If you are comparing quotes for a new air conditioner or heat pump, you may see a refrigerant name you have not met before: R-454B or R-32. This is not a sales choice. It follows a federal rule that phases down refrigerants with a high global warming potential (GWP).

What changed

Under the AIM Act, the U.S. Environmental Protection Agency (EPA) set limits on the refrigerants used in new equipment. For residential and light commercial air conditioners and heat pumps, new systems must use a refrigerant with a GWP below 700. The limit applies to systems manufactured from January 1, 2025, and split systems built from components made before that date could still be installed until January 1, 2026.

R-410A, the refrigerant in most systems installed over the last fifteen years, has a GWP of about 2,088, so new equipment is moving away from it. The two most common replacements are R-454B (GWP about 466) and R-32 (GWP about 675).

What it means for your quote

  • The quote should name the refrigerant. It belongs in an exact equipment description, next to the model numbers.
  • New split systems in 2026 should use a lower-GWP refrigerant such as R-454B or R-32. If a quote for a new system lists R-410A, ask the contractor to explain why.
  • These refrigerants are classed A2L, meaning lower toxicity and lower flammability. Equipment and installation follow updated safety standards, which is one more reason a licensed installer and a permit matter.
  • Your old refrigerant lines may or may not be reused. Ask whether the line set will be replaced or flushed, and why.

Repairing, not replacing?

The rule covers new equipment. Existing R-410A systems can still be serviced and repaired, so a repair quote that mentions R-410A is not a warning sign on its own.

Questions to ask

  1. Which refrigerant does the quoted system use?
  2. Is the equipment new stock designed for that refrigerant?
  3. Will the refrigerant line set be replaced or flushed?
  4. Who pulls the permit, and will the work be inspected?

Source: U.S. EPA, Technology Transitions under the AIM Act.

Have a quote in hand? Check it for free: the checker shows whether the equipment, line set and permit are written down.