# Energy Conservation Program: Test Procedure for Room Air Conditioners > Briefs, arguments, decisions, and more. URL: https://www.frixlaw.com/law-library/documents/fr%3A2021-05415 ## Record - **Collection:** Federal Register - **Document type:** Rule - **Published:** March 29, 2021 - **Citation:** 86 FR 16446 ## Text DEPARTMENT OF ENERGY 10 CFR Parts 429 and 430 [EERE-2017-BT-TP-0012] RIN 1904-AD47 Energy Conservation Program: Test Procedure for Room Air Conditioners AGENCY: Office of Energy Efficiency and Renewable Energy, Department of Energy. ACTION: Final rule. SUMMARY: On June 11, 2020, the U.S. Department of Energy (“DOE”) issued a notice of proposed rulemaking (“NOPR”) to amend the test procedure for room air conditioners (“room ACs”). That proposed rulemaking serves as the basis for the final rule. Specifically, this final rule adopts the following updates to the test procedure for room ACs at appendix F: Incorporate by reference current versions of applicable industry standards; establish test provisions to measure energy use of variable-speed room ACs during a representative average use cycle; update definitions to define key terms and support provisions for testing variable-speed room ACs; and incorporate specifications and minor corrections to improve the test procedure repeatability, reproducibility, and overall readability. This final rule does not modify the test procedures for single-speed room ACs and does not affect the measured energy use for these models. The provisions established to measure energy use of variable-speed room ACs will improve the representativeness of the measured energy use of these models. DATES: Effective date: The effective date of this rule is April 28, 2021. Compliance date: The final rule changes will be mandatory for product testing starting September 27, 2021. Incorporation by reference: The incorporation by reference of certain publications listed in the rule is approved by the Director of the Federal Register on April 28, 2021. The incorporation by reference of certain other publications listed in this rulemaking were approved by the Director of the Federal Register on March 7, 2012, and July 31, 2015. ADDRESSES: The docket, which includes Federal Register notices, public meeting attendee lists and transcripts, comments, and other supporting documents/materials, is available for review at http://www.regulations.gov. All documents in the docket are listed in the http://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. A link to the docket web page can be found at https://www.regulations.gov/docket?D=EERE-2017-BT-TP-0012. The docket web page contains instructions on how to access all documents, including public comments, in the docket. For further information on how to review the docket contact the Appliance and Equipment Standards Program staff at (202) 287-1445 or by email: ApplianceStandardsQuestions@ee.doe.gov. FOR FURTHER INFORMATION CONTACT: Mr. Bryan Berringer, 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) 586-0371. Email: ApplianceStandardsQuestions@ee.doe.gov. Ms. Sarah Butler, U.S. Department of Energy, Office of the General Counsel, GC-33, 1000 Independence Avenue SW, Washington, DC 20585-0121. Telephone: (202) 586-1777. Email: Sarah.Butler@hq.doe.gov. SUPPLEMENTARY INFORMATION: DOE maintains previously approved incorporation by references and incorporates by reference the following industry standards into title 10, Code of Federal Regulations (“CFR”), part 430: Association of Home Appliance Manufacturers (“AHAM”) RAC-1-2020, (“AHAM RAC-1-2020”), “Room Air Conditioners;” American National Standards Institute (“ANSI”)/American Society of Heating, Refrigerating, and Air-Conditioning Engineers (“ASHRAE”) Standard 16-2016, (“ANSI/ASHRAE Standard 16-2016”), “Method of Testing for Rating Room Air Conditioners, Packaged Terminal Air Conditioners, and Packaged Terminal Heat Pumps for Cooling and Heating Capacity;” ANSI approved October 31, 2016. ANSI/ASHRAE Standard 41.1-2013, (“ANSI/ASHRAE Standard 41.1”), “Standard Method for Temperature Measurement;” ANSI approved January 30, 2013. ANSI/ASHRAE Standard 41.2-1987 (RA 1992), (“ANSI/ASHRAE Standard 41.2-1987 (RA 1992)”), “Standard Methods for Laboratory Airflow Measurement;” ANSI reaffirmed April 20, 1992. ANSI/ASHRAE Standard 41.3-2014, (“ANSI/ASHRAE Standard 41.3-2014”), “Standard Methods for Pressure Measurement;” ANSI approved July 3, 2014. ANSI/ASHRAE Standard 41.6-2014, (“ANSI/ASHRAE Standard 41.6-2014”), “Standard Method for Humidity Measurement;” ANSI approved July 3, 2014. ANSI/ASHRAE Standard 41.11-2014, (“ANSI/ASHRAE Standard 41.11-2014”), “Standard Methods for Power Measurement;” ANSI approved July 3, 2014. International Electrotechnical Commission (“IEC”) Standard 62301, (“IEC Standard 62301 Second Edition”), “Household electrical appliances—Measurement of standby power, (Edition 2.0, 2011-01)”. Copies of AHAM RAC-1-2020 can be obtained from the Association of Home Appliance Manufacturers at https://www.aham.org/ht/d/Store/. Copies of ANSI/ASHRAE Standard 16-2016, ANSI/ASHRAE Standard 41.1-2013, ANSI/ASHRAE Standard 41.2-1987, ANSI/ASHRAE Standard 41.3-2014, ANSI/ASHRAE Standard 41.6-2014, and ANSI/ASHRAE Standard 41.11-2014 can be obtained from the American National Standards Institute at https://webstore.ansi.org/. Copies of IEC Standard 62301 can be obtained from http://webstore.iec.ch. See section IV.N of this document for additional information on these standards. Table of Contents I. Authority and Background A. Authority B. Background II. Synopsis of the Final Rule III. Discussion A. Room Air Conditioner Definition B. Industry Test Standards 1. AHAM RAC-1 2. ANSI/ASHRAE Standard 16 3. ANSI/ASHRAE Standards 41.1, 41.2, 41.3, 41.6, and 41.11 C. Variable-Speed Room Air Conditioner Test Procedure 1. Methodology 2. Test Conditions 3. Variable-Speed Compressor Operation 4. Capacity and Electrical Power Adjustment Factors 5. Cycling Loss Factors 6. Test Condition Weighting Factors 7. Weighted CEER and Performance Adjustment Factor 8. Air-Enthalpy Test Alternative 9. Product Specific Reporting Provisions 10. Estimated Annual Operating Cost Calculation D. Definitions 1. Key Terms 2. Compressor Speeds E. Active Mode Testing 1. Cooling Mode 2. Heating Mode 3. Off-Cycle Mode F. Standby Modes and Off Mode 1. Referenced Standby Mode and Off Mode Test Standard G. Network Functionality H. Demand Response I. Combined Energy Efficiency Ratio J. Certification and Verification Requirements K. Reorganization of Calculations in 10 CFR 430.23 L. Effective Date, Compliance Date and Waivers M. Test Procedure Costs and Impact 1. Appendix F 2. Additional Amendments 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. Congressional Notification N. Description of Materials Incorporated by Reference V. Approval of the Office of the Secretary I. Authority and Background Room ACs are included in the list of “covered products” for which DOE is authorized to establish and amend energy conservation standards and test procedures. (42 U.S.C. 6292(a)(2)) DOE's energy conservation standards and test procedure for room ACs are currently prescribed at 10 CFR 430.32(b) and 10 CFR 430.23(f), respectively. The following sections discuss DOE's authority to establish test procedures for room ACs and relevant background information regarding DOE's consideration of test procedures for this product. A. Authority The Energy Policy and Conservation Act, as amended (“EPCA”), 1 authorizes DOE to regulate the energy efficiency of a number of consumer products and certain industrial equipment. (42 U.S.C. 6291-6317) Title III, Part B 2 of EPCA established the Energy Conservation Program for Consumer Products Other Than Automobiles, which sets forth a variety of provisions designed to improve energy efficiency. These products include room ACs, the subject of this document. (42 U.S.C. 6292(a)(2)) 1 All references to EPCA in this document refer to the statute as amended through Energy Act of 2020, Public Law 116-260 (Dec. 27, 2020). 2 For editorial reasons, upon codification in the U.S. Code, Part B was redesignated Part A. The energy conservation program under EPCA consists essentially of four parts: (1) Testing, (2) labeling, (3) Federal energy conservation standards, and (4) certification and enforcement procedures. Relevant provisions of EPCA specifically include definitions (42 U.S.C. 6291), test procedures (42 U.S.C. 6293), labeling provisions (42 U.S.C. 6294), energy conservation standards (42 U.S.C. 6295), and the authority to require information and reports from manufacturers (42 U.S.C. 6296). The testing requirements consist of test procedures that manufacturers of covered products must use as the basis for (1) certifying to DOE that their products comply with the applicable energy conservation standards adopted under EPCA (42 U.S.C. 6295(s)), and (2) making representations about the efficiency of those products (42 U.S.C. 6293(c)). Similarly, DOE must use these test procedures to determine whether the products comply with any relevant standards promulgated under EPCA. (42 U.S.C. 6295(s)) Federal energy efficiency requirements for covered products established under EPCA generally supersede State laws and regulations concerning energy conservation testing, labeling, and standards. (42 U.S.C. 6297) DOE may, however, grant waivers of Federal preemption for particular State laws or regulations, in accordance with the procedures and other provisions of EPCA. (42 U.S.C. 6297(d)) Under 42 U.S.C. 6293, EPCA sets forth the criteria and procedures DOE must follow when prescribing or amending test procedures for covered products. EPCA provides that any test procedures prescribed or amended under this section shall be reasonably designed to produce test results which measure energy efficiency, energy use or estimated annual operating cost of a covered product during a representative average use cycle or period of use and shall not be unduly burdensome to conduct. (42 U.S.C. 6293(b)(3)) EPCA also requires that, at least once every 7 years, DOE evaluate test procedures for each type of covered product, including room ACs, to determine whether amended test procedures would more accurately or fully comply with the requirements of 42 U.S.C. 6293(b)(3). (42 U.S.C. 6293(b)(1)(A)) If the Secretary determines, on his own behalf or in response to a petition by any interested person, that a test procedure should be prescribed or amended, the Secretary shall promptly publish in the Federal Register proposed test procedures and afford interested persons an opportunity to present oral and written data, views, and arguments with respect to such procedures. The comment period on a proposed rule to amend a test procedure shall be at least 60 days and may not exceed 270 days. In prescribing or amending a test procedure, the Secretary shall take into account such information as the Secretary determines relevant to such procedure, including technological developments relating to energy use or energy efficiency of the type (or class) of covered products involved. (42 U.S.C. 6293(b)(2)) If DOE determines that test procedure revisions are not appropriate, DOE must publish its determination not to amend the test procedures. DOE is publishing this final rule in satisfaction of the 7-year review requirement specified in EPCA. (42 U.S.C. 6293(b)(1)(A)) In addition, EPCA requires that DOE amend its test procedures for all covered products to integrate measures of standby mode and off mode energy consumption into the overall energy efficiency, energy consumption, or other energy descriptor, unless the current test procedure already incorporates the standby mode and off mode energy consumption, or if such integration is technically infeasible. (42 U.S.C. 6295(gg)(2)(A)) If an integrated test procedure is technically infeasible, DOE must prescribe separate standby mode and off mode energy use test procedures for the covered product, if a separate test is technically feasible. ( Id. ) Any such amendment must consider the most current versions of the International Electrotechnical Commission (“IEC”) Standard 62301 3 and IEC Standard 62087 4 as applicable. (42 U.S.C. 6295(gg)(2)(A)) 3 IEC 62301, Household electrical appliances—Measurement of standby power (Edition 2.0, 2011-01). 4 IEC 62087, Methods of measurement for the power consumption of audio, video, and related equipment (Edition 3.0, 2011-04). B. Background DOE's existing test procedure for room ACs appears at Title 10 of the CFR part 430, subpart B, appendix F (“Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners” (“appendix F”)), and the room AC performance metric calculations are codified at 10 CFR 430.23(f). DOE most recently amended the test procedure for room ACs in a final rule published on January 6, 2011, (hereafter the “January 2011 Final Rule”), which added a test procedure to measure standby mode and off mode power and to introduce a new combined efficiency metric, Combined Energy Efficiency Ratio (“CEER”), that accounts for energy consumption in active mode, standby mode, and off mode. 76 FR 971. The previous room AC test procedure incorporates by reference three industry test methods: (1) American National Standards Institute (“ANSI”)/Association of Home Appliance Manufacturers (“AHAM”) RAC-1-2008, “Room Air Conditioners” (“ANSI/AHAM RAC-1-2008”), 5 (2) ANSI/American Society of Heating, Refrigerating, and Air-Conditioning Engineers (“ASHRAE”) Standard 16-1983 (RA 2009), “Method of Testing for Rating Room Air Conditioners and Packaged Terminal Air Conditioners” (“ANSI/ASHRAE Standard 16-2009”), 6 and (3) IEC Standard 62301, “Household electrical appliances—Measurement of standby power (first edition June 2005)” (“IEC Standard 62301 First Edition”). 7 5 Copies can be purchased from http://webstore.ansi.org. 6 Copies can be purchased from http://www.techstreet.com. 7 Copies can be purchased from http://webstore.iec.ch. On May 8, 2019, DOE published a Decision and Order, granting a waiver for certain room AC models with variable-speed capabilities in response to a petition from LG Electronic USA, Inc. (“LG”). 84 FR 20111 (“LG Waiver”). As required under the waiver, the specified LG variable-speed room ACs must be tested at four different outdoor temperatures instead of a single outdoor temperature, with the unit compressor speed fixed at each temperature. This approach for the alternate test procedure was derived from the current DOE test procedure for central air conditioners (10 CFR part 430, subpart B, appendix M (“appendix M”)). The LG Waiver provides definitions for each fixed compressor speed, adjusts the annual energy consumption and operating cost calculations that provide the basis for the information presented to consumers on the EnergyGuide Label, and requires that compressor speeds be set in accordance with instructions submitted to DOE by LG on April 2, 2019. 