Hydrofluorocarbon (HFC)-134a replaced chlorofluorocarbon (CFC)-12. Now, 134a is on its way out, too.
The July 2, 2015, ruling from the U.S. Environmental Protection Agency (EPA) set forth the time frames for the phasedown of certain HFC refrigerants in specific applications. Since then, there has been no if, ands, or buts about it: The HVACR industry will be fading away from heavy use of HFC refrigerants that have unacceptable global-warming potential (GWP) values. Table 1 lists some refrigerants and their GWP values for comparison purposes.