| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a convenient instantaneous heat pump water heater shortening a rising time and improving low temperature flooded characteristics. <P>SOLUTION: This heat pump water heater comprises a heat pump refrigerant circuit with a compressor, a water-refrigerant heat exchanger, a refrigerant regulating valve and an evaporator sequentially connected through refrigerant piping; a direct hot water supply circuit supplied with heated hot and cold water by heating a water supplied from the outside, by the water-refrigerant heat exchanger through water piping, and a compressor operation control means for controlling to stop the compressor and to close a refrigerant regulating valve when stopping the operation of the compressor, and to restart the compressor after opening the refrigerant regulating valve when reoperating the compressor. When stopping the operation, the refrigerant in the evaporator is thereby recovered onto the compressor side, and after the stop, the evaporator is closed in front and in the rear with the refrigerant regulating valve and a backflow preventing valve to prevent retention of a liquid refrigerant into the evaporator. <P>COPYRIGHT: (C)2007,JPO&INPIT |