8 84 FR 20111, 20118-20121. 8 While the instructions provided by LG on April 2, 2019 are listed in the docket for this rulemaking, they were marked as confidential and were treated accordingly. On May 26, 2020, DOE published a Decision and Order, granting a waiver to GD Midea Air Conditioning Equipment Co. LTD. (“Midea”) for six variable-speed basic models with the condition that Midea must test and rate these models according to an alternate test procedure that is substantively consistent with that prescribed by in the LG Waiver, and report product-specific information that reflects the alternate test procedure. 85 FR 31481 (“Midea Waiver”). On June 11, 2020, DOE published a notice of proposed rulemaking (“June 2020 NOPR”) proposing amendments to the test procedures for room ACs to: (1) Update to the latest versions of industry test methods that are incorporated by reference; (2) adopt new testing provisions for variable-speed room ACs that reflect the relative efficiency gains at reduced cooling loads; (3) adopt new definitions consistent with these two proposed amendments; and (4) provide specifications and minor corrections to improve the test procedure repeatability, reproducibility, and overall readability. 85 FR 35700. DOE received comments in response to the June 2020 NOPR from the interested parties listed in Table II.1. Table II.1—June 2020 NOPR Written Comments Commenter(s) Reference in this NOPR Commenter type Association of Home Appliance Manufacturers AHAM Trade Association. California Investor-Owned Utilities California IOUs Utility. Appliance Standards Awareness Project (“ASAP”), American Council for an Energy-Efficient Economy (“ACEEE”), Natural Resources Defense Council (“NRDC”) Joint Commenters Efficiency Organizations. Northwest Energy Efficiency Alliance NEAA Efficiency Organization. Keith Rice Rice Consultant. GE Appliances, a Haier Company GEA Manufacturer. Subsequent to the publication of the June 2020 NOPR, on September 23, 2020, DOE granted GE Appliances, a Haier Company (“GEA)” an interim waiver from the room AC test procedure for the 18 basic models listed in GEA's petition, using an alternate test procedure consistent with that granted to Midea in the Midea Waiver. 85 FR 59770. (“GEA Interim Waiver”) Additionally, on February 14, 2020, DOE published its updated Process Rule to improve the internal framework for establishing new energy efficiency regulations, with the goal of increasing transparency, accountability, and certainty for stakeholders. 85 FR 8626. As required under the updated Process Rule, DOE will adopt industry test standards as DOE test procedures for covered products and equipment, unless such methodology would be unduly burdensome to conduct or would not produce test results that reflect the energy efficiency, energy use, water use (as specified in EPCA) or estimated operating costs of that equipment during a representative average use cycle. Section 8(c) of 10 CFR part 430 subpart C appendix A. See also, 85 FR 8626, 8708. II. Synopsis of the Final Rule In this final rule, DOE amends the existing test procedure for room ACs to: (1) Incorporate by reference current versions of the applicable industry standards; (2) adopt test provisions for variable-speed room ACs that reflect energy efficiency during a representative average use cycle; (3) update definitions to define key terms and support the adopted provisions for testing variable-speed room ACs; and (4) update specifications and implement minor corrections to improve the test procedure repeatability, reproducibility, and overall readability. DOE has determined that the amendments will both provide efficiency measurements more representative of the energy efficiency of variable-speed room ACs and will not alter the measured efficiency of single-speed room ACs, which constitute the large majority of units on the market. DOE has determined that the amended test procedure will not be unduly burdensome to conduct. DOE's actions are summarized in Table II.2 and addressed in detail in section III of this document. Table II.2—Summary of Changes in the Amended Test Procedure Previous DOE test procedure Amended test procedure Attribution References industry standards— Updates references to applicable sections of: Industry test procedure updates. • ANSI/AHAM RAC-1-2008, • AHAM RAC-1-2020, • ANSI/ASHRAE Standard 16-2009, and • ANSI/ASHRAE Standard 16-2016 (including relevant cross-referenced industry standards), and • IEC Standard 62301 First Edition • IEC Standard 62301 Second Edition. Testing, calculation of CEER metric, and certification for all room ACs based on single temperature rating condition Relevant definitions, testing, calculation of CEER metric, and certification for variable-speed room ACs based on additional reduced outdoor temperature test conditions In response to test procedure waivers. Definitions— —Definition of “room air conditioner” does not explicitly include function of providing cool conditioned air to an enclosed space, and references “prime,” an undefined term, to describe the source of refrigeration. —Adds the word “cooled” to describe the conditioned air a room AC provides and the phrase “notwithstanding ASHRAE 16 and RAC-1 (incorporated by reference; see § 430.3)” to reiterate that the DOE definition takes precedence over conflicting language in relevant industry standards, in the definition of “room air conditioner” and removes “prime” from the definition. Added by DOE (clarification). —“Cooling mode,” “cooling capacity,” “combined energy efficiency ratio,” are undefined terms. —Adds definition for “cooling mode,” “cooling capacity,” and “combined energy efficiency ratio.” Appendix F does not explicitly identify the scope of the test procedure. Creates new section indicating the appendix applies to the energy performance of room ACs. Added by DOE (specifies the applicability of the test procedure). Provides that test unit be installed in a manner similar to consumer installation. —References ANSI/ASHRAE Standard 16-2016, specifying that the perimeter of louvered room ACs be sealed to the separating partition, consistent with common testing practice. Industry test procedure update and added by DOE (additional installation specifications). —Specifies that non-louvered room ACs be installed inside a compatible wall sleeve, with the manufacturer-provided installation materials. Calculations for average annual energy consumption, combined annual energy consumption, energy efficiency ratio (“EER”), and CEER are located in 10 CFR 430.23(f). —Moves calculations for CEER and annual energy consumption for each operating mode into appendix F. —Removes EER calculation and references entirely, as it is obsolete. Added by DOE (improve readability). The effective date for the amended test procedure adopted in this final rule is 30 days after publication of this document in the Federal Register . Representations of energy use or energy efficiency must be based on testing in accordance with the amended test procedure beginning 180 days after the publication of this final rule. III. Discussion A. Room Air Conditioner Definition DOE defines a “room air conditioner” as a consumer product, other than a packaged terminal air conditioner, which is powered by a single-phase electric current and which is an encased assembly designed as a unit for mounting in a window or through the wall for the purpose of providing delivery of conditioned air to an enclosed space. It includes a prime source of refrigeration and may include a means for ventilating and heating. 10 CFR 430.2. In the June 2020 NOPR, DOE proposed adding the term “cooled” to the room AC definition, so that it refers to a system that “. . . delivers cooled , conditioned air to an enclosed space . . .” (emphasis added). 85 FR 35700, 35705 (Jun. 11, 2020). DOE believed that this revised wording would better represent the key function of a room AC, and would avoid any potential for the room AC definition to cover other indoor air quality systems that could be described as “conditioning” the air, but that would not be appropriately included within the scope of coverage of a room AC. Id. Additionally, as described previously, the previous definition of room AC specified that it includes a prime source of refrigeration. Id. DOE contended that using the word “prime” to describe the source of refrigeration in the previous definition was extraneous and could be construed as referring to a “primary” refrigeration system, a distinction that could inadvertently exclude future products that implement a different technology as the primary source of air conditioning, while implementing a refrigeration loop as the “secondary” means of cooling or heating. Id. Primary and secondary means of conditioning air are not uncommon in certain refrigeration products and chiller systems; in fact, some room ACs with heating functionality implement a resistance heater as a supplemental form of heating to the primary heat pump, for use under extreme temperature conditions. DOE also noted that the recently codified portable AC definition was not limited to products with a prime source of refrigeration. Id. For these reasons, DOE proposed to remove the word “prime” from the room AC definition. DOE also proposed to add to the phrase “notwithstanding ASHRAE 16 and RAC-1 (incorporated by reference; see § 430.3),” to the room air conditioner definition to reiterate that the DOE definition takes precedence over conflicting language in relevant industry standards. Id. Additionally, DOE proposed to reorganize the room AC definition to improve its readability. Id. The minor editorial revisions and specifications discussed in this section do not modify the scope of the room AC definition. In summary, DOE proposed to modify the room AC definition in 10 CFR 430.2 to read as follows: “ Room air conditioner means a window-mounted or through-the-wall-mounted encased assembly, other than a `packaged terminal air conditioner,' that delivers cooled, conditioned air to an enclosed space, and is powered by single-phase electric current. It includes a source of refrigeration and may include additional means for ventilating and heating, notwithstanding ASHRAE 16 and RAC-1 (incorporated by reference; see § 430. 3).” AHAM supported DOE's proposed amendments to the definition of room air conditioner which are consistent, though not verbatim, with the definitions in AHAM RAC-1-2020. (AHAM, No. 13 at p. 6) 9 DOE did not receive any comment in opposition to the proposed definition. For the reasons provided in the June 2020 NOPR, DOE adopts the definition of “room air conditioner” as proposed. 9 A notation in the form “AHAM, No. 13 at p. 6” identifies a written comment: (1) Made by the Association of Home Appliance Manufacturers; (2) recorded in document number 13 that is filed in the docket of this test procedure rulemaking (Docket No. EERE-2017-BT-TP-0012-0008) and available for review at http://www.regulations.gov; and (3) which appears on page 6 of document number 13. In the June 2020 NOPR, DOE also proposed to further specify the scope of coverage of appendix F by adding a new “Scope” section stating that appendix F contains the test requirements used to measure the energy performance of room ACs. In doing so, DOE would explicitly limit the scope of products tested in accordance with appendix F, and appendix F would be consistent with test procedures for other similar covered products in that it would include an introductory statement of scope. There were no comments pertaining to this addition. DOE adds this new provision to appendix F as proposed. B. Industry Test Standards The DOE room AC test procedure in appendix F references the following two industry standards as the basis of the cooling mode test: ANSI/AHAM RAC-1-2008 and ANSI/ASHRAE Standard 16-2009. ANSI/AHAM RAC-1-2008 provides the specific test conditions and associated tolerances, while ANSI/ASHRAE Standard 16-2009 describes the test setup, instrumentation and procedures used in the DOE test procedure. The cooling capacity, efficiency metric, and other indicators are calculated based on the results obtained through the application of these test methods, as described in appendix F and 10 CFR 430.23(f). Updated versions of AHAM RAC-1 and ANSI/ASHRAE Standard 16 have been released since the publication of the previous DOE test procedure. DOE assessed the updated versions of these standards to determine whether a DOE test procedure that adopted the updated industry standards would produce test results which measure energy efficiency of room ACs during a representative average use cycle without being unduly burdensome to conduct. 1. AHAM RAC-1 The cooling mode test in appendix F is conducted in accordance with the testing conditions, methods, and calculations in Sections 4, 5, 6.1, and 6.5 of ANSI/AHAM RAC-1-2008, as summarized in Table III-1. Table III-1—Summary of ANSI/AHAM RAC-1-2008 Sections Referenced in Appendix F Section Description 4 General test requirements, including power supply and test tolerances. 5 Test conditions and requirements for a standard measurement test. 6.1 Determination of cooling capacity in British thermal units per hour (“Btu/h”). 6.5 Determination of electrical input in watts (“W”). In the June 2020 NOPR, DOE proposed to incorporate by reference ANSI/AHAM RAC-1-2015 but limit the section references in appendix F to cooling mode-specific sections of ANSI/AHAM RAC-1-2015 (by excluding standby mode, off mode, and heating mode sections), and to update the section reference for measuring electrical power input. 85 FR 35700, 35706 (Jun. 11, 2020). ANSI/AHAM RAC-1-2015 introduced new provisions for the measurement of standby mode and off mode power in Section 6.3, as well as the calculations for annual energy consumption and CEER in Sections 6.4 through 6.8. Because those updates do not impact the sections relevant to appendix F, DOE noted in the June 2020 NOPR that it expects that updating the references to ANSI/AHAM RAC-1-2015 in appendix F would not substantively affect test results or test burden. Id. ANSI/AHAM RAC-1-2015 added test requirements and conditions for standby mode and off mode, and heating mode in Sections 4 and 5, respectively. Because the DOE test procedure already addresses standby mode and off mode testing but not heating mode, which is now included in ANSI/AHAM RAC-1-2015, and to avoid confusion regarding the appropriate applicability of ANSI/AHAM RAC-1-2015, DOE proposed in the June 2020 NOPR to update the existing references to Sections 4 and 5 of ANSI/AHAM RAC-1-2008 in appendix F with references to only the cooling mode-specific subsections of ANSI/AHAM RAC-1-2015: Sections 4.1, 4.2, 5.2.1.1, and 5.2.4. Id. DOE also noted in the June 2020 NOPR that the provisions in ANSI/AHAM RAC-1-2015 for measuring electrical power input appear in Section 6.2, rather than Section 6.5 of ANSI/AHAM RAC-1-2008. To reflect this change in section numbers, DOE proposed to update appendix F to reference Section 6.2 of ANSI/AHAM RAC-1-2015 to determine the electrical power input in cooling mode. Id. Since the June 2020 NOPR, AHAM RAC-1 has been updated and the current standard was released in September 2020 as AHAM RAC-1-2020, “Room Air Conditioners” (AHAM RAC-1-2020). Unlike ANSI/AHAM RAC-1-2015, AHAM RAC-1-2020 includes a test method for products with variable-speed compressor units; allows for voluntary testing inside a psychometric chamber; removes the tests for uncommon water-cooled units as well as the sweat, drip, and heating tests; and updates references to the most recent versions of other industry standards—AHAM RAC-1-2020 references ANSI/ASHRAE Standard 16-2016, for reasons outlined below, and IEC Standard 62301 Second Edition for standby power measurement. 