The proposed listings are for comfort cooling applications of such chillers under EPA’s proposed use conditions, including but not limited to use in commercial air conditioning and industrial process air conditioning. These refrigerants may be used only in new equipment designed specifically and clearly identified for the refrigerant — none of these substitutes may be used as a conversion or “retrofit” refrigerant for existing equipment.

For residential dehumidifiers, the proposed listing is for HFO-1234yf, HFC-32, R-452B, R-454A, R-454B, and R-454C as acceptable, subject to use conditions, for use in new residential dehumidifiers end-use. For non-residential dehumidifiers, the proposed listing is for HFC-32 as acceptable, subject to use conditions, for use in new non-residential dehumidifiers end-use.

For residential and light commercial air conditioners and heat pumps, the proposed listing is for HFC-32 as acceptable, subject to use conditions, for use in new self-contained room air conditioner and heat pump end-use. EPA previously listed HFC-32 as acceptable, subject to use conditions, in new self-contained room air conditioners and heat pumps in SNAP Rule 19. Under the most recent rulemaking, EPA is proposing to update those use conditions to be consistent with use conditions applied to other refrigerants with lower flammability as finalized in SNAP Rule 23. The proposed use conditions would be required on all such equipment manufactured on or after the effective date of the final rule and would not apply to or affect equipment manufactured before the effective date of the final action and manufactured in compliance with the SNAP requirements applicable at the time of manufacture.

For very low-temperature refrigeration (VLTR), the proposed listing is for R-1150 as acceptable, subject to use conditions and narrowed use limits, for use in VLTR end-use.

Comments on the rule must be received on or before September 12, 2022 and can be made online here.