Numerical modelling and seasonal performance analysis of air-to-water heat pumps using low-GWP refrigerant R-454B as an alternative to R-410A

In this paper, a numerical model for air-to-water heat pumps is presented and validated with experimental data. The model is used with the aim to test the differences, in terms of seasonal energy performances, obtained by using the low-GWP refrigerant R-454B as alternative to R-410A. Each component of the heat pump (i.e. compressor, heat exchangers, fans, expansion valve) is modelled and its thermodynamic performance is evaluated following nested iterative cycles. Different configurations of the heat pump have been simulated. Results confirm that R-454B is a valid alternative to R-410A. An increase of the heat pump seasonal energy efficiency ratio (SEER) up to 2.5% can be obtained with the low-GWP refrigerant.