Heat cycle system for vehicle, has control device executing three operating modes controlling degree of opening of valve, so that exchanger evacuates coolant heat towards exterior air or coolant evacuates heat towards air

摘要

The system has a control device executing three operating modes. One of the modes controls a degree of opening of a pressure reduction valve (113), so that temperature of a coolant discharged from a compressor (111) is equal to the temperature of hot water in a water-coolant heat exchanger (112) and the exchanger evacuates the coolant heat towards exterior air. Another mode controls the degree of opening to reduce the coolant pressure, so that the coolant temperature is less than that of the hot water and the coolant absorbs heat from the water and evacuates the heat towards the air. The third operating mode of the control device is used for controlling a degree of opening of the pressure reduction valve to a preset level for leading the heat exchanger to evacuate heat from the coolant towards hot water. Independent claims are also included for the following: (1) a device for controlling a heat cycle system (2) a method for controlling a heat cycle system.