PURPOSE: To prevent feeling of air stream, ununiform room temperature distribution and noise during heating a room by a method wherein a control unit, which stops a fan during room heating operation and drives the fan during room cooling operation, is provided in the titled device.

CONSTITUTION: The control unit 6 switches the operation of the fan 3, depending on whether it is room cooling operation or room heating operation. During room cooling operation, refrigerant is evaporated in a heat exchanger unit 7 and the control unit 6 drives the fan 3 to effect heat exchange in indoor air by forced convection and cool the room. On the other hand, during room heating operation, the refrigerant is condensed in the heat exchanger 7 and the control unit 6 stops the fan 3 to effect heat exchange in the indoor air by natural convection and heat the room. The fan 3 is stopped during room heating operation. Accordingly, noise is not generated, no air stream is felt by body and room temperature distribution is uniform, thereby making the room heating comfortable.