
test), manually-controlled critical parameters must be adjusted 
according to the following provisions:
    5.2.1.1. Cooling Capacity is Below Lower Tolerance. If, for any 
test, the cooling capacity operates below the lower tolerance for 
the target cooling capacity, increase the compressor speed(s) beyond 
the STI-certified value(s) until the cooling capacity operates 
within 3% of the target cooling capacity. If multiple compressors 
are present in the system, increase compressor speed by the same 
absolute increment in RPM or Hz for each compressor for which the 
following conditions apply:
    (1) The STI specifies a non-zero compressor speed for the 
compressor for that test and
    (2) The compressor has not yet reached its maximum capable 
operating speed. The compressor speed(s) must not be less than the 
STI-certified value(s) at any point during the test. Upward 
adjustments to compressor speed are not constrained by a budget on 
RSS Points Total (See section 5.2.1.2.1 of this appendix).
    5.2.1.2 Cooling Capacity is Above Upper Tolerance. If, for any 
test, the cooling capacity operates above the upper tolerance for 
the target cooling capacity, adjust any manually-controlled critical 
parameters per the STI. If the STI does not include a hierarchy of 
instructions for adjustment of critical parameters to reduce cooling 
capacity during IEER cooling tests, then reduce only the compressor 
speed(s) to reduce cooling capacity. If multiple compressors are 
present in the system, decrease compressor speed by the same 
absolute increment for each compressor for which the following 
conditions apply:
    (1) The STI specifies a non-zero compressor speed for the 
compressor for that test and
    (2) The compressor has not yet reached minimum speed. Continue 
reducing cooling capacity in this manner until one of the following 
occurs:
    (i) The unit operates within 3% of the target cooling capacity; 
or
    (ii) The RSS point total reaches a budget of 70 points (See 
section 5.2.1.2.1 of this appendix). For the 75%, 50% and 25% part-
load cooling test points, if the RSS point total reaches 70 during 
critical parameter adjustments before the capacity operates within 
3% of the target cooling capacity, stop adjustment and follow cyclic 
degradation procedures in accordance with Section 11.2.2.1 of AHRI 
1230-2021.
    5.2.1.2.1 Measuring Critical Parameter Variation During 
Adjustment Period. When adjusting critical parameters to reduce 
cooling capacity, critical parameter variation must be calculated 
each time the critical parameters are adjusted, using the following 
equations:
    First, use equation 5.2-1 to calculate the absolute parameter 
percent difference (PPDi) between each adjusted critical parameter 
and the value for that parameter certified in the supplemental 
testing instructions provided by the manufacturer pursuant to Sec.  
429.43(b)(4) of this chapter (STI).
[GRAPHIC] [TIFF OMITTED] TP10DE21.010

Where:

``i'' identifies the critical parameter--either compressors 
speed(s), outdoor fan speed(s), or outdoor variable valve 
position(s)
CPi,Adj = The adjusted position of critical parameter ``i'', 
recorded at each measurement interval. If multiple components 
corresponding to a single parameter are present (e.g., multiple 
compressors), calculate the average position across all components 
corresponding to that parameter at each

[[Page 70686]]

measurement interval when determining CPi,adj .
CPi,STI = The position of critical parameter ``i'' as certified in 
the STI. If multiple components corresponding to a single parameter 
are present, calculate the average position across all components 
corresponding to that parameter at each measurement interval when 
determining CPi,STI .
CPMax = The maximum operating position for Critical Parameter ``i'', 
as certified in the STI for the 100% load condition. If multiple 
components corresponding to a single parameter are present, 
calculate as the average value across all components corresponding 
to that critical parameter certified in the STI for the 100% load 
condition.

    Next, use equation 5.2-2 to determine the accrued points for 
each critical parameter:
[GRAPHIC] [TIFF OMITTED] TP10DE21.011

Where:

    ``i'' identifies the critical parameter--either compressors 
speed(s), outdoor fan speed(s), or outdoor variable valve 
position(s)
NPVi = the nominal point value for critical parameter ``i'', as 
follows:

           Table 5.1--Critical Parameter Nominal Point Values
------------------------------------------------------------------------
                                                           Nominal point
                   Critical parameter                          value
------------------------------------------------------------------------
Compressor Speed(s).....................................              13
Outdoor Fan Speed(s)....................................               7
Outdoor Variable Valve position(s)......................               1
------------------------------------------------------------------------

    Finally, use equation 5.2-3 to calculate the root-sum-squared 
(RSS) Points Total across all critical parameters.
[GRAPHIC] [TIFF OMITTED] TP10DE21.012

