How to backwash a filter

Backwashing is a maintenance process used for sand and DE filters. It reverses water flow to flush out trapped dirt and debris. To backwash, turn off the pump, set the valve to “backwash,” and run the system until the water in the sight glass turns clear.

After backwashing, switch to “rinse” for 20–30 seconds, then return to the standard filtration setting. Professional Pool Company recommends backwashing when filter pressure rises 8–10 PSI above normal.

Updated on: 27/11/2025