HCFC-22, commonly called R-22, has been the standard for refrigerant used in heat pumps and air conditioners for the past 40 years. The release of R-22 from manufacturing, leaks, misuse and decommissioning have all contributed to ozone depletion that contributes to global warming. New refrigerant are now available and as of January 2020 R-22 is no longer to be produce.