For continued superior performance and high efficiency, the operational use of heat exchangers plays an important role. A good performance and high efficiency of heat exchangers goes a long way in ensuring the increased output of the system. First and foremost is complete familiarization of the operator with the heat exchanger. There are certain set of parameters associated with the heat exchanger that every manufacturer provides along with the exchanger. Operator must ensure operation of the exchanger within such parameters. Following are the few basic tips from AIC industrial Components for ensuring higher efficiency of the heat exchanger in operation:-
(a) Flow Rate. Flow rate plays an important role in the overall performance of the heat exchanger as it decides the amount of heat being transferred. The flow rate can be monitored by installing a simple pressure gauge at the suction as well as discharge side. The pressure difference or the differential pressure between the suction and discharge indicates the flow rate of the fluid. The operator should ensure that the heat exchanger is operating at the desired differential pressure mentioned by the equipment manufacturer (OEM).
(b) Temperature Difference. This is the direct parameter that indicates the performance of the heat exchanger. It is the temperature recorded both at the inlet as well as the outlet side of the fluid getting cold and the fluid used for cooling. The outlet temperature of the fluid used for cooling should be more than the inlet temperature, whereas, the outlet temperature of the fluid that is being cooled should be less than the inlet temperature. Now the difference in outlet-inlet temperature gives an indication of the performance of heat exchanger. The operator should ensure that the parameters are within the prescribed limits.
(c) Thermostat. The initial starting of any system from cold condition does not require heat exchanger; therefore a thermostat operating valve should be installed at the inlet of the fluid being cooled. The valve will bypass the fluid till certain temperature and will open only when the temperature of the fluid has increased sufficiently where it requires to be cooled.
(d) Compatibility of Material. Though heat exchanges do not allow cross contamination of air or fluid, but they themselves interact with them owing to direct contact. If the material of the heat exchanger is not equipped to handle the material then it will corrode, leak or get damaged. Let us take a simple example- there are specific heat exchangers that come specifically built for handling Salt water pool applications or marine applications. If a usual heat exchanger is used extensively in such an environment the salts and minerals in the water would corrode and damage the heat exchanger.
The above mentioned aspects are very simple but important in ensuring the high efficiency of the heat exchanger. As mentioned earlier, the operator involved should be professional enough to know the prescribed limits of the heat exchanger and should operate only at those limits.