It is urgent to seek more suitable refrigerants as the traditional R22 used widely in air conditioners nowadays is under phase out for its environmental problems and hydrofluorocarbons (HFCs) would aggravate global warming effects

while hydrocarbons (HCs) have drawn public attention. In this paper

R290 and R1270 were adopted as refrigerants in a R22 original split room air conditioner to carry out performance experiments using air-enthalpy test method. The results indicate that under normal condition

adopting R290 as a drop-in substitute to R22 would offer 5.0% lower cooling capacity and 10.3% higher energy efficiency ratio (EER)

and the use of the 20% larger displacement compressor could help increase cooling capacity by 8.9%

but reduce EER by 8.3%

however

the performance is better than that of the original R22 system. And the performance of the R1270 system is better than that of the R290 system under normal condition. The results also show that

with respect to the original R22 system

HC systems have higher increase rate and greater increment in both cooling capacity and EER with the decrease of outdoor temperature and they have better performance when outdoor temperature is relatively low. The results demonstrate that HCs are promising substitutes to R22 and deserve wide application prospects in air conditioners.