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The Application of HFCs as Refrigerants



David Didion


The technical criteria for using hydrofluorocarbons (HFCs), as refrigerants in the vapor compression cycle, is presented. If thermodynamic performance is to be optimzed, particular attention must be paid to the fluid's critical point and molar heat capacity. A reasonable balance between volumetric capacity, which implies equipment size, and coefficient of performance is best achieved by selecting a refrigerant of appropriate vapor pressure. To achieve these balances for the many different applications, both azeotropic and zeotropic mixtures of HFCs are now in use. The characteristics and performance advantages and disadvantages of these mixtures are discussed. Additional physical considerations, i.e. toxicity and flammability, are also discussed.
Proceedings Title
International Congress of Refrigeration, 20th Proceedings
Conference Dates
September 19-24, 1999
Conference Location
Sydney, AS
Conference Title
International Congress on Refrigeration


azeotropic, flammability, HFCs, hydrofluorocarbons, refrigerants, toxicity, zeotropic


Didion, D. (1999), The Application of HFCs as Refrigerants, International Congress of Refrigeration, 20th Proceedings, Sydney, AS, [online], (Accessed April 12, 2024)
Created September 24, 1999, Updated February 17, 2017