Heat exchangers are used in a number of applications in various industries. The present study focus on calculation of shell and tube heat exchanger design with minimum pressure drop. Calculation of heat exchanger design has been done by considering with two case of different coolant are used 98ºC of water is enter to the exchanger and its outlet at 60ºC.c Water is used in case one and another case R134a is used for coolant. This study also including different coolant temperature use and MATLAB software is used to analyze for distribution of pressure drop. When a heat exchanger is placed into a thermal transfer system a temperature drop is required to transfer heat. The magnitude of this temperature drop can be decrease by utilizing a larger heat exchanger but this will be large pressure drop, increase the cost of the heat exchanger. Economic considerations are important in engineering design, and in a complete engineering equipment, not only the thermal performance characteristics but also the minimum pressure drop are requirement.