Experimental investigation of cooling performance a heat pump for near azeotropic refrigerant R404A

Abstract

In this study, in order to investigate the effect of outdoor air temperatures on the performance of an air source heat pump, operated in cooling mode, using R404A refrigerant, the heat pump was tested at the outdoor air temperatures ranging from 25 °C to 30 °C and a computer code was also developed by using Engineering Equation Solver (EES). Experimental measurements have been carried out at the outdoor air temperatures ranging from 25 °C to 29 °C and they are repeated three times for better accuracy. The temperatures, the pressures, and the electric energy consumed by the compressor and the fans are measured by means of the K type thermocouple, bourdon type manometer and energy analyzer, respectively. Furthermore, an electric heater was installed in the room where the indoor unit was located and a humidifier is activated to provide the humidity conditions required for the room. The compressor pressure ratio, the power driven by the compressor, the heat rejection capacity of the outdoor unit, the cooling capacity of the indoor unit, the coefficient of performance of the heat pump (COP) were investigated according to different outdoor air temperatures. It was observed that as the outdoor air temperature increased, the indoor unit capacity and COP of the heat pump system decreased while the energy consumed by the compressor increased