A mathematical model has been developed to determine the best geometry of a compact heat exchanger in this research study. Accordingly, an objective function was introduced to define the optimized structure of the exchanger. Two main targets were pursued in this regard. First was the rate of existing discrepancy between the possible heat transfer rate in the exchanger and the maximum rate. Second was possible heat transfer consideration between exchanging gasses and incoming air of the furnace. A sample shell and tube heat exchanger of existing tube in a processing industry has been studied and the calculations have been performed to solve the relevant equations. In addition, a comprehensive code to design an optimized compact heat exchanger for heat recovery of the furnaces has been presented. Then, data gathering and model synchronization caused to a preliminary evaluation of model quality. Thus, for increasing accuracy level of mentioned research, along with measurements’ correction program, model modification has been done and new results were calculated. Optimization model analysis showed that by using this approach, not only significant heat conservation can be achieved, but also suggested procedure might be completely economical.