10 10 Copies of AHAM RAC-1-2020 can be purchased from the Association of Home Appliance Manufacturers at 1111 19th Street NW, Suite 402, Washington, DC 20036, 202-872-5955, or by going to http://www.aham.org. AHAM and GEA urged DOE to adopt AHAM RAC-1-2020. AHAM commented that this test procedure is identical to the existing test procedure waivers and the test procedure proposed in the June 2020 NOPR. AHAM further commented that uncommon practices such as water-cooled unit testing have been eliminated and tests irrelevant to energy and capacity measurement such as the sweat, drip, and heating tests have been removed from AHAM RAC-1-2015 such that the AHAM RAC-1-2020 procedure is now consistent with the scope of the DOE test procedure. AHAM stated that AHAM RAC-1-2020 does allow for voluntary testing in a psychrometric (air-enthalpy) chamber, which DOE declined to propose for adoption in the June 2020 NOPR. AHAM and GEA further stated that adopting AHAM RAC-1-2020 as the DOE test procedure would not change the substance of DOE's proposed rule unless DOE were to consider allowing voluntary testing in a psychrometric chamber. AHAM asserted that AHAM RAC-1-2020 is not unduly burdensome to conduct and produces results that reflect the energy efficiency of room ACs during a representative average use cycle. (AHAM, Public Meeting Transcript, No. 12 at pp. 9-10, 21; AHAM, No. 13 at p. 2; GEA, No. 18 at p. 1) 11 AHAM further noted that, at the time of the June 2020 NOPR comment period, AHAM RAC-1-2020 had not yet been published. However, in an additional comment submitted on December 18, 2020, AHAM confirmed publication of AHAM RAC-1-2020 and that it is consistent with what AHAM stated it would be in their previous comment. (AHAM, No. 20 at pp. 1-2) 11 A notation in the form “AHAM, Public Meeting Transcript, No. 12 at pp. 9-10, 21” identifies an oral comment that DOE received on August 6, 2020 during the public meeting, and was recorded in the public meeting transcript in the docket for this test procedure rulemaking (Docket No. EERE-2017-BT-TP-0012-0012). This particular notation refers to a comment (1) made by AHAM during the public meeting; (2) recorded in document number 12, which is the public meeting transcript that is filed in the docket of this test procedure rulemaking; and (3) which appears on pages 9 through 10 and 21 of document number 12. Consistent with the comments received, DOE has determined that AHAM RAC-1-2020 generally provides results that are representative of an average use cycle of room ACs, including room ACs that are variable-speed, and is not unduly burdensome to conduct. Therefore, DOE is adopting AHAM RAC-1-2020 as a referenced standard for the DOE room AC test procedure in appendix F, with modifications that DOE has determined are necessary to improve the representativeness and repeatability of the test procedure. The modifications are discussed in further detail in the sections that follow. 2. ANSI/ASHRAE Standard 16 Appendix F previously referenced the 1983 version of ANSI/ASHRAE Standard 16, which was reaffirmed in 2009, for cooling mode temperature conditions, methods, and calculations. In the June 2020 NOPR, DOE proposed to reference sections of ANSI/ASHRAE Standard 16-2016 in appendix F. 85 FR 35700, 35707 (Jun. 11, 2020). In the June 2020 NOPR, DOE stated that ANSI/ASHRAE Standard 16-2016 made a number of updates to the industry standard, including an air-enthalpy test approach as an alternative to the calorimeter approach, heating mode testing, additional clarification on placement of air samplers and thermocouples, stability requirement definitions, and new figures for additional tests and to also improve previous figures. 85 FR 35700, 35706 (Jun. 11, 2020). DOE initially determined, however, that the general cooling mode methodology remains unchanged. Id. The addition of the air-enthalpy approach provides more flexibility in conducting the tests, and the heating mode test is based on the tests previously included in ANSI/ASHRAE Standard 58-1986 “Method of Testing for Rating Room Air Conditioner and Packaged Terminal Air Conditioner Heating Capacity.” In the June 2020 NOPR DOE stated that the general calorimeter test methodology is unchanged in ANSI/ASHRAE Standard 16-2016 and tentatively determined that the additional detail and clarifying updates would improve the repeatability and reproducibility of test results. Id. ANSI/ASHRAE Standard 16-2016 provides best practices for thermocouple and air sampler placement, recognizing that the unique characteristics of each test chamber will result in particular air flow and temperature gradients in the chamber, influenced by the interaction of the reconditioning equipment and the test unit. These practices address the distances for placing the air sampler from the unit discharge points and thermocouple spacing on the air sampling device. Figure 1 and Figure 2 of ANSI/ASHRAE Standard 16 are updated with additional details and references. Section 5 of ANSI/ASHRAE Standard 16-2016 includes additional provisions regarding instrument calibration and accuracy. ANSI/ASHRAE Standard 16-2016 requires measuring data at more frequent intervals to minimize the sensitivity of the final average value to variations in individual data points, resulting in a more repeatable and reproducible test procedure. Based on DOE's experience with testing at various test laboratories, requiring more frequent data measurements will have minimal impact on testing burden because most testing laboratories are already using a data acquisition system that has the capability to take more frequent measurements. In urging DOE to incorporate AHAM RAC-1-2020, AHAM and GEA supported the incorporation of relevant sections of the 2016 version of ANSI/ASHRAE Standard 16, ANSI/ASHRAE Standard 16-2016. In AHAM RAC-1-2020, AHAM adopted the most current industry standards, including ANSI/ASHRAE Standard 16-2016. (AHAM, Public Meeting Transcript, No. 12 at pp. 9-10; AHAM, No. 13 at p. 2; GEA, No. 18 at p. 1) For these reasons provided in the June 2020 NOPR and in this document, and in consideration of the comments received in support of ANSI/ASHRAE Standard 16-2016, DOE is updating appendix F to reference ANSI/ASHRAE Standard 16-2016. ANSI/ASHRAE Standard 16-2016 also updates requirements for the accuracy of instruments. The 2009 reaffirmation of ANSI/ASHRAE Standard 16 requires, in Section 5.4.2, accuracy to ±0.5 percent of the quantity measured for instruments used for measuring all electrical inputs to the calorimeter compartments. ANSI/ASHRAE Standard 16-2016, in Section 5.6.2, no longer broadly includes any inputs and instead includes more specific language ( e.g., it explicitly mentions the power input to the test unit, heaters, and other cooling load contributors). To ensure that the electrical input for all key equipment is properly measured, in the June 2020 NOPR, DOE proposed to maintain the accuracy requirement of ±0.5 percent of the quantity measured for instruments used for measuring all electrical inputs, to the test unit, all reconditioning equipment, and any other equipment that operates within the calorimeter walls. 85 FR 35700, 35707 (Jun. 11, 2020). No comments were received pertaining to this reference. While DOE is incorporating by reference ANSI/ASHRAE Standard 16-2016 generally, DOE maintains that the instrument accuracy of ±0.5 percent of the quantity measured is applicable to all devices measuring electrical input for the room AC test procedure, and not just those explicitly mentioned in ANSI/ASHRAE Standard 16-2016. 3. ANSI/ASHRAE Standards 41.1, 41.2, 41.3, 41.6, and 41.11 ANSI/ASHRAE Standard 16-2016 references industry standards in specifying certain test conditions and measurement procedures. In the June 2020 NOPR, DOE proposed to incorporate those industry standards specified in the relevant sections of ANSI/ASHRAE Standard 16-2016. Specifically, DOE proposed to incorporate by reference: ANSI/ASHRAE Standard 41.1-2013, “Standard Method for Temperature Measurement, as referenced in ANSI/ASHRAE Standard 16-2016 Section 5.1.1 for all temperature measurements except for dew-point temperature; ANSI/ASHRAE Standard 41.2-1987 (RA 1992), “Standard Methods for Laboratory Airflow Measurement,” as referenced in Section 5.5.1 of ANSI/ASHRAE Standard 16-2016 for airflow measurements; ANSI/ASHRAE Standard 41.3-2014, “Standard Methods for Pressure Measurement,” as referenced in Section 5.2.5 of ANSI/ASHRAE Standard 16-2016 for the prescribed use of pressure measurement instruments; ANSI/ASHRAE Standard 41.6-2014, “Standard Method for Humidity Measurement,” as referenced in Section 5.1.2 of ANSI/ASHRAE Standard 16-2016 for measuring dew-point temperatures using hygrometers; and ANSI/ASHRAE Standard 41.11-2014, “Standard Methods for Power Measurement,” as referenced in Section 5.6.4 of ANSI/ASHRAE Standard 16-2016 regarding the use and application of electrical instruments during tests. Incorporating these standards would clarify which versions of the standards are required to conduct tests according to the procedure in appendix F. 85 FR 35700, 35707 (Jun. 11, 2020). DOE received no comments on the proposal to incorporate ANSI/ASHRAE Standard 41.1-2013, ANSI/ASHRAE Standard 41.2-1987 (RA 1992), ANSI/ASHRAE Standard 41.3-2014, ANSI/ASHRAE Standard 41.6-2014, and ANSI/ASHRAE Standard 41.11-2014 in appendix F. DOE is adopting its proposal to incorporate those industry standards appendix F. C. Variable-Speed Room Air Conditioner Test Procedure Historically, room ACs have been designed using a single-speed compressor, which operates at full cooling capacity while the compressor is on. To match the cooling load of the space, which in most cases is less than the full cooling capacity of the compressor, a single-speed compressor cycles on and off. This cycling behavior generally introduces inefficiencies in refrigeration system performance. Variable-speed room ACs became available on the U.S. market in 2018. These models employ an inverter compressor that can reduce its speed to provide continuous cooling that matches the observed cooling load. Accordingly, a variable-speed compressor runs continuously, adjusting its speed up or down as required. In addition to reducing or eliminating cycling inefficiencies, in a variable-speed unit operating at reduced capacity the evaporator and condenser heat exchange effectiveness are improved, since they are handling reduced loads, thereby improving compressor efficiency. The previous DOE test procedure measured the performance of a room AC while operating under a full cooling load; i.e., the compressor is operated continuously in its “on” state. As a result, the DOE test does not capture any inefficiencies due to compressor cycling. Consequently, the efficiency gains that can be achieved by variable-speed room ACs due to the avoidance of cycling losses were not measured by the previous test procedure. In the June 2020 NOPR, DOE presented the results of its investigative testing to quantify the impacts of cycling losses and the relative efficiency benefits of a variable-speed compressor. 85 FR 35700, 35707-35708 (Jun. 11, 2020). DOE compared the performance of two variable-speed room ACs from two different manufacturers, with single-speed room AC of similar capacity from the same manufacturers, under reduced cooling load conditions. 12 DOE installed each room AC in a calorimeter test chamber, set the unit thermostat to 80 degrees Fahrenheit (°F), and applied a range of fixed cooling loads to the indoor chamber. 13 14 The calorimeter chamber conditioning system was configured to apply a fixed cooling load rather than maintaining constant indoor chamber temperature, thereby allowing the test unit to maintain the target indoor chamber temperature by adjusting its cooling operation in response to the changing temperature of the indoor chamber. 15 Figures III-1 and III-2 show the efficiency gains and losses for the range of reduced cooling loads tested for each unit, relative to the performance of each unit as tested using appendix F. 16 12 The first room AC was tested under the 95 °F outdoor test condition (Figure III-1), the second under the 82 °F outdoor test condition (Figure III-2), and the change in EER and load from full-load used for each test was determined based on an appendix F test with the noted outdoor test condition. 13 A cooling load is “applied” by adjusting and fixing the rate of heat added to the indoor test chamber to a level at or below that of the nominal cooling capacity of the test unit. 14 This approach aims to represent a consumer installation in which the amount of heat added to a room may be less than the rated cooling capacity of the room AC ( e.g., electronics or lighting turned off, people or pets leaving the room, and external factors such as heat transfer through walls and windows reducing with outdoor temperature). 15 DOE notes that this test chamber configuration differs from the configuration used in appendix F. Appendix F uses a constant-temperature configuration, in which the indoor chamber temperature is held fixed ( i.e., the indoor temperature does not drop while the room AC is operational). 16 For single-speed room ACs under appendix F, the thermostat is typically set as low as possible to ensure that the unit provides maximum cooling during the cooling mode test period. BILLING CODE 3510-33-P ER29MR21.000 ER29MR21.001 BILLING CODE 3510-33-C In Figures III-1 and III-2, the distance of each data point from the x-axis represents the change in efficiency relative to the full-load efficiency for each unit at the outdoor test condition used. 12 The single-speed room AC efficiency decreases in correlation with a reduction in cooling load, reflecting cycling losses that become relatively larger as the cooling load decreases. In contrast, the efficiency of the variable-speed room AC increases as the cooling load decreases, reflecting the lack of cycling losses and inherent improvements in system efficiency associated with lower-capacity operation. As explained in the June 2020 NOPR, these results demonstrate that the previous test procedure does not account for significant efficiency gains that variable-speed room ACs can achieve under reduced temperature conditions. 