AIR CONDITIONING SYSTEM

PURPOSE:To make total air conditioning possible for each standard span of a building and facilitate its maintenance by installing inside each pipe shaft cover an indoor unit and a unit for exclusively treating outdoor air performing intake of outdoor air, ventilation of an indoor space, removal of dust from the outdoor air, recovery of heat from discharged indoor air, and heating (during heating of the space). CONSTITUTION:Outdoor air is drawn through a main intake duct 18; through an intake duct 20 and an outdoor air inlet 7 the outdoor air is sucked into an outdoor air-treating unit 6, where the outdoor air undergoes removal of dust and flows into an all-purpose heat exchange unit 9. On the other hand, indoor air is passed through a circulation duct 21 and sucked into the outdoor air-treating unit 6 through an indoor air inlet 14; the indoor air undergoes removal of dust by a medium-performance filter 15 and flows into the all-purpose heat exchange unit 9, where heat exchange takes place between the outdoor air and the indoor air. An indoor air-discharging fan 10b discharges the indoor air outside through an indoor air outlet 16, a discharge duct 23, and a main discharge duct 19. An outdoor air suction fan 10a causes the outdoor air to be cooled by an evaporator, flows through an outdoor air outlet 13 and an air-supply duct 22 to a mixing box 26, where the outdoor air is mixed with air blown from an outdoor unit 1, and is supplied to the air-conditioned space through outlet grilles 3 in the ceiling.