Steam enters the condenser where it cools and condenses into water before being sent to the low-pressure feed-water heater. The condenser hotwell serves as a water reservoir for the turbine cycle. When hotwell level reaches the low point, a valve opens to supply make-up water to the cycle. When hotwell level reaches the high end of the level range, a dump valve opens to move the condensate from the hotwell to a condensate storage tank.
Water loss in the turbine cycle due to leakage, steam venting or other usage depletes make-up water. Level control in the hotwell ensures adequate make-up water is supplied to the cycle or diverted to storage.