Patent ID: 7657347

Claim:
A method of monitoring a heat exchanger, the method comprising: pre-characterizing the heat exchanger to generate pre-characterized correlation data for the heat exchanger, the pre-characterized correlation data comprising data correlating effectiveness of the heat exchanger to flow rates of a first fluid through the heat exchanger and flow rates of a second fluid through the heat exchanger, wherein when operational, heat is transferred across the heat exchanger between the first fluid and the second fluid; sensing, when operational, inlet and outlet temperatures of the first fluid passing through the heat exchanger, and inlet and outlet temperatures of the second fluid passing through the heat exchanger; automatically determining at least one of flow rate of the first fluid through the heat exchanger or flow rate of the second fluid through the heat exchanger, the automatically determining employing the pre-characterized correlation data and the sensed inlet and outlet temperatures of the first fluid and the sensed inlet and outlet temperatures of the second fluid; and outputting the determined flow rate of the first fluid or the flow rate of the second fluid through the heat exchanger.