A remote sump configuration protects the basin water from freezing. Using a remote sump also allows the equipment to be run in fan-only operation without going through the process of draining the sump. However, the amount of water in suspension associated with each condenser can affect the size of the sump and, therefore, the cost of the project.
Cold-weather operation of evaporative condensers tends to allow long periods of pump-only operation. During pump-only operation, water exiting the spray headers will induce airflow downward through the unit. This movement of air and subsequent pressurization of the condenser will force water vapor out through the air intakes, thereby bathing the fan wheels of forced draft centrifugal fan condensers. This water vapor will be prone to form ice in cold weather, impeding fan operation — a scenario to be avoided in all cases.