Experimental investigation of L41b as replacement for R410A in a residential air-source heat pump water heater

The current paper presents an energy performance evaluation of low-GWP refrigerant, L-41b, as a replacement for R410A. Tests were carried out in a modified air-source heat pump water heater system, which combined varying values of the climate chamber temperature as well as the condenser outlet water temperature, together with being without/with the adoption of an internal heat exchanger (IHX). The analysis of the compressor power consumption, coupled with the heating capacity, coefficient of performance (COP) and discharge temperature, has been carried out. As the results suggest, the average COPs reductions using L-41b as fluid, are of 1.4-9.1% and 2.3-10.1% in comparison with R410A, when the climate chamber temperature or condenser outlet water temperature is fixed, respectively. The COP difference between L-41b and R410A declines with the increase in the climate chamber temperature or condenser outlet water temperature, in particular, on the activation of the IHX. Adopting an IHX has the potential of lowering the differences of performance, besides approaching the L-41b performance to that attained with the use of R410A in the existing air-source heat pump. (C) 2019 Elsevier B.V. All rights reserved.