PURPOSE: To attain a high temperature and a high efficiency and to reduce a required amount of refrigerant in a heat pump type hot water feeding machine in which hot water is made by a heat pump.
CONSTITUTION: There is provided the first refrigerant circuit in which the first compressor 1, the first refrigerant-to-water heat exchanger 2, the first pressure reducing device 3, and an evaporator 4 are connected in sequence. There are provided the second compressor 5 connected to the first refrigerant-to-water heat exchanger 2, the second refrigerant-to-water heat exchanger 6, and the second pressure reducing devices in which one of them is connected to the first refrigerant-to-water heat exchanger 2 and the other is connected to the second refrigerant-to-water heat exchanger 6, respectively. Water is heated by the first refrigerant-to-water heat exchanger under utilization of a refrigerant condensing heat of the first compressor and a pressure reduced refrigerant condensing heat reduced by the second pressure reducing device and further heated by the second refrigerant-to-water heat exchanger. An operating efficiency can be improved, a compression ratio of the second compressor can be reduced and water can be heated up to a higher temperature. An over-cooling of refrigerant at the outlet of the second refrigerant-to-water heat exchanger is reduced and an amount of refrigerant is reduced.
| JP5121908 | Cooling water heater |
| JP2578781 | [Title of Invention] Water heater |
KAJITANI TOSHIMOTO
YAMAMOTO TERUO
