Consider the stirred-tank heating system of Section 2.4.1 with constant holdup and a steam heating coil. WE assume that the thermal capacitance of the liquid condensate is negligible compared to the thermal capacitances of the tank liquid and the wall of the heating coil. This assumption is reasonable when a steam trap is used to remove the condensate from the coil as it is produced. As a result of this assumption, the dynamic model consists of energy balances on the liquid and the heating coil wall: