R-22: The predominant refrigerant installed in residential and commercial air conditioning and some very large centrifugal chillers for air conditioning and industrial process cooling. It has also been installed more in refrigeration since the phaseout of CFCs, both as a pure refrigerant and in blends. R-22 can no longer be used in new equipment, but available product can be used to service existing systems.
An EPA certification card is required to purchase CFC and HCFC refrigerants.