| 摘要 |
The heat pump system (1) has a bypass circuit (30) for forming a connection to the intake side of a compressor (21) from the portion of a main refrigerant circuit (20) that extends from the outlet of a usage-side heat exchanger (41) to a heat-source-side expansion valve (28), the main refrigerant circuit (20) being formed by connecting a variable-capacity compressor (21), a usage-side heat exchanger (41), a variable-type heat-source-side expansion valve (28), and a heat-source-side heat exchanger (26). The bypass circuit (30) has a bypass tube (31), and a bypass expansion valve (32) for depressurizing the liquid refrigerant flowing through the bypass tube (31). The bypass expansion valve (32) is a variable-type bypass expansion valve. A controller (1a) performs liquid injection control for controlling the bypass expansion valve (32) so that the discharge temperature (Td) of the compressor (21) is equal to a target discharge temperature (Tds); and determines the upper limit opening degree (OPix) of the bypass expansion valve (32) in liquid injection control by a correlation value with respect to the opening degree (one) of the heat-source-side expansion valve (28). |
