This video shows how to build a working model of a cross-flow, one pass, shell and tube heat exchanger for the purpose of analyzing the heat transfer coefficient of the design as well as the tube and shell side pressure drops. In this model, two separate fluids at different temperature pass through the heat exchanger, flowing in opposite directions. In the shell of the heat exchanger, air enters at a velocity of 1m/s and a temperature of 5°C. Water enters the tube side with a velocity of 0.1 m/s and a temperature of 80°C. A k-epsilon turbulence model is used to analyze both the air and water flow profiles. The separating conducting material is assumed to be structural steel. The solution is checked for accuracy by analyzing the upside wall lift-off, which indicates that the model is accurate enough for the purpose of our analysis.