Method, system and computer software for diagnosing a compressor. The method includes generating a feature vector of the compressor, the feature vector of the compressor including components describing states of various parts of the compressor; determining, based on fuzzy constraints, an aggregated anomaly vector corresponding to the feature vector; defining rules for a preset list of possible faults/failure modes of the compressor; calculating a corroborating measure between the aggregated anomaly vector and the rules; and identifying a fault/failure mode of the compressor based on a result of the corroborating measure.