When a pool’s filter is clogged with debris, backwashing may be necessary. In this process, the filtering system’s valves are repositioned, reversing the water flow through the filter tank, so that all trapped material on the filter media is dislodged and carried to waste.

The pool water travels through the tank and out to waste or sanitary sewer, leaving the filter grids, elements or sand intact and clean. Backwashing is typically recommended when a pool’s pressure gauge reads eight to 10 pounds above the clean or startup pressure. Since the water will flow through the drainage hose, be sure that it is positioned correctly — in a grassy area or sewer drain — according to your locale’s regulations. Run the backwash for about three minutes.

Check the clear reservoir of water on the outside of the filter. When it is no longer cloudy, turn off the filtration system and return the valves to the rinse position for a few moments. Finally, return the system back to its filter position and check the return valve. If the flow of water is steady and strong, the backwash was successful. Because water is removed from the pool, check the water level and be sure to add water if necessary.