| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a composite heat source heat pump device that does not spoil a feeling of heating as much as possible by shortening a defrosting operation time.SOLUTION: A composite heat source heat pump device includes: a heating circulation circuit 30 having a heating circulation pump 32 for circulating a circulating liquid L to a heat radiation terminal 36; a first heat pump circuit 40 which heats the circulating liquid L through a first heating heat exchanger 41 arranged in the heating circulation circuit 30 by utilizing earth heat; a second heat pump circuit 50 which heats the circulating liquid L through a second heating heat exchanger 51 arranged in the heating circulation circuit 30 by utilizing air heat; and a control device 6. Further included is defrosting operation execution means 63, which executes a defrosting operation to melt frost produced on an air heat source heat exchanger with a refrigerant discharged from a second compressor by changing a selector valve 58 reversely to a flow direction in a heating operation, and which also drives a heating circulation pump 32 at a defrosting rotating speed in the defrosting operation. When the defrosting operation is performed, a second expansion valve 54 is made fully open and the defrosting rotating speed of the heating circulation pump 32 is made lower than the rotating speed in the heating operation.</p> |
