Charge Limits for Heat Pumps with Flammable Refrigerants
There has long been a focus on the climate impact of refrigerants, and now the political climate and legislation is forcing all users of traditional HCFC and HFC refrigerants to consider options with lower climate impact. Lower GWP refrigerants include CO2 (R744) and NH3 (R717), but the focus of this article is on the charge limits set by the safety standards when using flammable A2L and A3 refrigerants, including propane (R290), R32 and the unsaturated HFC (HFO) options.