ASHRAE - American Society of Heating@ Refrigerating and Air-Conditioning Engineers@ Inc.
Scope
This paper addresses the challenge of improving the performance of heat pumps (HPs) in cold-climate conditions by applying refrigerant mixtures. The potential benefits of implementing R-32/CO2 zeotropic refrigerant mixtures in three different residential air-sourceHPsfor cold climates are studied.ThecasesconsideredareconventionalresidentialHP@ HPwith a variable mixture control system@ andHPwith a variable compressor speed.The seasonal performance of a heating system with these air-source HPs@ supplemented with an auxiliary electric heater@ is studied in the cold-climate city of Montreal@ Canada. To this aim@ a detailed screeningHPmodel previously developed is modified and used. The obtained results highlight the potentialHPperformanceimprovementof applying refrigerant mixtures.