To install an apparatus in a narrow installing space in a car body without taking the space area when switching the rotational direction of a cooling fan by a directional control valve, and to minimize a device cost by reducing the number of part items such as a pipe and the like by simplifying a structure.

An engine 5, a radiator 23, and the cooling fan 36 are arranged in order on one side in a driver's cabin 21 of a vehicle 20. The directional control valve 12 for switching the rotational direction of the cooling fan 36 is arranged in the close vicinity of the cooling fan 36. The directional control valve 12 is switched to a normal rotation position, and when the cooling fan 36 rotates in the normal rotation direction, the radiator 23 is cooled. The directional control valve 12 is switched to a reverse rotation position, and when the cooling fan 36 rotates in the reverse rotation direction, refuses clogged in the radiator 23 can be blown away.