85 FR 35700, 35708 (Jun. 11, 2020). 1. Methodology In the June 2020 NOPR, DOE proposed a test method to measure the efficiency gains for variable-speed room ACs that are not captured by the previous DOE test procedure. 85 FR 35700, 35708-35709 (Jun. 11, 2020). DOE based the proposed method on the alternate test procedure required under the LG Waiver and the Midea Waiver, (collectively, “the waivers”) for specified basic models of variable-speed room ACs. 84 FR 20111 (May 8, 2019) and 85 FR 31481 (May 26, 2020). The alternate test procedure proposed in the NOPR, which is substantively consistent with the waivers, is generally consistent with the approach in AHAM RAC-1-2020, as discussed in section III.B.1 of this document. As discussed in this section below, DOE is adopting the AHAM RAC-1-2020 test procedure in this final rule, with some modifications for the purposes of improved representativeness and repeatability, which provides a methodology for obtaining a reported CEER value by adjusting the intermediate CEER value as tested at the 95 °F test condition according to appendix F using a “performance adjustment factor” (“PAF”). Conceptually, the approach for variable-speed room ACs adopted in this final rule involves measuring performance over a range of four test conditions, applying user settings to achieve the full compressor speed at two test conditions and manufacturer-provided instructions to achieve a reduced fixed compressor speed at the other two test conditions, which collectively comprise representative use. These temperature conditions were derived from the DOE test procedure for central air conditioners with variable-speed compressors and include three reduced-temperature test conditions—under which variable-speed room ACs perform more efficiently than single-speed room ACs—and the test condition specified in the previous test procedure. 17 The single-speed room AC test procedure, however, does not factor in the reduced-temperature test conditions under which single-speed units also will perform more efficiently (although not as well as variable-speed room ACs). As a result, comparing variable-speed performance at all test conditions against a single-speed unit at the highest-temperature test condition would not yield a fair comparison. The PAF represents the average relative benefit of variable-speed over single-speed across the whole range of test conditions. It is applied to the measured variable-speed room AC performance only at the high-temperature test condition to provide a comparison to the single-speed CEER metric based on representative use. 17 The central air conditioner test procedure can be found at Title 10 of the CFR part 430, subpart B, appendix M, “Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps.” The steps for determining a variable-speed room AC's PAF are summarized as follows: • Measure the capacity and energy consumption of the sample unit at the single test condition used for single-speed room ACs (95 °F dry-bulb outdoor temperature), with the compressor speed at the maximum (full) speed, achieved using the user settings ( i.e., setpoint) selected in accordance with the appendix F test. • Measure the capacity and energy consumption of the sample unit at three additional test conditions (92 °F, 87 °F, and 82 °F dry-bulb outdoor temperature), 18 with compressor speed at full using the user settings in accordance with appendix F, and fixed at intermediate and minimum (low) speed, respectively. 19 Using theoretically determined adjustment factors, 20 calculate the equivalent performance of a single-speed room AC with the same cooling capacity and electrical power input at the 95 °F dry-bulb outdoor temperature, with no cycling losses ( i.e., a “theoretical comparable single-speed” room AC) for each of the three test conditions. 18 The additional reduced-temperature conditions are described further in section III.C.2 of this document. 19 The fixed compressor speeds are described further in section III.C.3 of this document. 20 These adjustment factors are described further in section III.C.4 of this document. • Calculate the annual energy consumption in cooling mode at each of the four cooling mode test conditions for a variable-speed room AC, as well as for a theoretical comparable single-speed room AC with no cycling losses. This theoretical single-speed room AC would perform the same as the variable-speed test unit at the 95 °F test condition but perform differently at the other test conditions. • Calculate an individual CEER value at each of the four cooling mode test conditions for the variable-speed room AC, as well as for a theoretical comparable single-speed room AC with no cycling losses. • Using cycling loss factors derived from an industry test procedure and DOE test data, 21 calculate an adjusted CEER value at each of the four cooling mode test conditions for a theoretical comparable single-speed room AC, which includes cycling losses. 21 The derivation of these cycling loss factors is described in more detail in section III.C.5 of this document. • Using weighting factors 22 representing the fraction of time spent and cooling load expected at each test condition in representative real-world operation, calculate a weighted-average CEER value (reflecting the weighted-average performance across the four test conditions) for the variable-speed room AC, as well as for a theoretical comparable single-speed room AC. 22 These “fractional temperature bin” weighting factors are described in more detail in section III.C.6 of this document. • Using these weighted-average CEER values for the variable-speed room AC and a theoretical comparable single-speed room AC, calculate the PAF as the percent improvement of the weighted-average CEER value of the variable-speed room AC compared to a theoretical comparable single-speed room AC. 23 This PAF represents the improvement resulting from the implementation of a variable-speed compressor. 23 The performance adjustment factor is described in more detail in section III.C.7 of this document. DOE's approach to addressing the performance improvements associated with variable-speed room ACs is generally consistent with the alternate test procedures required in the waivers and with the test procedure updates proposed in the June 2020 NOPR. 24 The following sections of this document describe each aspect of the approach in greater detail. 24 DOE estimates that the CEER value for a variable-speed room AC determined in accordance with the amendments adopted in this final rule would be about 1.6 percent greater than the CEER value determined in accordance with the June 2020 NOPR proposed test approach, which was consistent with the alternate test procedure prescribed in a Decision and Order granting a waiver from the DOE test procedure for room air conditions to LG Electronics (84 FR 2011; May 8, 2019) and in an Interim Waiver granted to GD Midea Air Conditioning Equipment Co. LTD (84 FR 68159; Dec. 13, 2109). 85 FR 35700, 35709. 2. Test Conditions As discussed previously, variable-speed room ACs provide improved performance at reduced cooling loads by reducing the compressor speed to match the load, thereby improving system efficiency. DOE recognizes that throughout the cooling season, room ACs operate under various outdoor temperature conditions. DOE also asserts that these varying outdoor conditions present a range of reduced cooling loads in the conditioned space, under which a variable-speed room AC would perform more efficiently than a theoretical comparable single-speed room AC. To measure this improved performance, in the June 2020 NOPR, DOE proposed a test procedure for variable-speed room ACs that adds three test conditions (92 °F, 87 °F, and 82 °F dry-bulb outdoor temperatures and 72.5 °F, 69 °F, and 65 °F wet-bulb outdoor temperatures, respectively) to the existing 95 °F test condition, consistent with the test conditions in the waivers. 85 FR 35700, 35709 (Jun. 11, 2020). These temperatures represent potential outdoor temperature conditions between the existing 95 °F test condition and the indoor setpoint of 80 °F. These additional test conditions are also consistent with the representative temperatures for bin numbers 6, 5, and 4 in Table 19 of DOE's test procedure for central air conditioners at appendix M. See id. Rice expressed concern that the temperature range of the proposed test points in the NOPR is too narrow, as they are based on only four of the eight cooling-mode outdoor-temperature bins of the 2017 version of Air-Conditioning, Heating and Refrigeration Institute (“AHRI”) Standard 210/240, (“AHRI Standard 210/240”), “Performance Rating of Unitary Air-conditioning & Air-source Heat Pump Equipment,” and a wider temperature range for testing is needed. Rice commented that the binned loads in AHRI Standard 210/240 were determined for more typical indoor dry-bulb settings, but the analysis in AHRI Standard 210/240 uses 80 °F dry-bulb and 67 °F wet-bulb indoor ratings data. Rice recommended that a more complete range of temperature bins and their associated cooling load hours from AHRI Standard 210/240 should be considered for the CEER analysis. (Rice, No. 17 at pp. 1-2; see also Rice, Preliminary Analysis, 25 No. 25 at p. 2) Rice recommended accounting for the fractional loads and hours of outdoor-temperature bins 67, 72, and 77 °F with a lower temperature test condition with an outdoor dry-bulb temperature of 75 °F be used in place of the 92 °F dry-bulb temperature test condition. Rice asserted that there was not sufficient justification to test at full speed test at 92 °F, as it is close to a full speed test at the 95 °F dry-bulb temperature test condition. Rice recommended that the fractional bin hours of the 92, 97, and 102 °F outdoor-temperature bins should be applied to the 95 °F dry-bulb temperature test condition, which is actually the midpoint temperature of the lower two bins. (Rice, No. 17 at pp. 1-2; see also Rice, Preliminary Analysis, No. 25 at p. 2) 25 The notation “Preliminary Analysis” indicates that the comment is filed in the docket of the Energy Conservation Standards for Room Air Conditioners Preliminary Analysis rulemaking (EERE-2014-BT-STD-0059) and available for review at http://www.regulations.gov. DOE recognizes that the test conditions proposed in the June 2020 NOPR do not encompass the full range of bin temperature in Table 16 of ANSI/AHRI Standard 210/240. The temperature bins in Table 16 of ANSI/AHRI Standard 201/240 apply to central air conditioners, which are fixed appliances, installed year-round, built into homes, and operate based on a central thermostat to maintain a relatively constant temperature throughout the conditioned space. Room ACs are instead, often seasonally, installed in a single room; operate based on an internal thermostat when turned on, typically only during the cooling season; and may be readily turned off when the room is not occupied. Consumers are more acutely aware of a room AC's operation than that of a central air conditioner; as they are used to cool a single room, often only when that room is occupied; make more noise; and are visible in the room. For these reasons, consumers are more likely to rely on a room AC at the higher temperatures in the range of bin temperatures in Table 16 of ANSI/AHRI Standard 210/240, as compared to at the lower temperatures in the bin. At the lower temperatures, consumers using room ACs are more likely than consumers with central air conditioners to open a window or operate the unit with only the fan on to circulate indoor air when cooler outdoor air is available to draw in through a “fresh air” vent, making the lower temperature bins less representative of room AC operation in cooling mode. DOE also notes that the temperature conditions proposed in the June 2020 NOPR are consistent with the industry-accepted test procedure, AHAM RAC-1-2020. For the reasons discussed in this section, DOE is adopting the four temperature conditions for variable-speed room ACs proposed in the June 2020 NOPR. 3. Variable-Speed Compressor Operation The DOE test procedure maintains fixed temperature and humidity conditions in the indoor chamber and requires configuring the test unit settings ( i.e., setpoint and fan speed), to achieve maximum cooling capacity. See Section 3.1 of appendix F, as amended, and Section 6.1.1.4 of ANSI/ASHRAE Standard 16-2016. Under these conditions, units under test may operate continuously at their full cooling capacity, even at the reduced outdoor temperature test conditions described in section III.C.2 of this document, without the compressor cycling (for single-speed units) or compressor speed reduction (for variable-speed units) that would be expected under real-world operation. Therefore, in this final rule, DOE establishes additional test procedure adjustments, beyond reduced outdoor temperature test conditions, to fully capture the energy efficiency of variable variable-speed room ACs at reduced cooling loads. As described previously, in a typical consumer installation, reduced outdoor temperatures would result in reduced indoor cooling loads. A test that would provide constant reduced cooling loads could be considered, but as discussed below in section III.E.1.e of this document, DOE concludes such a test would not be feasible at this time. Instead, in the June 2020 NOPR, DOE proposed adopting a test that requires fixing the variable-speed room AC compressor at particular compressor speeds that would reflect the expected load under each of the four test conditions, as described further in the following sections. 85 FR 35700, 35709 (Jun. 11, 2020). a. Compressor Speeds In the June 2020 NOPR, to ensure the compressor speeds are representative of actual speeds at the expected cooling loads at each of the outdoor test conditions, DOE proposed requiring that the compressor speed of a variable-speed room AC be set to full speed at the two highest outdoor temperature test conditions (based on test A Full at 95 °F and test B Full at 92 °F from Table 8 of AHRI Standard 210/240), at intermediate compressor speed at the 87 °F test condition (based on test E Int ), and at low compressor speed at the 82 °F test condition (based on test D Low ), consistent with the tests and requirements in Table 8 of AHRI Standard 210/240, which specifies representative test conditions and the associated compressor speeds for variable-speed unitary air conditioners. 