Thermic Fluid Heater is most popular in almost every industry, and it is being used for various heating applications due to unique advantage over other heating systems like steam heating, electrical heating, direct firing, air heating etc. In many of the applications, it is very cost effective and energy saving as it has an exceptional advantage over other industrial heating methods. Thus, it is important to recognize various aspects of thermic fluid heating and significance of thermal oil temperature when thermic fluid circulate through tubes of heater. When fluid flowing inside the coils or tubes of the heater, it creates multiple layers of flow of the fluid along the tube periphery and this layer is almost stationery in a form of a film. This formation of film offers very high resistance to flow of heat from the heat source through heated metal surf...