THE EXPERIMENTAL RESEARCH OF MICROCHANNEL HEAT EXCHANGER ON PACKAGED AIR CONDITIONING SYSTEM

The application of microchannel heat exchanger is becoming more widely. The article experimentally researched about the application of microchannel heat exchanger(MCHX) on domestic air conditioning system. The results show that: when just change the indoor heat exchanger into the MCHX, the system had the best performance when the fin pitch of the indoor MCHX was 1.4mm. The charge of refrigerant for the new system reduced 15.9%. Meanwhile, the cooling capacity decreased by 1%, while the COP increased by 2.2% compared with the base line; when it worked in heating mode, the heating capacity increased by 3.9% higher while the COP increased by 11.2% compared with the original system. When changed all the heat exchangers into the microchannel heat exchangers, the charge of refrigerant for the system reduced 54%. Meanwhile, the cooling capacity of the new system was 0.8% higher while the COP was 5.2% higher than the original one in refrigerating mode; when changed the refrigerant into R290, the best refrigerant charge for the new system was 500g..