22 February 2002
A traditional heat pump with one-stage compression can not meet the high pressure ratio caused by the very low outdoor temperature. A new heat pump cycle is development for cold regions with two-stage compression in one scroll compressor with a supplementary circuit. Both he calculation and the experiment results show that the new heat pump can not only realize enough heating capacity with high EER but also improve the heat pump cycle by decreasing the discharge temperature even under the low evaporating temperature of –25oC. The developed heat pump system can be used for heating in cold regions.