Abstract: A zoned HVAC system for a building is provided with three control zones: an internal zone (14), a perimeter zone (16) and a skin zone (18). The internal zone (14) provides cooling of internal heating loads from equipment and personnel as determined from internal zone (14) thermostats (43, 46, 48). Perimeter zone (16) provides cooling against interior and solar heating loads, with thermostats (51, 52, 53, 54) controlling associated sectors dampers (56, 57, 58, 59). The skin zone (18) provides both heating and cooling against thermal transmissions through the building exterior (10). Each skin zone sector (30, 31) is assigned to a plurality of perimeter zones (24, 25, 26, 27). Operation of a skin zone sector (e.g. 30) is effected by a control box (e.g. 64) receiving inputs from perimeter zone thermostats (e.g. 51, 52) with a control output functionally related to the perimeter zone sector with the lowest cooling demand.

Abstract: The invention provides an air terminal capable of serving multiple zones with either variable volume, constant temperature air or variable temperature, constant volume air, or both, without any reheating of cold air. The terminal consists of a cold air plenum and a return air plenum. The cold air plenum is served with cold air from a primary cold duct. The air is introduced into this plenum through a damper which is controlled by a regulator for maintaining a constant pressure in the cold air plenum. The return air plenum is supplied with return air by a constant pressure recirculating fan mounted in the terminal. Constant volume, variable temperature air is supplied to the zones through thermostatically controlled mixing dampers which mix air from the cold plenum with air from the return plenum. A heating unit downstream from the mixing dampers selectively raises the temperature of the air provided to a zone.

Abstract: Disclosed is an air-conditioning apparatus for use in controlling the temperature of air in and delivered to a plurality of rooms or spaces. The apparatus has a central utility means which supplies a pressurized volume of cold air. Ducting is provided to connect the cold air supply to a plurality of distribution units, at least one of which is mounted in the vicinity of each room or space. Each distribution unit has a mixing chamber which is in fluid communication with the ducting to allow cool air to flow from the ducting into the mixing chamber. Mounted within the mixing chamber is a blower which causes air to flow from the interior of the mixing chamber through an outlet into the room to be conditioned. Control means are present in the ducting adjacent the distribution unit to sense the presence of pressurized cool air and in turn actuate the unit and blower to cause a flow of air from the mixing chamber. An inlet damper is provided to control the flow of cool air from the ducting into the mixing chamber.