Abstract: According to the disclosure the amount of wind for an air cleaner is controlled regardless of the initial value of the air pollution level sensed by a sensor in an air cleaner. This allows the air cleaner to efficiently perform the air cleaning regardless of the area in which the air cleaner is installed. The method for cleaning the air requires that an initial value of the air pollution is sensed. Thereafter, an air pollution grade from a plurality of air pollution grades having a plurality of blow control sections set according to each of the air pollution grades. A present value of the air pollution is then sensed. An increment of air pollution is determined from the initial value of the air pollution and the value of the air pollution sensed at a later time. Based on this increment that has been determined, the amount of air from the air cleaner is controlled depending on that increment.

Abstract: A cooling/heating apparatus having an automatic ventilating function and its method switches the ventilating function and the cooling/heating function in response to the pollution state of room air and maintains the room air in a pleasant state. The apparatus and method rotates the cooling/heating fan and the ventilating fan to be mutually supplemented and completed by the output of a gas sensor which changes its resistance value in response to the air pollution state within a room. The ventilating fan is rotated instead of said cooling/heating fan when the room air is polluted and ventilates the polluted air within a room.