The R-410A refrigerant change, for homeowners

The rule in brief

EPA's Technology Transitions rule, issued under the AIM Act, caps global warming potential at 700 for new residential and light commercial AC and heat pump systems, effective January 1, 2025. R-32 falls under that cap, per EPA's FAQ, which also classes both R-32 and R-454B as mildly flammable and limits them to equipment built for them.

EPA has already revised the rule once. The original text would have barred installing new R-410A systems after January 1, 2026, even ones built from older parts. A reconsideration rule dated May 26, 2026 dropped that cutoff for systems whose components were all made or imported before January 1, 2025, according to EPA's sector table as updated August 28, 2026. Some older EPA pages still carry the earlier date.

Owners of R-410A equipment

• EPA says the system can stay in service and keep being repaired.
• Per EPA's FAQ, a dead condensing unit, an indoor coil or a smaller component may be swapped for a comparable R-410A part, because parts used to repair existing systems fall outside the restriction.
• Any R-410A part manufactured after January 1, 2025 has to carry a label limiting it to servicing existing equipment.

Buying a replacement

Expect a new system to run on one of the newer refrigerants, with an outdoor unit and indoor coil designed to work together. Bolting a new condenser onto the old R-410A coil is a different job from installing a matched system. Ask each bidder which refrigerant the quoted unit uses and whether the coil is part of the price. Installation costs.

The technician working with refrigerant must hold EPA Section 608 certification, which EPA requires for anyone servicing equipment that could release it. Efficiency rules are on a separate track: a split AC installed in Missouri since 2023 has to meet at least 13.4 SEER2, refrigerant change or not.