Heat exchangers are a device that is used to transfer heat from one medium to another. These media can be a gas, liquid, or a combination of both. This paper contains the design and fabrication of shell and tube heat exchanger manually and then the analysis of the effects on heat exchanger by varying conditions such as in this case is number of baffle plates. Designing of heat exchanger is done by using kern’s method. In this experiment heat gain of cold water is analysed i.e., change in temperature of cold water with the change in temperature of hot water passed through. Two different setup of heat exchanger was made.In first setup 7 baffle plates were used and in second setup 9 baffle plates were used and in both temperature of cold water passed through was kept same and also all the inlet conditions were also kept similar as in the first setup. Readings were taken such as change in temperature of cold water by change in number of baffle plates. All the observations are discussed in detail inside this paper.