HVAC&R PERFORMANCE DEGRADATION MONITOR AND RELATION BUILDER
A monitoring system for an HVAC&R system, the monitoring system comprising: a data acquisition processor operable to acquire observations about the HVAC&R system, the observations including fluid temperature measurements for a condenser and for an evaporator, the observations further including compressor input power parameter measurements corresponding to the fluid temperature measurements; a relation builder operable to learn a compressor input power parameter (CIPP) relation between fluid temperature measurements for an evaporator intake temperature and a condenser intake temperature and the compressor input power parameter measurements, and further operable to learn an evaporator temperature drop (ETD) relation between the fluid temperature measurements for the evaporator intake temperature and the condenser intake temperature and an evaporator temperature drop; and a temperature map containing a plurality of cells, each cell corresponding to a temperature tuple composed of a condenser intake temperature and an evaporator intake temperature, the temperature map configured to receive and store for each cell, from the relation builder, summary statistics for a measured compressor input power parameter, or a measurement derived evaporator temperature drop, or both, corresponding to the temperature tuple for said cell; wherein the processor-executable instructions further cause the at least one processor to use the CIPP relation or the ETD relation to compute a predicted value for a compressor input power parameter and/or a predicted value for a evaporator temperature drop, respectively, and based on these predicted values declare that performance degradation is present for the HVAC&R system.