Abstract
This paper proposes a method of fault detection for building air conditioning systems using relationships between measured data. In order to represent relationships, correlation analysis is applied to measured data. In air conditioning systems, variable machines are controlled to keep temperature of a room at a pre-set value. There are correlations among some pairs of measured data. If there are fault parts in the system, its correlations will be different from that in normal states. The fault detection can be realized by identifying the difference of correlations. At first, the parts which are controlled similarly in the system are picked up from the structure of a target system. By comparing correlation coefficient at each part, different parts can be nominated as fault.
This method was applied to a Variable Air Volume system, which is one of typical air conditioning systems. From this result, it was confirmed that most fault parts can be detected correctly.
