AIR CONDITIONING METHOD

PURPOSE:To heat or cool a building so as to allow the air in the ceiling space to move to the room space when the room is being used by preventing the air in the ceiling space from leaking to the room space when the room is not being used. CONSTITUTION:When the room is not being used, the air cooled by an air conditioner 1 passes through a duct 2 to be discharged from an outlet 2a into the space A in the ceiling, and, after heating or cooling the casing 8 enveloping the ceiling space, id drawn via an inlet 3c of a duct 3a to be heated or cooled by the air conditioner 1 for circulation. When the room is being used, a buffle plate 7 is lowered to release an air outlet 6. Then, the air blown out of the duct 2 is heated or cooled by the casing which has been heated or cooled when the room was not being used for heating or cooling of the room. In this instance, a switch valve of the air conditioner 1 may be switched so that the drawing of air may be conducted not from the air drawing duct 3a on the ceiling side but from the air drawing duct 3b.