| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a heat pump water heater capable of defrosting an evaporator without increasing electric power consumption and complicating the device and a method for defrosting the heat pump water heater. <P>SOLUTION: The heat pump water heater includes: the evaporator for evaporating a refrigerant through heat exchange with outside air; a compressor for compressing the evaporated refrigerant; a radiator provided below the evaporator and generating hot water by heat exchange with the compressed refrigerant; an expansion means for decompressing the refrigerant after heat exchange with water; a heat storage tank for storing hot water; a first refrigerant circulating circuit which interconnects the evaporator, the compressor, the radiator and the expansion means and in which a refrigerant is circulated during normal operation; a second refrigerant circulating circuit which interconnects the evaporator, a first bypass bypassing the compressor, the radiator and a second bypass bypassing the expansion means and in which a refrigerant is circulated during a defrosting operation; and a switching means for switching the first refrigerant circulating circuit and the second refrigerant circulating circuit. <P>COPYRIGHT: (C)2010,JPO&INPIT |
