Fault diagnosis and on condition maintenance of a combined heat and power unit

Describes an expert system involved in fault diagnosis for a combined heat and power unit. The traditional expert system approach need not be restricted to failure driven maintenance systems employing troubleshooting techniques. On the contrary predictive maintenance proves equally amenable to solution via an expert systems approach. Such systems by their very nature need to have the ability to employ deep reasoning when necessary. For this reason a causal or functional model of the engine is a prerequisite