Heat exchange unit

A heat exchange unit comprising:

• a coolant heat exchanger disposed on a vehicle front side in an engine room in which an engine is accommodated, the engine room being capable of taking in traveling air from the vehicle front side, the coolant heat exchanger being configured to exchange heat between an engine coolant flowing through the engine and air;
• a shutter device disposed on a vehicle front side with respect to the coolant heat exchanger, the shutter device being configured to be capable of opening and closing a passage for the traveling air that is directed toward the coolant heat exchanger;
• a blower disposed on a vehicle rear side with respect to the shutter device in the engine room, the blower being configured to be switchable between a first blowing state in which air flows from the vehicle front side to the vehicle rear side with respect to the coolant heat exchanger and a second blowing state in which air flows from the vehicle rear side to the vehicle front side with respect to the coolant heat exchanger;
• an exterior heat exchanger of a refrigerant cycle in which a refrigerant circulates, the exterior heat exchanger being disposed on the vehicle rear side with respect to the shutter device in the engine room and being configured to exchange heat between air caused to flow by the blower and the refrigerant;
• and
• a controller configured to switch the blower in accordance with both a temperature of the engine coolant and a refrigerant pressure in the exterior heat exchanger, wherein the controller causes the blower to set the second blowing state while setting an open degree of the shutter device at a closing side from a maximum open degree of the shutter device, when the temperature of the engine coolant is equal to or lower than a predetermined temperature determination value and when the refrigerant pressure in the exterior heat exchanger is equal to or lower than a predetermined refrigerant pressure determination value, in a case where a switch that makes a vehicle travelable is in an on state.