What homeowners should know about AC refrigerant

Refrigerant moves heat

Inside the evaporator, refrigerant absorbs heat from indoor air. The compressor raises its pressure; the outdoor coil releases heat; an expansion device lowers pressure before the cycle repeats. The refrigerant changes pressure and state but should remain inside the closed circuit.

Low charge can reduce capacity and contribute to coil icing or compressor damage, but those symptoms are not unique to charge. DOE advises that a trained technician repair a leak and recharge the system when refrigerant is low (DOE). Adding refrigerant without addressing the cause is not a complete repair.

The names identify different chemicals and equipment designs

R-22 is an older hydrochlorofluorocarbon refrigerant. New production and import have ended in the United States, while reclaimed material and service practices govern remaining systems.
R-410A is a high-global-warming-potential HFC blend widely used in equipment from the prior generation.
R-32 and R-454B are examples of lower-GWP alternatives used in newer residential equipment. They have an A2L safety classification—lower flammability than higher classes, but not interchangeable with older-system refrigerants.

Never substitute refrigerants based on a name or sales claim. Equipment, metering devices, oils, pressure ratings, sensors, controls, recovery tools, transport, and code requirements are system-specific.

What changed for new equipment

EPA’s HFC phasedown and technology-transition rules restrict certain new high-GWP products and support lower-GWP alternatives. EPA’s current homeowner FAQ explains that manufacture and import of R-410A residential and light-commercial products were prohibited beginning January 1, 2025, subject to the governing rules and transition provisions (EPA). EPA maintains a current residential AC transition fact sheet.

These rules are volatile. Verify the EPA source and applicable local code at the time of a purchase or repair.

Does an existing system need replacement?

Not automatically. Consider leak location and repairability, component and refrigerant availability, total repair cost, efficiency, reliability history, remaining condition, and the quality of a replacement design. EPA similarly lists component availability, energy efficiency, and total maintenance cost as decision factors (EPA).

Ask a contractor to state the exact refrigerant, diagnosis, leak-testing method, repair scope, recovered and added quantities, warranty, and replacement alternatives in writing.

Sources

EPA — Transitioning to low-GWP alternatives in residential and commercial AC, accessed 8/12/2026
EPA — Frequent questions on the HFC phasedown, accessed 8/12/2026
DOE — Energy Saver 101 home cooling, accessed 8/12/2026