85 FR 35700, 35709 (Jun. 11, 2020). The California IOUs questioned the representativeness of testing variable-speed room ACs using fixed-speed testing and referenced statements from the 2019 Appliance Standards and Rulemaking Federal Advisory Committee's Variable Refrigerant Flow Working Group that such testing was not representative of field performance, largely because the control settings used during testing did not match the operational behavior of units outside of their test mode. 26 The California IOUs also cited research conducted at the Bundesanstalt für Materialforschung und -prüfung (“BAM”) Federal Institute for Material Research and Testing in Germany, in which all but one of the seven residential mini-split air conditioners with variable-speed equipment that were tested consumed significantly higher energy when consumer-adjustable, built-in controls were used relative to fixed controls ( i.e., controls that set the compressor speed using a manufacturer-provided remote or code). 27 The California IOUs stated that researchers reported many units reverted to on-off (cycling) operation when the outdoor temperatures were between 77 and 86 °F. The California IOUs encouraged DOE to amend the test procedure to improve representativeness and facilitate product comparison with air conditioners tested under appendix M1 28 to 10 CFR part 430. The California IOUs further encouraged DOE, in collaboration with industry and energy efficiency advocates, to update the test procedure for room ACs by requiring the measurement of units at the 95 °F test condition under their native controls to see the speeds at which the compressors operate to ensure accurate testing. (California IOUs, Public Meeting Transcript, No. 12 at pp. 30-33; California IOUs, No. 14 at p. 4) 26 All published documents directly related to the 2019 Appliance Standards and Rulemaking Federal Advisory Committee's Variable Refrigerant Flow Working Group test data are available in docket EERE-2018-BT-STD-0003 ( https://regulations.gov/docket/EERE-2018-BT-STD-0003 ). 27 Palkowski, Carsten & Schwarzenberg, Stefan & Simo, Anne. (2019). “Seasonal cooling performance of air conditioners: The importance of independent test procedures used for MEPS and labels.” International Journal of Refrigeration. 104. 10.1016/j.ijrefrig.2019.05.021. 28 Appendix M is the currently applicable DOE test procedure for central air conditioners and heat pumps. Appendix M1 will become the test procedure mandatory for use for central air conditioners and heat pumps on or after January 1, 2023. Appendix M and appendix M1 contain similar test conditions, so DOE's evaluation of comments relative to appendix M applies equally to appendix M1. DOE notes that the findings of the 2019 Appliance Standards and Rulemaking Federal Advisory Committee's Variable Refrigerant Flow Working Group applied to variable-refrigerant flow multi-split air conditioners and heat pumps, which have different applications and typical use cases from room ACs and which typically provide cooling to multiple locations within a home. Based on a review of the market, room ACs are typically marketed for temporary seasonal installation 29 for the purpose of cooling a single room, 30 whereas multi-split systems are permanent and may be used as part of a larger whole-home cooling system. For these reasons, the comparability of the room AC test procedure and the test procedure for multi-split air conditioners was not further considered in this final rule. 29 Only 14 room AC models on the market have reverse-cycle heating (a heating technology implemented in other electric cooling products intended for year-round operation), compared to the 1,825 total room AC models on the market according to DOE's CCMS database, as accessed February 10, 2021. This indicates that room AC are overwhelmingly used for seasonal cooling. 30 Room air conditioners are typically purchased by selecting cooling capacity to match the size of a single room to be cooled. See, for example, the ENERGY STAR buying guidance at: https://www.energystar.gov/products/heating_cooling/air_conditioning_room . During investigative testing, two variable-speed room AC models from different manufacturers performed differently under fixed temperature conditions with the user settings ( e.g., fan speed, grille position) and thermostat setpoint selected in accordance with the appendix F test (“appendix F setpoint”), relative to the fixed controls, as specified in the waivers and proposed in the June 2020 NOPR. When operating under fixed temperature conditions and the appendix F setpoint ( i.e., the setpoint which resulted in the maximum cooling capacity, per the requirement in ASHRAE 16-2016), one unit was 10 percent more efficient than when using fixed controls at the 95 °F test condition as specified in the waivers. The second unit was 11 percent less efficient when operated under fixed temperature conditions and the appendix F setpoint than when using fixed controls. Based on the observed differences in the room AC performance when using the fixed full compressor speed as compared to the fixed temperature conditions and appendix F setpoint, DOE is requiring the use of fixed chamber temperature conditions with a unit setpoint of 75 °F for the “full speed” test, as use of this test setup improves representativeness and reproducibility of results. While AHAM RAC-1-2020 requires the use of a fixed full compressor speed set in accordance with manufacturer instructions, as described above, DOE is adopting a revised approach in this final rule to improve representativeness and repeatability. Using a constant temperature test with a thermostat setpoint of 75 °F, in place of the fixed “full” compressor speed, will ensure measured performance reflects the expected performance of the unit when using a common setpoint selected in the field at 95 °F and 92 °F outdoor temperatures, where DOE expects these units to be operating at full speed. However, DOE is not requiring the use of fixed temperature conditions, user settings, and thermostat set at 75 °F for the 87 °F and 82 °F outdoor test condition tests, because those tests represent lower cooling load conditions and would require a load-based test to represent expected unit performance at the associated reduced loads without fixing the compressor speed. As discussed in section III.E.1.d of this document, a load-based test is not feasible at this time. Therefore, the reduced outdoor conditions tests are conducted with fixed compressors speeds that are representative of performance at the expected loads at those reduced conditions. The fixed compressor speeds are defined based on the resulting cooling capacity using fixed temperature condition tests and a unit thermostat setpoint at 75 °F, as discussed in section III.D of this document. Therefore, in this final rule, DOE is requiring fixed temperature conditions with a unit thermostat setpoint of 75 °F, rather than using manufacturer instructions to fix the compressor speed for variable-speed room ACs at the 95 °F and 92 °F test conditions, while requiring that the compressor speed be fixed to intermediate speed at the 87 °F test condition and low speed at the 82 °F test condition, as discussed and defined in section III.D.1.b of this document and in Sections 2.15 and 2.16 in appendix F, respectively. b. Instructions for Fixing Compressor Speeds Setting and maintaining a specific compressor speed for a variable-speed room AC is not typically possible without special control instructions from manufacturers. In the June 2020 NOPR, DOE proposed to require that manufacturers provide in their certification reports the control settings for each variable-speed room AC basic model required to achieve the fixed compressor speed for each test condition, consistent with the approach in the waivers. 85 FR 35700, 35709 (Jun. 11, 2020). These include the compressor frequency setpoints at each test condition, instructions necessary to maintain the compressor speeds required for each test condition, and the control settings used for the variable components. Id. DOE received no comments on the proposal. Due to the change to require that user settings be implemented to achieve maximum cooling capacity when testing at the 95 °F and 92 °F test conditions, as discussed in section III.C.3.a of this document, DOE is requiring that the manufacturer provide in the certification reports the control settings to achieve the fixed compressor speed at only the 87 °F and 82 °F test conditions, thus minimizing certification burden on manufacturers. c. Boost Compressor Speed DOE is aware that a variable-speed room AC's full compressor speed may not be its fastest speed. In particular, the fastest compressor speed may be one that is automatically initiated and used for a brief period of time to rapidly reduce the indoor temperature to within typical range of the setpoint. This compressor speed is referred to as “Boost Compressor Speed” in AHRI Standard 210/240 and is defined as a speed faster than full compressor speed, at which the unit will operate to achieve increased capacity. Manufacturers have described boost compressor speed as used for limited periods of time on occasions where the indoor room temperature is far out of normal operating range of the setpoint. Once the indoor room temperature is within the typical operating range of the setpoint, the room AC returns to the “Full Compressor Speed,” as defined in AHRI Standard 210/240. Because of the typical limited duration of boost compressor speed, it would not significantly contribute to annual energy consumption. AHRI Standard 210/240 does not measure boost compressor speed energy use, and in a final rule published on June 8, 2016, DOE declined to include provisions for measuring boost compressor speed energy use in the central air conditioner test procedure. 81 FR 36992, 37029. DOE stated that accurately accounting for boost compressor speed requires more careful consideration of test procedure changes beyond simply allowing the compressor speed to vary for the test conditions required by the previous procedure, and that DOE would consider such revisions in a future rulemaking. Id. Accordingly, DOE did not propose to measure boost compressor speed performance and energy consumption in appendix F in the June 2020 NOPR, because of the minimal expected operating hours in boost compressor mode and the subsequent insignificant impact on annual energy consumption and performance, to harmonize with AHRI Standard 210/240, the industry approach for variable-speed compressor testing, and because DOE has previously opted to forgo including it for other air conditioning products. 85 FR 35700, 35710 (Jun. 11, 2020). AHAM supported DOE's proposal to forgo measuring boost compressor speed for variable-speed room ACs. AHAM commented that boost compressor speed is used for limited periods of time on occasions where the indoor room temperature is far out of normal operating range of the setpoint. AHAM stated that once the indoor temperature is within the typical operating range of the setpoint, the room AC will return to full compressor speed. AHAM asserted that accounting for boost compressor speed would likely not impact annual energy consumption and performance and, thus, additional test burden would not have a corresponding energy savings or consumer benefit. According to AHAM, EPCA does not require testing of every available mode; EPCA only requires testing of the average consumer use cycle, which boost mode is not according to data available. (AHAM, Public Meeting Transcript, No. 12 at p. 53; AHAM, No. 13 at p. 5) The Joint Commenters, the California IOUs, NEAA, and Rice commented in favor of capturing boost compressor speed operation in the test procedure. (ASAP, Public Meeting Transcript, No. 12 at p. 12; Joint Commenters, No. 15 at pp. 2-3; California IOUs, Public Meeting Transcript, No. 12 at pp. 23-24; NEAA, Public Meeting Transcript, No. 12 at pp. 42-48, 56; Rice, No. 17 at p. 3) The California IOUs commented that boost mode operation may be a significant portion of how consumers actually use the product. (California IOUs, Public Meeting Transcript, No. 12 at pp. 23-24) Rice commented that boost compressor capability requires the inverter/motor drives to be oversized to handle the increased torque and power draw, resulting in more performance drop off at lighter loads. Rice stated that this performance drop-off supports why limiting variable-speed rating tests to no lower than 82 °F may preclude future introduction of more efficient variable-speed drive/motor combinations in compressors that have larger performance advantages below 50-percent capacity reduction. Rice commented that boost compressor speed capability not only can result in unnecessary energy use and increased power demand during rapid cooldown but can also penalize unit performance at lower outdoor temperatures where significant amounts of cooling are delivered. Rice further commented that there is no incentive for manufacturers to limit or drop boost compressor speed features from their designs without some performance penalty applied to units with boost operation, especially if the lowest test point remains at the 82 °F test condition with 50 percent of rated capacity loading. Rice suggested provisions might also be included for suitable performance credits for variable-speed units that allow boost mode to be turned off by the homeowner or utility to reduce unnecessary energy use and/or peak demand. (Rice, No. 17 at pp. 2-3) ASAP, NEAA, the Joint Commenters, and Rice encouraged DOE to further investigate the use and timing of boost compressor speed, expressing concern that not testing it may result in excluding a significant component of the energy use of these units. (ASAP, Public Meeting Transcript, No. 12 at p. 12; NEAA, Public Meeting Transcript, No. 12 at pp. 42-48; Joint Commenters, No. 15 at pp. 2-3; Rice, No. 17 at p. 3) Specifically, NEAA recommended that DOE conduct tests to determine the setpoint differential that would cause boost mode to kick in and the difficulty at which that is under normal or extreme operating conditions. (NEAA, Public Meeting Transcript, No. 12 at pp. 42-48) Rice recommended that DOE conduct additional load-based testing to estimate the added energy use and peak demand from boost compressor speed operation from a typical daytime setback, evening setup schedule. 