Central air conditioning equipment

Central air-conditioning equipment which performs air-conditioning for a plurality of rooms, comprising:

• an air-conditioner which includes a heat exchanger and a blower for blowing air, the heat of which is exchanged in said heat exchanger;
• a duct which distributes the air blown from said blower to said room;
• a plurality of terminal air quantity control units which are installed in order to communicate with the rooms, respectively, and which control the quantities of the air which are distributed to the rooms through said duct, each of said terminals air quantity control unit including a main body through which the air passes, an air quantity sensor which detects a flow rate of the air which passes through said main body, a damper which is disposed in said main body and which is movable between a first position where the main body is open to a maximum state, and a second position where the main body is completely closed, a drive mechanism which drives said damper, a setter which is disposed in a corresponding room and which sets the quantity of the air which is distributed to the corresponding room, and a unit controller which controls said drive mechanism in order to match the quantity of the air which actually passes to the quantity of air which is set based on the air quantity detected by said air quantity sensor and the air quantity set at said setter;
• and
• an air quantity control device, attached to said air conditioner, which controls said blower to reduce the blown air quantity when none of the dampers of the terminal air quantity control units are in the first position until at least one of said dampers reach said first position and then, controls the blower to increase the air flow in the terminal air quantity control unit in which said damper has reached the first position, when the air quantity detected by the air quantity sensor is less than the air quantity set by the setter, and which controls said blower to maintain the blown air quantity when the air quantity detected by said air quantity sensor is equal to the air quantity set by said setter.