A family of alternatives has been developed for replacing HCFC-22 which is now used in a wide variety of applications. HFC-134a, a ternary zeotropic mixture composed of HFC-32/HFC-125/HFC-134a, and a near azeotropic mixture composed of HFC-32/HFC-125 are nonflammable, chlorine-free alternatives for replacing HCFC-22. Compares experimental performance tests with the ternary and binary mixtures in a split system residential heat pump. Equipment modifications for improving heating capacity and energy efficiency is discussed. Energy efficiency values 3% to 6% higher than HCFC-22 are predicted for the ternary and binary mixtures based on experimental data and computer modelling.

KEYWORDS: year 1995, replacing, refrigerants, unit air conditioners, heat pumps, R22, R134a, mixtures, R407C, R410B, R32, R125, energy, efficiency, thermal capacity, comparing, experiment, calculating