31 (Rice, No. 17 at p. 3) 31 “Setback” typically refers to when the temperature setting on a thermostat is adjusted to a higher temperature for a period of time when the space will not be occupied or won't require as much cooling, and “setup” refers to when the thermostat setpoint is adjusted back to its original setting, at which the desired level of comfort is provided when the conditioned space is occupied. As discussed, boost compressor speed is a temporary period of elevated compressor speed that occurs to quickly reduce the indoor temperature of a room, typically upon startup or after a service interruption. DOE is not aware of any publicly available data on the frequency or duration of boost compressor speed operation in the field. As such, DOE is unable to ensure the representativeness of a test procedure that addresses boost compressor speed operation. Further, in limited investigative testing of boost compressor speeds for two variable-speed room ACs, DOE was not able to induce a compressor speed higher than the full compressor speed, either by increasing the cooling load to greater than 100 percent or by adjusting the temperature setpoint during cooling mode operation. As such, it is unclear what test procedure provisions would be necessary to test boost compressor speed operation, or if there exists a compressor speed greater than that already activated by the settings in appendix F, without being unduly burdensome. Therefore, DOE is not adopting boost compressor speed provisions in appendix F. 4. Capacity and Electrical Power Adjustment Factors In the waivers and proposed June 2020 NOPR approach, a capacity adjustment factor is used to estimate the increased cooling capacity and reduced electrical power draw of a single-speed room AC at lower outdoor temperature conditions, using a linear extrapolation based on the measured capacity and power draw at the 95 °F test condition, respectively. 85 FR 35700, 35711 (Jun. 11, 2020). To determine these two adjustment factors, DOE used the MarkN model 32 to model room AC performance at reduced outdoor temperature conditions. Id. These modeling results suggested linear capacity and electrical power adjustment factors of 0.0099 per °F and 0.0076 per °F, respectively. Id. 32 MarkN is an energy modeling program developed in an ECS direct final rule for room ACs that DOE published on April 21, 2011. 76 FR 22454. The MarkN program is an update of an adaptation to the Oak Ridge National Laboratory Mark III Heat Pump program for modeling room AC cooling performance. To confirm the validity of these modeled adjustment factors, DOE tested a sample of 14 single-speed room ACs at a range of reduced outdoor temperature test conditions (92 °F, 87 °F, and 82 °F) and compared the predicted values of cooling capacity and electrical power with the measured values at each test condition. The results generally indicated close agreement ( i.e., less than 5 percent difference on average) between the modeled cooling capacity (based on an adjustment factor of 0.0099 per °F) and the measured capacity at each test condition, and between the modeled electrical power draw (based on an adjustment factor of 0.0076 per °F) and the measured electrical power draw at each test condition. DOE tentatively determined that the average difference of less than 5 percent between the modeled values and the experimental values confirmed the validity of these modeled adjustment factors. Therefore, in the June 2020 NOPR, DOE proposed to use the modeled adjustment factors of 0.0099 per °F and 0.0076 per °F for capacity and electrical power, respectively, to calculate the theoretical comparable single-speed room AC performance at reduced outdoor temperature test conditions. 85 FR 35700, 35711 (Jun. 11, 2020). NEAA expressed concern about DOE's proposal to use linear capacity and electrical power adjustment factors to predict the capacity of fixed speed equipment at lower outdoor temperatures. NEAA commented that, while the order of magnitude of the error is small, the factors chosen consistently overpredict capacity and underpredict energy use for single-speed equipment. NEAA further commented that this will reduce the CEER ratings of variable-speed room ACs. NEAA recommended modifying the capacity and electrical power adjustment factors so that they do not overpredict capacity and underpredict energy use consistently. (NEAA, No. 16 at p. 5) DOE disagrees with NEAA's assessment that the modeling factors consistently overpredict capacity and underpredict energy use. DOE observed that the modeling factors were able to predict capacity and energy use in the test sample within four percent on average, and often more accurately. Additionally, there was no consistent trend in the variation in capacity or energy use predictions ( i.e., some predictions were higher than the actual, some were lower). Therefore, DOE is adopting as proposed the capacity and electrical power adjustment factors of 0.0099 per °F and 0.0076 per °F, respectively. 5. Cycling Loss Factors In the June 2020 NOPR, to represent the cycling losses of a theoretical comparable single-speed room AC at reduced outdoor temperature test conditions and expected reduced cooling loads, DOE identified cycling loss factors (“CLFs”) to apply to the interim CEER values at each of the four cooling mode test conditions for a theoretical comparable single-speed room AC. 85 FR 35700, 35711 (Jun. 11, 2020). Table III-4 shows the CLFs for each of the four test conditions. Table III-4—June 2020 NOPR Proposed Cycling Loss Factors Test condition Evaporator inlet air, °F Dry bulb Wet bulb Condenser inlet air, °F Dry bulb Wet bulb Cycling loss factor Test Condition 1 80 67 95 75 1.0 Test Condition 2 80 67 92 72.5 0.971 Test Condition 3 80 67 87 69 0.923 Test Condition 4 80 67 82 65 0.875 These CLFs were based on the default cooling degradation coefficient (“Cd”) in Section 11.2 of AHRI Standard 210/240. The CLF at the 82 °F test condition for a theoretical comparable single-speed room AC is consistent with the default Cd of 0.25, which corresponds to a part-load (cycling loss) factor of 0.875, as determined in Section 11.2 of AHRI Standard 210/240. The remaining CLFs for the other test conditions are consistent with linear interpolation between the CLF of 0.875 at the 82 °F test condition and the CLF of 1.0 at the 95 °F test condition, at which no cycling is expected. Thus, DOE proposed to implement CLFs consistent with the default Cd in AHRI Standard 210/240, to represent the expected performance of a theoretical comparable single-speed room AC at reduced outdoor temperature test conditions. Id. AHAM commented that while DOE cited Section 11.2 of AHRI Standard 210/240 and a Cd of 0.25, AHRI Standard 210/240 includes a Cd of 0.20 for Single Stage Systems in Section 6.1.3.1.1. AHAM recommended that DOE ensure it uses the most recent version of the standard and the correct Cd. (AHAM, No. 13 at p. 5) The California IOUs, NEAA, and Rice expressed concern about the proposed default Cd of 0.25. (California IOUs, Public Meeting Transcript, No. 12 at p. 30; NEAA, No. 16 at p. 5; Rice, No. 17 at pp. 3-4) NEAA commented that room ACs may cycle more than central air conditioners due to improper sizing, further pointing to a need for additional testing. (NEAA, No. 16 at p. 5) Rice commented that Figure III.1 in the June 2020 NOPR suggested that the Cd for the load-tested room AC unit could be as high as 0.42, based on the 21-percent performance loss observed at 50-percent load; this compared with the 12.5-percent loss assumed at 50-percent load with the default Cd assumption. (Rice, No. 17 at pp. 3-4) The California IOUs and Rice recommended DOE conduct additional investigative load-based testing on single-speed room ACs to better estimate the Cd at the 82 °F test condition. (California IOUs, Public Meeting Transcript, No. 12 at p. 30; Rice, No. 17 at pp. 3-4) Rice also commented that a room AC unit is unlikely to be sized exactly to match the room load at 95 °F outdoor ambient conditions. Rice further commented that a minimal 10-percent oversizing, equivalent to that assumed in AHRI Standard 210/240 for unitary ACs, would be more appropriate and would also provide a common basis with current AC ratings practice. Rice stated that use of 110-percent sizing would also provide an appropriate performance benefit, estimated to be approximately 3 percent, to variable-speed room ACs relative to single-speed units. Accordingly, Rice recommended that the assumption of exact sizing be modified to at least be consistent with 110-percent sizing as assumed in AHRI Standard 210/240 for unitary air conditioners. With 110-percent sizing, Rice noted that the default CLFs at 95, 87, and 82 °F would need to be adjusted to 0.977, 0904, and 0.864, respectively, for a Cd of 0.25. Rice also noted that they would need further adjustment if a different default Cd were selected or if the slope of the default single-speed capacity curve was changed. As for the proposed 75 °F test point, Rice commented that the CLFs with a 0.25 Cd are 0.820 at 100-percent sizing and 0.813 at 110-percent sizing. (Rice, No. 19 at p. 6; see also Rice, Preliminary Analysis, No. 25 at pp. 1-2) DOE disagrees with Rice's claim that it is unlikely that room ACs are sized to match room cooling load at a 95 °F outdoor temperature test condition. Room ACs are intended to cool a single room, where the cooling load is more likely to remain steady or within a smaller range. DOE is not aware of any data showing that room ACs are typically oversized. Given the application of room ACs to a more limited space, DOE has determined that it is reasonable to assume that room ACs are sized to match room cooling loads at a 95 °F outdoor temperature test condition. DOE acknowledges the concerns regarding the Cd as proposed in the June 2020 NOPR. In response, DOE conducted additional testing in support of this final rule to determine whether the AHRI Standard 210/240 single-stage Cd of 0.2 suggested by AHAM or a higher value such as 0.42 as suggested by the California IOUs, NEAA, and Rice would be more appropriate. DOE conducted load-based testing on two single-speed room ACs with cooling capacities comparable to variable-speed room ACs of the same brand/manufacturer currently on the market using an outdoor temperature of 82 °F and cooling loads between 47 and 57 percent of the full load, with a target of 52 percent ( i.e., the center of the acceptable range specified in the low compressor speed definition). DOE did not consider cycling losses at an outdoor temperature of 75 °F, based on the decision to not include testing at that temperature condition, as discussed in section III.C.2 of this document. The results of this testing are summarized in Table III-5. Table III-5—Cycling Loss Factors Unit Load % Cd Unit 1 52 0.42 Unit 2 49 0.39 54 0.30 * 52 0.34 * Due to difficulties in achieving the target load percentage of 52% for Unit 2, data for the nearest higher and lower data points were interpolated to estimate the expected Cd at a 52% load. On average, the two single-speed room ACs had a Cd of 0.38 at the 82 °F test condition and 52 percent cooling load, which is relatively close to the maximum Cd value of 0.42 suggested by Rice. Based on DOE's test data, use of a Cd of 0.38 would increase a variable-speed room AC's measured CEER by approximately 5.5 percent. Based on this testing, DOE is adopting a Cd of 0.38, resulting in a CLF at the 82 °F test condition of 0.81. Interpolating between the 82 °F test condition and CLF of 0.81 and 95 °F test condition and CLF of 1, results in a CLF of 0.883 for the 87 °F test condition and a CLF of 0.956 for the 92 °F test condition. 6. Test Condition Weighting Factors In the approach proposed in the June 2020 NOPR, the four interim CEER values representing each of the four cooling mode test conditions were combined, using four weighting factors, into a single weighted-average CEER value. 85 FR 35700, 35711-35712 (Jun. 11, 2020). The resulting weighted-average CEER value represented the weighted-average performance across the range of outdoor test conditions. Id. DOE calculated weighting factors based on the fractional temperature bin hours in Table 19 of DOE's test procedure for central air conditioners at appendix M. DOE identified the fractional temperature bin hours representing the four test conditions in the proposed approach and normalized these four values from appendix M so that they sum to 1.00. Table III-6 shows the June 2020 NOPR weighting factors for each of the four test conditions. Table III-6—June 2020 NOPR Proposed Temperature Condition Weighting Factors Test condition Evaporator inlet air, °F Dry bulb Wet bulb Condenser inlet air, °F Dry bulb Wet bulb CEER weighting factor Test Condition 1 80 67 95 75 0.05 Test Condition 2 80 67 92 72.5 0.16 Test Condition 3 80 67 87 69 0.31 Test Condition 4 80 67 82 65 0.48 AHAM generally agreed with the waivers, which included the weighting factors above. (AHAM, No. 13 at p. 4) ASAP, the Joint Commenters, and Rice expressed concern that DOE's proposed approach would not reflect seasonal efficiency, claiming it would result in underweighting performance at the higher outdoor temperature conditions and overweighting performance at the lower temperature conditions. ASAP commented that, under the weighted-average calculation proposed in the June 2020 NOPR delivered cooling from an hour of operation under the 95 °F test condition was equal to that under the 82 °F test condition, even though the delivered cooling, and energy consumption, at the 95 °F test condition is greater. (ASAP, Public Meeting Transcript, No. 12 at pp. 35-36) Rice suggested replacing the proposed performance weighting factors based on fractional bin hours with fractional delivered cooling output per bin because the proposed approach ignores that, at the lower ambient temperature bins, the delivered amount of cooling is proportionally lower (~50 percent at 82 °F ambient). Rice also recommended replacing the 92 °F test condition with a 75 °F test condition, to supplement the 82, 87, and 95 °F variable-speed ratings tests, to represent the missing ~40 percent of cooling load, as discussed in section III.C.2 of this document. For the proposed 75 °F test condition, Rice stated the variable-speed unit should be run at a reduced speed level to obtain ~30 percent of rated capacity at 95 °F ambient temperature. Rice expressed further concern that PAFs based on the wrong weighting factors and an inappropriately narrowed cooling range will give too much credit to variable-speed designs that operate best in this narrowed range, and may inadvertently favor variable-speed designs that seek ratings advantage by boosting performance at the 82 °F and higher test conditions at the expense of lower ambient temperature performance. (Joint Commenters, No. 15 at p. 2; Rice, No. 17 at pp. 1-2) DOE agrees that the cooling delivered by room ACs at lower outdoor temperature test conditions is proportionally lower than at the appendix F single-speed test condition. Thus, calculating the test condition weighting factors using fractional delivered cooling output per temperature bin, as suggested by Rice, applied to the set of test conditions required by DOE above, would improve the representativeness of the test procedure. This change would not increase the testing burden as compared to the test procedure required under the waivers. While this change would diverge from the industry-accepted test procedure AHAM RAC-1-2020, the deviation is justified due to the improvements in representativeness of the test procedure. Therefore, DOE is adopting the test condition weighting factors shown in Table III-7, calculated by adjusting the weighting factors in Table III-6 by the expected cooling load at each condition based on the building load calculation in AHRI Standard 210/240 (Equation 11.60), and normalizing the resulting values so the final weighting factors sum to 1.0. Table III-7—Final Rule Temperature Condition Weighting Factors Test condition Evaporator inlet air, °F Dry bulb Wet bulb Condenser inlet air, °F Dry bulb Wet bulb CEER weighting factor Test Condition 1 80 67 95 75 0.08 Test Condition 2 80 67 92 72.5 0.20 Test Condition 3 80 67 87 69 0.33 Test Condition 4 80 67 82 65 0.39 7. Weighted CEER and Performance Adjustment Factor The final step in the waivers and the June 2020 NOPR proposed approach is to calculate the PAF, representing the improvement over a theoretical comparable single-speed room AC resulting from the implementation of a variable-speed compressor. 