The present invention is directed to a system and method for monitoring the performance of a heat exchanger. In accordance with the system and method, baseline values of a performance factor (E) for baseline sets of heat exchanger operating values are calculated and stored. A current value of E is calculated for a current set of the operating values and is compared to a retrieved baseline value of E for a baseline set of the operating values that at least substantially matches the current set of the operating values. E provides a measure of the performance of the heat exchanger and is calculated using differential temperatures across the heat exchanger and without using any information concerning the physical construction of the heat exchanger.