The apparatus consists of fabricated SS shell, inside which SS tubes are fitted. Hot water passes to one end through the tubes and exit to another end. The cold water is admitted at the one end of shell, which passes over the hot-water tubes. The tubes are arranged in the shell so that the flow of cold and hot fluid crosses each other to make it cross flow. For hot water, a recirculation type water tank is provided, fitted with heaters and Digital temperature controller. Cold water at constant head condition is to be provided from laboratory overhead tank by the end user. Flow rates of hot and cold water are measured using Rotameters. A magnetic drive pump issued to circulate the hot water from recirculation type water tank. It has an interfacing unit designed by Engineers along with Labview software. This educational software allows/enables user to log the real time experimental data and tabulate the experimental/sample reading according to the requirement of experiment. User have a control on data logging, printing the stored data and preparing spread sheets in Excel. Flexible graph plotting facility is also available in the software.