R-22 is a pure HCFC (hydrochlorofluorocarbon) refrigerant which has properties that make it a good heat transfer medium. The EPA barred this refrigerant from being used in new systems effective January 1, 2010. Production in the United States shifted to R-410A refrigerant, which is a binary blend HFC (hydrofluorocarbon) that also has good heat transfer properties. R-410A operates at approximately 50% higher pressure than R-22.