Comparison between HFCs and HFO/HFC blends in a commercial heat pump.

Currently HFO usage is increasing as HFC refrigerants are subjected to ever more stringent F-Gas placing on the market caps which reduce quantity and increase the price for the end user. The majority of heat pumps on the market are designed to utilise HFCs as the working fluid. Direct drop-in replacement HFOs are not presently available, therefore numerous gas manufacturers have synthesised blends of HFOs and HFCs to comply with F-gas regulations whilst meeting end user requirements. In many developing countries, heat pumps are common with HFC-32 as the working fluid. HFC-32 has a moderate GWP, classified as A2L and its popularity is spreading due to production caps on high-GWP fluids dictated by F-gas regulations. Comparison is made between HFC-410A, HFC-32 and two HFO/HFC blends of moderate GWP values. HFC-32 and both blends performed well in terms of CoP, without requiring modification to the heat pump, compared to the manufacturer’s recommendation of HFC-410A. Coefficient of performance (CoP) is increased by 6, 15 and 9% respectively for HPR1D, HPR2A and HFC-32.