84 FR 20111 (May 8, 2019); 85 FR 31481 (May 26, 2020); 85 FR 35700, 35712 (Jun. 11, 2020). The PAF is calculated as the percent improvement of the weighted-average CEER value of the variable-speed room AC compared to the weighted-average CEER value of a theoretical comparable single-speed room AC under the four defined test conditions. After calculating the PAF, it is added to one and the sum is multiplied by the CEER value of the variable-speed unit when tested at the 95 °F test condition according to appendix F, resulting in the final CEER metric for the variable-speed room AC. By adjusting the variable-speed room AC CEER values to be comparable to single-speed room AC CEER values, DOE expects that consumers will have the information they need to understand the relative efficiency of both types of room AC. In the June 2020 NOPR, DOE proposed calculations to determine a PAF, which would adjust the CEER of a variable-speed room AC to appropriately account for its efficiency improvements relative to a theoretical comparable single-speed room AC under varying operating conditions. 85 FR 35700, 35712 (Jun. 11, 2020). Rice proposed a new method to calculate the weighted average CEER in which the individual weighting factors are divided by the tested CEER values, summed, and the reciprocal of the sum is the weighted CEER value. Rice noted that the result of this formulation exactly matches the result of the conventional binned method from AHRI 210/240. (Rice, No. 19 at pp. 3-4) Rice provided little explanation or evidence supporting this new calculation approach and whether it provides more representative results than the approach proposed in the June 2020 NOPR, beyond indicating the result matches that of the binned method in AHRI 210/240. DOE notes that the calculation approach prescribed in the waivers and proposed in the June 2020 NOPR is the same approach specified in the AHAM RAC-1-2020, which is the latest version of the industry standard specific to room ACs. Therefore, DOE is adopting the PAF and weighted CEER calculations proposed in the June 2020 NOPR that align with AHAM RAC-1-2020 and the waivers granted to date. 8. Air-Enthalpy Test Alternative DOE recognized the additional test burden associated with testing variable-speed room ACs at multiple test conditions as proposed. In an effort to minimize that additional test burden, DOE initially provided for an optional test in the interim waiver granted to LG that allowed for use of the air-enthalpy method. 83 FR 30717 (Jun. 29, 2018; “LG Interim Waiver”). Following the publication of the LG Interim Waiver, DOE conducted investigative testing to further analyze the air-enthalpy method and its suitability for testing room ACs. This testing demonstrated that this method produced unrepresentative and inconsistent results and remedying these deficiencies likely would be unduly burdensome. See 84 FR 20111, 20117. (May 8, 2019) In addition, the air-enthalpy method does not measure any heat transfer within and through the unit chassis, while the calorimeter test does. See Id. Because of the unrepresentative and inconsistent results obtained with the air-enthalpy test equipment that testing laboratories are likely to already own, as well as the higher cost and limited availability of equipment that would be necessary to obtain consistent results for all room ACs of differing airflow rates, DOE contended that the air-enthalpy test method would be unduly burdensome for testing laboratories to implement for room ACs at this time. DOE further noted that, in the waivers granted since the publication of the LG Interim Waiver, DOE did not allow the air-enthalpy test method as an alternative to the calorimeter test method due to the concerns outlined above. 84 FR 20111, 20117 (May 8, 2019), 84 FR 68159, 68162 (Dec. 13, 2019). In the June 2020 NOPR, DOE did not propose to include an optional alternative air-enthalpy test method for variable-speed room ACs in appendix F. 85 FR 35700, 35712 (Jun. 11, 2020). The California IOUs supported DOE's proposal to exclude the air-enthalpy test from the room AC test procedure. The California IOUs commented that DOE's testing demonstrated that this method was unrepresentative and inconsistent, and remedying those deficiencies would be unduly burdensome. (California IOUs, No. 14 at pp. 5-6) For the reasons discussed in the preceding paragraphs and in the June 2020 NOPR, DOE is not adopting the air-enthalpy test method for the testing of variable-speed room ACs in this final rule. 9. Product Specific Reporting Provisions As described, the amendments to appendix F to test variable-speed room ACs at multiple cooling mode test conditions will require the use of fixed temperature conditions with a unit thermostat setpoint of 75 °F, using the same specifications for single-speed room AC controls given in appendix F, rather than using the manufacturer instructions to fix the compressor speed for variable-speed room ACs at the 95 °F and 92 °F test conditions. The amendments to appendix F will also require the compressor speed to be fixed to intermediate speed at the 87 °F test condition and low speed at the 82 °F test condition, as discussed and defined in section III.D.1.b of this document and in Sections 2.15 and 2.16, respectively, in appendix F. In the June 2020 NOPR, to ensure test reproducibility, DOE proposed requiring in 10 CFR 429.15 that manufacturers provide DOE all necessary instructions to maintain the compressor speeds required for each test condition for a variable-speed basic model, as additional product-specific information pursuant to 10 CFR 429.12 (b)(13). 85 FR 35700, 35713 (Jun. 11, 2020). DOE expected that this requirement would add a de minimis incremental burden to the existing reporting requirements. Id. DOE received no comments on this proposal. DOE is including in 10 CFR 429.15 reporting requirements for compressor frequencies and control settings at the 87 °F and 82 °F test conditions as additional product-specific information for certification of each variable-speed room AC basic model. Note that, unlike the proposal in the June 2020 NOPR, DOE is not requiring reporting of the compressor frequency and control settings as additional product-specific information for certification for the 95 °F and 92 °F test conditions for variable-speed units, as discussed in section III.C.3 of this final rule. Manufacturers may request treatment of reported material as confidential business information pursuant to the regulations at 10 CFR 1004.11. 10. Estimated Annual Operating Cost Calculation In the June 2020 NOPR, in conjunction with the amendments for testing variable-speed room ACs, DOE proposed corresponding amendments to the calculation that provides the basis of the annual energy consumption and operating cost information presented to consumers on the EnergyGuide Label. 85 FR 35700, 35713 (Jun. 11, 2020). These changes would allow for an appropriate comparison of the annual energy consumption and operating costs between single-speed room ACs and variable-speed room ACs. As such, in the June 2020 NOPR, DOE proposed that for variable-speed room ACs, the average annual energy consumption used in calculating the estimated annual operating cost in 10 CFR 430.23(f) would be a weighted average of the annual energy consumption at each of the four test conditions in newly added Table 1 of appendix F and the annual energy consumption in inactive mode or off mode. Id. DOE provided, however, that the electrical power input reported for variable-speed room ACs for purposes of certification in 10 CFR 429.15(b)(2) would be the value measured at the 95 °F rating condition, to maintain consistency with the cooling capacity measured at the same condition. Id. The California IOUs asserted that the proposed methods for calculating the annual operating costs will create market confusion, mainly because the variable-speed annual operating energy consumption would be based on a weighted average that includes and heavily weights conditions at which the unit provides less cooling, whereas the average annual energy consumption of a single-speed unit would continue to be based on the 95 °F condition, at which the unit provides more cooling and thus consumes more energy. The California IOUs stated that using different test procedures and energy consumption calculations for different equipment that provide the same consumer utility, in this case, space conditioning, has the potential to create market distortions. (California IOUs, No. 14 at p. 2) Conceptually, variable-speed room ACs and single-speed room ACs both deliver the same amount of cooling to a room, albeit in different ways. The variable-speed room AC provides constant cooling at a reduced rate, while the single-speed room AC switches on to provide maximum cooling for a period of time before switching off and providing no cooling until the temperature in the room rises again. In both cases, the total amount of cooling provided to the room remains the same, only the power consumed by the unit to provide the cooling is different. Furthermore, the test procedure adopted in this final rule assesses the improved efficiency associated with variable-speed room ACs relative to single-speed room ACs, on the basis of adjusted operation at varying, reduced-temperature operating conditions and accounting for reduced energy use associated with eliminating cycling losses. This approach of factoring in reduced-temperature operation over the varying load conditions during the operating hours of the cooling season is thus appropriate for variable-speed units but not for single-speed units. For the reasons discussed above, as proposed in the June 2020 NOPR, DOE is requiring that the average annual energy consumption used in calculating the estimated annual operating cost of variable-speed room ACs in 10 CFR 430.23(f) be a weighted average of the annual energy consumption at each of the four test conditions in newly added Table 1 of appendix F and the annual energy consumption in inactive mode or off mode, to reflect a realistic measure of energy use and operating costs in a representative average use cycle. Additionally, as proposed in the June 2020 NOPR, DOE is defining the electrical power input reported for variable-speed room ACs for purposes of certification in 10 CFR 429.15(b)(2) to be the value measured at the 95 °F rating condition, to maintain consistency with the cooling capacity measured at the same condition, and to provide consumers with the cooling capacity and power input expected at full load conditions. D. Definitions In the June 2020 NOPR, DOE proposed adding a number of definitions to appendix F to accompany the amendments made in this final rule. None of these definitions modified the scope of covered products. 85 FR 35700, 35713 (Jun. 11, 2020). The following section describes each definition in detail. 1. Key Terms In the June 2020 NOPR, DOE proposed definitions for three key terms that appeared in appendix F but have no definitions: Cooling mode, cooling capacity, and combined energy efficiency ratio. 85 FR 35700, 35713 (Jun. 11, 2020). Although room ACs may sometimes operate in other modes as discussed further in section III.E of this final rule, the room AC CEER metric determined in appendix F was based primarily on performance in cooling mode, and several of the amendments also reference “cooling mode.” Therefore, DOE proposed the following definitions for cooling mode, cooling capacity, and combined energy efficiency ratio in appendix F: “Cooling mode” means an active mode in which a room air conditioner has activated the main cooling function according to the thermostat or temperature sensor signal or switch (including remote control). “Cooling capacity” means the amount of cooling, in Btu/h, provided to an indoor conditioned space, determined in Section 4.1 of appendix F. “Combined energy efficiency ratio” means the energy efficiency of a room air conditioner as measured in Btu/Wh and determined in Section 5.2.2 of appendix F for single-speed room air conditioners and Section 5.3.12 of appendix F for variable-speed room air conditioners. Id. To support the amendments pertaining to variable-speed basic models, in the June 2020 NOPR, DOE proposed defining single-speed and variable-speed room ACs as follows: “Single-speed room air conditioner” means a type of room air conditioner that cannot automatically adjust the compressor speed based on detected conditions. “Variable-speed room air conditioner” means a type of room air conditioner that can automatically adjust compressor speed based on detected conditions. 85 FR 35700, 35714 (Jun. 11, 2020). AHAM supported DOE's proposal to add these new definitions in appendix F. (AHAM, No. 13 at p. 6) For the reasons discussed in the June 2020 NOPR, DOE is adopting these new definitions in appendix F. 2. Compressor Speeds In the June 2020 NOPR, DOE also proposed defining the three compressor speeds required for variable-speed testing. 