Drop-in assessment of plug-in R404A refrigeration equipment using low-global warming potential mixtures

Abstract

Abstract This study analyses the performance of plug-in refrigeration equipment, which has the condenser on the system and delivers heat to the indoor medium, using mixtures with low-global warming potential (GWP). The theoretical drop-in replacement of R404A that is widely used in the plug-in refrigeration equipment, is investigated utilizing refrigerants with GWP<150 such as R454C, R455A, R457A and R465A. In the study, four cases of evaporation temperatures (-25°C, -15°C, -5°C and 0°C) and two cases of condenser temperatures (30°C and 40°C) were considered for freezer and chiller modes of the equipment. According to the obtained results, the power consumption of R404A is determined to be higher than other refrigerants for both studied condenser temperatures. The mass flow rate circulating in the system decreases using R404A’s alternatives. Furthermore, the highest COP is reached with R457A which has a greater COP than R404A about by 8.5%. The compressor discharge pressures of alternative refrigerants are smaller compared to R404A as well. The reduction in CO2 emission is also presented in terms of total equivalent warming impact (TEWI) computations. The conducted analysis points out that it will be possible to use directly the investigated mixtures (especially R457A and R455A are most promising ones) in plug-in refrigeration devices as alternatives to R404A without performing any constructional modification in the system.