HEAT PUMP SYSTEM FOR VEHICLE AND ITS CONTROL METHOD

摘要

The present invention relates to a vehicle heat pump system and a control method thereof. More specifically, the vehicle heat pump system reduces the pressure of a coolant circulating in a coolant circulation line below a certain level and controls a direction switching valve to switch the direction when the direction switching valve is required to switch the direction while operating in an air conditioning mode or a heat pump mode to block the noise caused by the pressure difference of the coolant.