| 摘要 |
PROBLEM TO BE SOLVED: To improve efficiency during cooling operation.SOLUTION: In a refrigerant circulation circuit, a first three-way valve 26 is installed between a four-way valve 10 and a water-refrigerant heat exchanger 15, and a second three-way valve 27 is installed between the water-refrigerant heat exchanger and an outdoor heat exchanger 11. A first expansion valve 12a is arranged between the second three-way valve and the outdoor heat exchanger, and the outdoor heat exchanger is formed by a fin tube type heat exchanger. A refrigerant flow route is divided vertically, and a second expansion valve 12b is installed between an upper refrigerant flow route 29 and a lower refrigerant flow route 30. During heating operation, the first expansion valve is fully opened and the second expansion valve is narrowed, so that the upper refrigerant flow route has a low temperature and the lower refrigerant flow route has a high temperature to heat the upper refrigerant flow route. During cooling operation, the second expansion valve is fully opened and the first expansion valve is narrowed, so that both of the upper refrigerant flow route and the lower refrigerant flow route have high temperatures. |
