PURPOSE: To make a thin device by a method wherein a lateral flow fan is arranged near a heat exchanger and further installed without being overlapped on the heat exchanger in a deep direction, a fan casing is arranged at the heat exchanger, a side opposing against the fan casing is provided with a nose and then the lateral flow fan is set in a rotating direction from a rear side to a front side.

CONSTITUTION: Since a heat exchanger 13 and a lateral flow fan 14 are not overlapped in their deep direction, they may be constructed in a thin form by about 2/3 of a deep size of a conventional type indoor device in which the heat exchanger 13 and the lateral flow fan 14 are overlapped in their deep direction. In addition, since a fan casing 18 is arranged at the heat exchanger 18, a nose 19 is arranged at the side opposing against the fan casing 18 and the lateral flow fan 14 is in an opposite direction to that of the conventional type and in a rotating direction from a rear side of the heat exchanger 13 toward a front side, the air is guided to an arcular part 18a of the fan casing 18, directed toward the air blowing port 16, no disturbed flow occurs in the fan casing 18, and an amount of air can be assured and at the same time an air blowing noise can be reduced.