AIR-CONDITIONER

PURPOSE:To perform ventilation and humidifying only for rooms, requiring air-conditioning and to save energy by providing air flow adjusting devices which are to adjust the air flow and installed in ducts corresponding to the rooms to be air-conditioned, and a controller which controls the air flow rate of an outside-air suction fan of an exclusive outside-air treatment equipment. CONSTITUTION:When some of switches 15 of air flow adjusting devices are off during cooling or heating operation or at the start-up of operation, that is, when occupants are not in some of rooms 13, a controller 16 for indoor unit 2 calculates a formula as follows; (the total capacity of the air flow adjusting devices) / (the total capacity of the air flow adjusting devices in operation) X (the rated air flow of the indoor apparatus). The calculated result is transmitted to an inverter 18 for an indoor air fan 2d and to a controller 17 as well to control an inverter 19 for fans 6a and 6b according to the arithmetic operation of the controller 17. Thereby, the air flow rates of the fans 2d, 6a and 6b are controlled according to the calculated result of the above formula. Therefore, the outside-air intake amount and humidifying amount can be controlled according to the occupation status of the rooms 13, resulting in energy saving and low level noise operation.