摘要 |
An on-off valve (70) is provided in an oil feed path (43). When liquid refrigerant enters the oil feed pipe (43) from the oil separator (22), the temperature of the liquid refrigerant whose pressure has been reduced in the on-off valve (70) dramatically decreases. When the amount of such a decrease in temperature detected by a temperature sensor (73) exceeds a specified amount, it is determined that the liquid refrigerant enters the oil feed pipe (43), and the on-off valve (70) is closed. |