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R-22 Replacement Status.

pdf icon R-22 Replacement Status. (645 K)
Calm, J. M.; Domanski, P. A.

ASHRAE Journal, Vol. 46, No. 8, 29-39, August 2004.


refrigerants; environmental effects; thermodynamic properties; transport properties; air conditioning; hydrocarbons; compatibility


Since its initial recognition in 1928 and commercialization in 1936, R-22 has been applied in systems ranging from the smallest window air conditioners to the largest chillers and heat pumps, including those for district cooling and heating. Individual equipment using this versatile refrigerant ranges from 2 kW to 33 MW (0.5 to 9,500 tons) in cooling capacity. R-22 use includes equipment with rotary-rolling-piston, reciprocating- piston, scroll, screw, and centrifugal compressors and, experimentally, absorption cycles. No other refrigerant has achieved such a wide range of commercial capacities or applications.