Under the US EPA’s Technology Transitions rule, finalized in October 2023 under the American Innovation and Manufacturing (AIM) Act, new residential and light-commercial air conditioning and heat pump systems using refrigerants with a global warming potential above 700 can no longer be manufactured or imported as of January 1, 2025. That covers systems using R-410A, which has been the standard refrigerant for decades.
Under the current rules, systems made or imported before 2025 can still be installed until January 1, 2026. Separate dates apply to variable refrigerant flow (VRF) systems.
The new refrigerants
Replacement equipment mostly uses A2L refrigerants such as R-454B and R-32. They have a much lower global warming potential, but they are classed as mildly flammable. That brings changes to equipment design, installation practice, leak detection and the training technicians need.
What it means for projects
- Equipment selections and specifications need to reflect the new refrigerants and their requirements.
- Owners with existing R-410A systems will be maintaining them for years, alongside new A2L equipment.
- Lead times and pricing may be uneven while the supply chain shifts over.
We review refrigerant requirements during preconstruction on every mechanical scope, so equipment choices match the rules that apply when it’s installed.
Update, June 2026: EPA has since removed the January 1, 2026 installation deadline. Read the update.
