Abstract: A sensor (24) is provided to sense the humidity at the inner surface of a window of a vehicle interior. When the sensed surface humidity is above a certain value, the possibility of the window being fogged arises and a humidifier (28) is de-energized. The humidifier (28) is normally operated to increase the interior humidity to within a desirable range. When the surface humidity is above a higher value, the air interior air control system is operated to reduce the interior humidity by turning on a defroster or the like in accordance with the outside air temperature.

Abstract: Disclosed is a temperature control apparatus for an air conditioner of an automobile. This temperature control apparatus comprises a push button switch for elevating the set temperature and a push button switch for lowering the set temperature.Every time the push button switch for elevating the set temperature is depressed, the set temperature can be elevated by, for example, 1.degree. C. On the other hand, every time the push button switch for lowering the set temperature is depressed, the set temperature can be lowered by, for example, 1.degree. C. Accordingly, the temperature can easily be set at an optional level by operating these switches appropriately. The so set temperature is digitally and visually displayed very clearly by a digital indicator.