Current international regulations set incentives to replace refrigerants with high global warming potential(GWP) values using environmentally friendly alternatives. This study presents the field measurements of anindirect commercial refrigeration system retrofitted with R449A, an alternative to R404A with a GWP valueof 1282 (67% lower than that of R404A). The system has been operated at low evaporation temperatureconditions(secondary refrigerant temperatures from -34 to -25 °C ). The results indicate that the coolingcapacity of the retrofitted system was 1.3% lower than that of the reference R404A system on average, whilethe COP values are higher when using R449A (8.1% increase on average). The compressor dischargetemperature increase is approximately 18.5 K. As a conclusion, R449A can be used as a replacement toR404A in indirect low-temperature supermarket refrigeration systems given that implications of its highercompressor discharge temperature, lower mass flow and difference in transport properties are taken intoconsideration.
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