    5.2.2 Critical Parameter Adjustments for Meeting SHR Limits. The 
SHR for the 100% load test point and the 75% part-load test point 
must not be higher than 0.82 and 0.85, respectively (measured to the 
nearest hundredth). If the SHR is above the allowable limit, 
increase the compressor speed(s) until either the SHR is less than 
or equal to the allowable limit or the cooling capacity reaches 3% 
greater than the target cooling capacity for that test, whichever 
happens first. If multiple compressors are present in the system, 
increase compressor speed by the same absolute increment for each 
compressor for which the following conditions apply:
    (1) The STI specifies a non-zero compressor speed for the 
compressor for that test and
    (2) The compressor has not yet reached maximum speed. Upwards 
adjustments to compressor speed are not constrained by a budget on 
RSS Points Total. Should the SHR remain above the maximum limit when 
the cooling capacity reaches its upper 3% tolerance, no further 
compressor adjustments must be made, and the calculation procedures 
specified in Section 11.2.2.2 of AHRI 1230-2021 must be applied 
using the adjusted SHR value obtained after increasing the 
compressor speed(s).
    6. Set-Up and Test Provisions for Specific Components. When 
testing a VRF multi-split system that includes any of the specific 
components listed in Table 6.1, test in accordance with the set-up 
and test provisions specified in Table 6.1.

           Table 6.1--Test Provisions for Specific Components
------------------------------------------------------------------------
          Component                Description         Test provisions
------------------------------------------------------------------------
Desiccant Dehumidification    An assembly that      Disable desiccant
 Components.                   reduces the           dehumidification
                               moisture content of   components for
                               the supply air        testing.
                               through moisture
                               transfer with solid
                               or liquid
                               desiccants.
Air Economizers.............  An automatic system   For any air
                               that enables a        economizer that is
                               cooling system to     factory-installed,
                               supply outdoor air    place the
                               to reduce or          economizer in the
                               eliminate the need    100% return
                               for mechanical        position and close
                               cooling during mid    and seal the
                               or cold weather.      outside air dampers
                                                     for testing. For
                                                     any modular air
                                                     economizer shipped
                                                     with the unit but
                                                     not factory-
                                                     installed, do not
                                                     install the
                                                     economizer for
                                                     testing.
Fresh Air Dampers...........  An assembly with      For any fresh air
                               dampers and means     dampers that are
                               to set the damper     factory-installed,
                               position in a         close and seal the
                               closed and one open   dampers for
                               position to allow     testing. For any
                               air to be drawn       modular fresh air
                               into the equipment    dampers shipped
                               when the indoor fan   with the unit but
                               is operating.         not factory-
                                                     installed, do not
                                                     install the dampers
                                                     for testing.
Hail Guards.................  A grille or similar   Remove hail guards
                               structure mounted     for testing.
                               to the outside of
                               the unit covering
                               the outdoor coil to
                               protect the coil
                               from hail, flying
                               debris and damage
                               from large objects.
Low Ambient Cooling Dampers.  An assembly with      Remove low ambient
                               dampers and means     cooling dampers for
                               to set the dampers    testing.
                               in a position to
                               recirculate the
                               warmer condenser
                               discharge air to
                               allow for reliable
                               operation at low
                               outdoor ambient
                               conditions.
Power Correction Capacitors.  A capacitor that      Remove power
                               increases the power   correction
                               factor measured at    capacitors for
                               the line connection   testing.
                               to the equipment.
                               These devices are a
                               requirement of the
                               power distribution
                               system supplying
                               the unit.

[[Page 70687]]

 
Ventilation Energy Recovery   An assembly that      For any VERS that is
 Systems (VERS).               preconditions         factory-installed,
                               outdoor air           place the VERS in
                               entering the          the 100% return
                               equipment through     position and close
                               direct or indirect    and seal the
                               thermal and/or        outside air dampers
                               moisture exchange     and exhaust air
                               with the exhaust      dampers for
                               air, which is         testing, and do not
                               defined as the        energize any VERS
                               building air being    subcomponents
                               exhausted to the      (e.g., energy
                               outside from the      recovery wheel
                               equipment.            motors). For any
                                                     VERS module shipped
                                                     with the unit but
                                                     not factory-
                                                     installed, do not
                                                     install the VERS
                                                     for testing.
------------------------------------------------------------------------

[FR Doc. 2021-26288 Filed 12-9-21; 8:45 am]
BILLING CODE 6450-01-P