R-410A

On December 27, 2020, the United States Congress passed the American Innovation and Manufacturing (AIM) Act, which directs US Environmental Protection Agency (EPA) to phase down production and consumption of hydrofluorocarbons (HFCs).

Carrier Corporation was the first company to introduce an R-410A-based residential air conditioning unit into the market in 1996 and holds the trademark "Puron".

[7] In accordance with terms and agreement reached in the Montreal Protocol (The Montreal Protocol on Substances That Deplete the Ozone Layer), the United States Environmental Protection Agency mandated that production or import of R-22 along with other hydrochlorofluorocarbons (HCFCs) be phased out in the United States.

[9] Further, R-410A had largely replaced R-22 as the preferred refrigerant for use in residential and commercial air conditioners in Japan and Europe, as well as the United States.

Alternative refrigerants are available, including hydrofluoroolefins, R-454B (a zeotropic blend of R-32 and R-1234yf), hydrocarbons (such as propane R-290 and isobutane R-600A), and even carbon dioxide (R-744, GWP = 1).

Some alternatives have mild or moderate flammability, operate in higher pressure ranges, or require specialized compressor lubricants and seals.

R-410A systems thus require service personnel to use different tools, equipment, safety standards, and techniques to manage the higher pressure.