Appendix C - Appendix C to Subpart F of Part 431—Uniform Test Method for Measuring the Energy Consumption of Water-Source Heat Pumps
Manufacturers must use the results of testing under this appendix to determine compliance with the relevant standard at § 431.97 as that standard appeared in the January 1, 2023 edition of 10 CFR parts 200-499. Specifically, representations must be based on testing according to either this appendix or 10 CFR 431.96 as it appeared in the 10 CFR parts 200-499 edition revised as of January 1, 2023.
Starting on November 29, 2024, voluntary representations with respect to energy use or efficiency of water-source heat pumps with cooling capacity greater than or equal to 135,000 Btu/h and less than 760,000 Btu/h must be based on testing according to this appendix. Manufacturers may also use this appendix to make voluntary representations with respect to energy use or efficiency prior to November 29, 2024.
Starting on November 29, 2024, voluntary representations with respect to the integrated energy efficiency ratio (IEER) and applied coefficient of performance (ACOP) of water-source heat pumps must be based on testing according to appendix C1 of this subpart. Manufacturers may also use appendix C1 to make voluntary representations with respect to IEER and ACOP prior to November 29, 2024.
Starting on the compliance date for any amended energy conservation standards for water-source heat pumps based on IEER and ACOP, any representations, including compliance certifications, made with respect to the energy use or energy efficiency of water-source heat pumps must be based on testing according to appendix C1 of this subpart.
Manufacturers may also certify compliance with any amended energy conservation standards for water-source heat pumps based on IEER and ACOP prior to the applicable compliance date for those standards, and those compliance certifications must be based on testing according to appendix C1 of this subpart.
1. Incorporation by ReferenceDOE incorporated by reference in § 431.95, the entire standard for ISO 13256-1:1998. To the extent there is a conflict between the terms or provisions of a referenced industry standard and this appendix, the appendix provisions control.
2. GeneralDetermine the energy efficiency ratio (EER) and coefficient of performance (COP) in accordance with ISO 13256-1:1998.
Section 3 of this appendix provides additional instructions for determining EER and COP.
3. Additional Provisions for Equipment Set-UpThe only additional specifications that may be used in setting up the basic model for testing are those set forth in the installation and operation manual shipped with the unit. Each unit should be set up for test in accordance with the manufacturer installation and operation manuals. Sections 3.1 through 3.2 of this appendix provide specifications for addressing key information typically found in the installation and operation manuals.
3.1. If a manufacturer specifies a range of superheat, sub-cooling, and/or refrigerant pressure in its installation and operation manual for a given basic model, any value(s) within that range may be used to determine refrigerant charge or mass of refrigerant, unless the manufacturer clearly specifies a rating value in its installation and operation manual, in which case the specified rating value must be used.
3.2. The airflow rate used for testing must be that set forth in the installation and operation manuals being shipped to the commercial customer with the basic model and clearly identified as that used to generate the DOE performance ratings. If a rated airflow value for testing is not clearly identified, a value of 400 standard cubic feet per minute (scfm) per ton must be used.