Experimental study of small wall room air conditioner for R-22 retrofitted with R290 95.5%

This study discusses the use of HC-290 with 95.5% propane content as a safe and energy-efficient alternative for retrofitting of R22. The set-up equipment consists of a compressor, condenser, evaporator and capillary tube. The system test is performed using a variation of evaporator entrance temperature as the cooling load. Temperatures were varied 20°C, 23°C, 25°C, 29°C, respectively. The small wall room air conditioner was charged by R22 according to the nameplate and R-290 with a variation of 30%, 40%, 50% and 60% of total mass according to the nameplate. R290 has a higher refrigeration effect than R22. But R22 has cooling capacity higher than R290. The highest electrical consumption was the air conditioner, which was charged by R22 and was followed by propane 95.5% with 60%, 50%, 40% and 30% charging. The average electrical consumption of the air conditioner charged by R22 was 1.5 times the air conditioner to be charged by R290. The highest COP was obtained by propane 95.5% with 60% charging and followed by R22. While propane 95% with 30%, 40%, and 50% charging had low COP.