An ECU executes a maximum cooling mode. In this mode, the ECU drives each corresponding component of the heat medium circuit such that one of the first and second heat exchangers performs a heat-releasing function, the other one of the first and second heat exchangers performs a heat-absorbing function, and an external heat exchanger performs the heat-releasing function. The ECU drives an air path switching mechanism such that air, which has passed through the one of the first and second heat exchangers without passing through the other one of the first and second heat exchangers, is discharged from a discharge opening to outside a vehicle, and the air, which has passed through the other one of the first and second heat exchangers without passing through the one of the first and second heat exchangers, is blown from an outlet opening into a vehicle cabin.