抄録
We have a conclusion that the hybrid heat pump system is usable for melting snow from viewpoints of the performance and the economical effect, which uses dual heat sources of the geothermal and the ambient air by means of two evaporators in series arrangement. The addition of a geothermal-source evaporator next to the air-source evaporator of a heat pump tends to increase the pressure loss of the refrigerant flow in the process of evaporation. The most difficult subject for the hybrid heat pump system is to lessen the pressure loss without dropping the performance of the heat transfer of the geothermal-source evaporator. In this development, the above subject was solved by means of using small-sized flooded-type instead of dry-type for the second evaporator, and the performance of the heat pump was improved sharply.