COMPOSITE DUAL REFRIGERATION CYCLE DEVICE

摘要

Provided is a composite dual refrigeration cycle device provided with: two high-temperature side refrigeration circuits respectively having water/refrigerant heat exchangers for heat exchange of water and a refrigerant discharged from a compressor on the high-temperature side, and two low-temperature side refrigeration circuits respectively having evaporators comprising air heat exchangers having blower fans, the circuits being built into the same chassis; and with hot water lines configured to permit heat exchange from the respective high-temperature side refrigeration circuits to the respective low-temperature side refrigeration circuits by a cascade heat exchanger, for circulating cold water or hot water to the cold water-side flow channel of the water/refrigerant heat exchangers of the high-temperature side refrigeration circuits, the interior of the chassis being furnished with a control device for overall control of operation of the device. The composite dual refrigeration cycle device is characterized in that the device is configured such that the two low-temperature side refrigeration circuits are connected to the control device, and when one of the low-temperature side refrigeration circuits performs a defrosting operation of the evaporator thereof, the other low-temperature side refrigeration circuit is controlled so as to perform heat exchange with the cascade heat exchanger, while the rotation speed of the blower fan of the other low-temperature side refrigeration circuit is controlled to a rotation speed higher than the rotation speed of the blower fan during a heating operation of both of the low-temperature side refrigeration circuits together.