Abstract: In a refrigerant cycle system having a hot gas heater function, a valve device includes a solenoid valve for opening and closing a communication between a compressor and a condenser, a differential pressure valve opened by a pressure difference between a discharge side of the compressor and an inlet side of the condenser when the solenoid valve is closed for directly introducing gas refrigerant from the discharge side of the compressor into an evaporator, and a check valve for preventing refrigerant discharged from the compressor from flowing into the condenser when the solenoid valve is opened. In the valve device, at least the three valves are integrated by a housing member to construct an integrated member.

Abstract: A switch valve is provided in a refrigerant circuit. The switch valve includes a first valve mechanism, a second valve mechanism, and a single valve housing incorporating the first and second valve mechanisms. The first valve mechanism is an electromagnetic valve. The first valve mechanism selectively connects and disconnects an outlet of a compressor with an inlet of a condenser in accordance with an electric current supply. The second valve mechanism is a differential pressure valve. The second valve mechanism selectively connects and disconnects the outlet of the compressor with an inlet of an evaporator in accordance with a difference between the pressure at the outlet of the compressor and the pressure at the inlet of the condenser. In this manner, the single switch valve, which includes the first and second valve mechanisms incorporated in the same valve housing, switches the refrigerant circuit between a path for a cooling operation and a path for a warming operation.

Abstract: In a refrigerant cycle system having a hot gas heater function, a valve device includes a solenoid valve for opening and closing a communication between a compressor and a condenser, a differential pressure valve opened by a pressure difference between a discharge side of the compressor and an inlet side of the condenser when the solenoid valve is closed for directly introducing gas refrigerant from the discharge side of the compressor into an evaporator, and a check valve for preventing refrigerant discharged from the compressor from flowing into the condenser when the solenoid valve is opened. In the valve device, at least the three valves are integrated by a housing member to construct an integrated member.