85 FR 35700, 35714 (Jun. 11, 2020). DOE referred to these compressor speeds as “full,” “intermediate,” and “low” based on the test procedure terminology of AHRI Standard 210/240, and were proposed as follows: “Full compressor speed (full)” means the compressor speed at which the unit operates at full load test conditions, achieved by following the instructions certified by the manufacturer. “Intermediate compressor speed (intermediate)” means a compressor speed higher than the low compressor speed by one third of the difference between low compressor speed and full compressor speed with a tolerance of plus 5 percent (designs with non-discrete speed stages) or the next highest inverter frequency step (designs with discrete speed steps), achieved by following the instructions certified by the manufacturer. “Low compressor speed (low)” means the compressor speed at which the unit operates at low load test conditions, achieved by following the instructions certified by the manufacturer, such that Capacity 4 , the measured cooling capacity at test condition 4 in Table 1 of appendix F, is not less than 47 percent and not greater than 57 percent of Capacity 1 , the measured cooling capacity with the full compressor speed at test condition 1 in Table 1 of appendix F. 33 Id. 33 Further information about the acceptable range of delivered cooling at the low compressor speed and lowest test condition, and how they were derived, can be found in the June 2020 TP NOPR. 85 FR 35700, 35714. AHAM generally agreed with the waivers, which included the proposed 10-percent range and 57-percent cooling load as its upper bound above. (AHAM, No. 13 at p. 6) The Joint Commenters, NEAA, and the California IOUs urged DOE to ensure that the proposed fixed compressor speeds are representative of real-world operation. The Joint Commenters, NEAA, and the California IOUs expressed concern that the proposed definition for low compressor speed could lead to measured efficiency values that are not representative. NEAA and the California IOUs pointed to the potential that energy values can subsequently be better than the unit can actually produce in the real world under conditions of less than 95 °F, allowing manufacturers to “game” efficiency ratings as a unit may run differently if its full-load speed does not match how the unit runs in the real world under 95 °F outdoor conditions. Thus, NEAA and the California IOUs suggested that DOE perform additional investigative testing under the 95 °F test condition under native controls and reference variable refrigerant flow air conditioning test procedures regarding whether speed represents use. (NEAA, Public Meeting Transcript, No. 12 at pp. 37-42; California IOUs, Public Meeting Transcript, No. 12 at pp. 30-33; California IOUs, No. 14 at p. 4) Similarly, the Joint Commenters asserted that, under DOE's proposal, manufacturers may have an incentive to test at the 82 °F condition at the compressor speed that provides a cooling capacity as close as possible to 47 percent of the full-load capacity since efficiency typically increases at lower compressor speeds. The Joint Commenters stated that providing 47 percent of the full-load cooling capacity would not meet the cooling load at 82 °F, and that a low compressor speed lower than the operating speed in the field could also result in the intermediate compressor speed being artificially low. The Joint Commenters noted that a variable-speed unit that cannot provide 57 percent of the full-load cooling capacity cannot in fact “match” the representative cooling load at the 82 °F condition. The Joint Commenters stated the test procedure should reflect the potential efficiency gains of variable-speed units that can vary their speed continuously (or in smaller discrete steps) relative to units with compressors with larger discrete steps. (Joint Commenters, No. 15 at pp. 1-2) As discussed in section III.D of the June 2020 NOPR, the 10-percent range allows for discrete variable-speed compressor stages while maintaining the representativeness of the test procedure. While a variable-speed room AC that cannot operate at precisely 57 percent of the full-load cooling capacity cannot exactly match the cooling load at the 82 °F test condition, it could compensate for this in real world operation at an 82 °F outdoor temperature by operating at a lower compressor speed and moving to a higher compressor speed if the room becomes too hot. DOE observed variable-speed compressors with this behavior during load-based testing, though noted that the compressor speed adjustments did not occur frequently, resulting in extended periods of operation at a single compressor speed. Furthermore, the difference in power consumption between the two speeds observed in these scenarios was only about 5% of the full load operating power, and therefore this style of operation would still result in more efficient operation compared to cycling a single-speed compressor on and off to maintain the reduced load. These variable-speed units still provide significant energy savings, so it is important to account for this sort of variable-speed compressor behavior and ensure the test procedure is applicable to even those variable-speed room ACs that have discrete compressor speed steps that may not provide exactly 57 percent of the full-load cooling capacity. DOE further notes that requiring a low compressor speed that results in a single loading percentage ( i.e., 57 percent of the full-load cooling capacity) with no tolerance could greatly increase design and manufacturing burden, and thus may disincentivize the adoption of more efficient technology being newly introduced for room ACs. A 10-percent range would allow for the various types of variable-speed compressors ( i.e., discrete and non-discrete), avoid significant burden on manufacturers, and avoid disincentivizing the adoption of this technology. An upper compressor speed limit of 57 percent of the full-load cooling capacity would ensure that the unit does not cycle on and off under the cooling load expected at an outdoor temperature of 82 °F, which would negate much of the efficiency benefits relative to single-speed room ACs). Therefore, DOE proposed a lower limit of 47 percent to maintain the desired 10-percent range of cooling loads while setting 57 percent of the full-load cooling capacity as the upper limit. In this final rule, DOE is revising the definition of “full compressor speed” proposed in the June 2020 NOPR, to account for the new requirements discussed in section III.C.3.a ( i.e., to require that user settings be implemented to achieve maximum cooling capacity when testing using full compressor speed, rather than fixing the compressor speed using instructions provided by the manufacturer). Furthermore, DOE is also revising the “intermediate compressor speed” definition proposed in the June 2020 NOPR, to clarify that the intermediate compressor speed is defined based on the measured capacity at the 95 °F and 82 °F test condition, using the full and low compressor speeds, respectively. Thus, DOE is adopting its proposals from the June 2020 NOPR, as detailed below. In summary, DOE defines the following in newly added Sections 2.14, 2.15, and 2.16 of appendix F: “Full compressor speed (full)” means the compressor speed at which the unit operates at full load test conditions, achieved by using user settings to achieve maximum cooling capacity, according to the instructions in ANSI/ASHRAE Standard 16-2016 Section 6.1.1.4. “Intermediate compressor speed (intermediate)” means a compressor speed higher than the low compressor speed at which the measured capacity is higher than the capacity at low compressor speed by one third of the difference between Capacity 4 , the measured cooling capacity at test condition 4 in Table 1 of this appendix, and Capacity 1 , the measured cooling capacity with the full compressor speed at test condition 1 in Table 1 of this appendix, with a tolerance of plus 5 percent (designs with non-discrete speed stages) or the next highest inverter frequency step (designs with discrete speed steps), achieved by following the instructions certified by the manufacturer. “Low compressor speed (low)” as the compressor speed specified by the manufacturer at which the unit operates at low load test conditions, such that Capacity 4 , the measured cooling capacity at test condition 4 in Table 1 of this appendix, is no less than 47 percent and no greater than 57 percent of Capacity 1 , the measured cooling capacity with the full compressor speed test condition 1 in Table 1 of this appendix. E. Active Mode Testing The following sections describe amendments and other considerations regarding the active mode testing provisions of appendix F. 1. Cooling Mode The DOE room AC test procedure uses a calorimeter test method to determine the cooling capacity and associated electrical power input of a room AC. See Sections 3.1 and 4.1 of appendix F, as amended. Under this approach, the test unit is installed between two chambers, one representing the indoor side and the other representing the outdoor side, which are both maintained at constant conditions by reconditioning equipment. The room AC operates in cooling mode, transferring heat from the indoor side to the outdoor side, while the reconditioning equipment counteracts the effects of the room AC to maintain constant test chamber conditions. The room AC cooling capacity is determined by measuring the required energy inputs to the reconditioning equipment. a. Test Setup and Air Sampling In the June 2020 NOPR, DOE discussed concerns about whether the measured calorimeter chamber temperature reading is representative of conditions at the test unit condenser and evaporator inlet, which may be affected by recirculation from the condenser and evaporator exhaust, respectively, thereby potentially reducing test repeatability and reproducibility. 85 FR 35700, 35715 (Jun. 11, 2020). DOE noted that the size, capability, and orientation of components within calorimeter test chambers may vary significantly, and that third-party laboratories extensively analyze their chambers and testing apparatus to maintain consistent and accurate air sampling measurements. DOE also understood that temperature gradients and unique airflow patterns can result from the interaction of a chamber reconditioning apparatus and the room AC under test, and that these interactions are particular to and dependent upon factors such as chamber size and shape, chamber equipment arrangement, size of reconditioning apparatus, and others, as noted in ANSI/ASHRAE Standard 16-2016 Section 8.2.7. Therefore, in the June 2020 NOPR, DOE contended that universal requirements for air sampling instrumentation and thermocouple placement could potentially reduce test accuracy and reproducibility. As discussed in section III.B.2 of this document, DOE proposed to update the reference to ANSI/ASHRAE Standard 16 to the most current 2016 version, which includes additional clarification on best practices for air sampler and thermocouple placement. Id. DOE received no comments on the test setup and air sampling discussion and proposals from the June 2020 NOPR. For the reasons discussed in the preceding paragraph, DOE is updating the reference to ANSI/ASHRAE Standard 16 to the most current 2016 version, which includes additional clarification on best practices for air sampler and thermocouple placement. b. Air-Enthalpy Test In the June 2020 NOPR, as discussed in section III.B.2 of this document, DOE proposed to adopt the use of the calorimeter test method specified in ANSI/ASHRAE Standard 16-2016 for determining the cooling mode performance in appendix F. ANSI/ASHRAE Standard 16-2016 additionally permits an air-enthalpy test method (also referred to as a psychrometric test method), in which a technician places instruments in or near the evaporator air stream to measure the rate of cooled air added to the conditioned space. DOE conducted testing to investigate any differences in test results between air-enthalpy and calorimeter approaches and found a wide range of discrepancies between the two, for both cooling capacity and efficiency. DOE expected that obtaining more accurate results would require specialized test equipment that is limited in availability and costly to design, develop, and produce and, hence, DOE did not propose to include an air-enthalpy test approach for determining cooling mode performance of room ACs. 85 FR 35700, 35715 (Jun. 11, 2020). The California IOUs agreed with DOE's conclusion to exclude the air-enthalpy test procedure in ANSI/ASHRAE Standard 16-2016. The California IOUs noted that DOE's testing, shown in the June 2020 NOPR, demonstrated that this method was unrepresentative and inconsistent, and remedying these deficiencies would be unduly burdensome. (California IOUs, No. 14 at pp. 5-6) Based on DOE's investigative testing data, DOE maintains its proposal to not allow the use of the air-enthalpy method for determining room AC cooling mode performance. 34 34 Although DOE incorporates by reference ANSI/ASHRAE Standard 16-2016, which includes an optional air-enthalpy method, only those sections in ANSI/ASHRAE Standard 16-2016 that apply to the calorimeter method are referenced in Appendix F. c. Side Curtain Heat Leakage and Infiltration Air i. Non-Louvered (Through-The-Wall) Room Air Conditioners In the June 2020 NOPR, DOE proposed to specify in appendix F that non-louvered room ACs, which are designed for through-the-wall installation, must be installed using a compatible wall sleeve (per manufacturer instructions), with the provided or manufacturer-required rear grille, and with the included trim frame and other manufacturer-provided installation materials. 85 FR 35700, 35716 (Jun. 11, 2020). The California IOUs supported DOE's language on the use of manufacturer-provided wall sleeves. However, the California IOUs expressed concern that it may not be apparent to laboratories that they should not use additional material beyond that supplied by the manufacturer. The California IOUs suggested adding the following sentence to the proposed appendix F to 10 CRF Part 430: “No sealing or insulation material other than that provided by the manufacturer shall be installed between the wall sleeve and the cabinet of the room air conditioner. ” (California IOUs, No. 14 at p. 6) DOE understands the concern about test laboratories using additional sealing and insulation material between the unit and the wall sleeve. As discussed in the June 2020 NOPR, DOE determined that testing non-louvered room ACs, with the provided or manufacturer-required rear grille, and with the included trim frame and other manufacturer-provided installation materials maximized repeatability and reproducibility. 85 FR 35700, 35716 (Jun. 11, 2020). To address the concern that test laboratories might provide additional sealing or insulation for a non-louvered room AC, DOE is clarifying in this [Text truncated at 120,000 characters. The full text is on the page linked above.] --- Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A2021-05415. Public record. Not legal advice.