Distributed air conditioning system

Abstract

In a distributed air conditioning system capable of controlling cooling or heating by means of a substitute temperature detector when the room temperature detector of a room to be air conditioned is abnormal, room temperatures detected by the temperature detector D2 of an indoor unit 20, the temperature detector D1 of an operation unit 30 and the temperature detector D3 of a monitoring meter 86 for monitoring the environment of the room 85 to be air conditioned are monitored by a central monitoring and control board 50 and the order of selecting the temperature detectors used for the control of cooling or heating is determined. When a temperature detector selected according to the selection order is abnormal, an alarm for the abnormality is displayed by the central monitoring and control board 50 and a temperature detector which is the next in the selection order is selected to control cooling or heating of the indoor unit. By comparing temperature values detected by the temperature detectors, a temperature detector detecting a temperature value whose differences from other temperature values are equal to or more than a predetermined value is judged to be abnormal. Even when the temperature detector D2 of the indoor unit 20 becomes abnormal, it is possible to control cooling or heating without stopping the operation of the system due to an erroneous cooling or heating operation.