PURPOSE: To reduce thermal load induced by a window pane by using an exhaust air system in a building.
CONSTITUTION: An exhaust air passage runs past a heat source side of a heat exchanger 11 into a doble window 1. The exhaust air is discharged by the internal part of the double window 1. Both the inside and outside of a room is cut off with the exhaust air like a curtain. Therefore, this construction eliminates heat interruption indoors from the plane of a window pane. It is possible to prevent dew condensation or cold draft and eliminate thermal effect on the plane of the window pane and enhance the air conditioning environment near a perimeter.