The radiating section (830) of the control unit (800) is exposed to air flowing in the intake path (710) formed in the panel body (450). Due to the foregoing, it is possible to cool the control unit (800) by air (about 35° C.), the temperature of which is lower than the temperature of air (about 60° C.) which has passed through the condenser (200) and the radiator (100). Accordingly, the cooling effect (cooling capacity) can be enhanced. Therefore, the size of the radiating section (830) can be reduced, and the structure of the control unit (800) (the mounting structure of the electronic parts (810)) can be simplified. As a result, the manufacturing cost of the control unit (800) can be reduced.