Abstract: Environmental protection alternative refrigerant has been widely promoted, at the same time, the operating environment of the air conditioner is getting worse under some special working conditions ,the demand of air conditioner which can operate efficiently under high temperature condition is increasing day by day. Three alternative refrigerants R410A, R32 and R290 are compared in high temperature physical properties, and in the same configuration of split room air conditioner refrigeration system, R410A, R32 and R290 are respectively charged to test the high temperature refrigeration capacity above 60℃ in the air-enthalpy test room. The results show that R290 is superior to R32 and R410A in capacity and energy efficiency at high temperature, the exhaust temperature is low and the system is reliable. It has a good application prospect in the middle and high temperature area.

Key words: Environmental protection refrigerant, Extreme high temperature condition, Room air conditioner