PURPOSE: To prevent excessive cooling or heating of a room by a method wherein an indoor set temperature is increased only in a predetermined temperature range during a cooling or drying operation, while the set temperature is decreased only in a predetermined temperature range during a heating operation with a save operation switch in the case that an indoor load is decreased.

CONSTITUTION: An operation switch or a remote control switch of a main body is provided with a save operation switch 4 for adjusting an operating condition set in response to a variation of load in a room. When no person is present (a load is decreased) in the room, the save operation switch 4 is operated to raise an indoor set temperature only in a predetermined temperature range during a cooling or a drying operation, while it is decreased only in a predetermined temperature range during a heating operation and the operation is controlled at the set temperature. With such an arrangement, it is possible to prevent an excessive cooling or heating of an indoor area.