When a target blown air temperature TAO is in a predetermined intermediate temperature zone, a blower is automatically stopped (S80), an outside air mode is selected when the blower 8 is automatically stopped. When an outside air temperature Tam is a first predetermined temperature (15.degree. C.) or lower, an opening degree of an air mix door is corrected to a high temperature side in comparison with the time of the operation of the blower (S120), and when the outside air temperature Tam is a second predetermined temperature (25.degree. C.) or higher, the opening degree of the air mix door is corrected to the low temperature side in comparison with the time of the operation of the blower (S130).