How to backwash a sand filter

We will show instructions on how to backwash a sand filter.

  • Turn off the pump and rotate the multiport valve to backwash
  • Then turn the pump back on and let the pump run on backwash for a few minutes, you'll see the sight glass become dirty and eventually start clearing up.
  • Turn the pump back off and change the multiport on top of the filter to rinse.
  • Perform the rinse function for anywhere between 15-30 seconds to finish cleaning the sand. Again turn off the pump before moving the multiport valve to filter.
  • After completing the rinse step, the pump can be turned off and the valve can be switched back to filter.

It is recommended that the pump is turned off when changing settings on the multiport valve. Changing multiport settings with the pump running can cause damage to the internal filter components.

Here is a brief overview of when a sand filter requires backwashing. Often a filter is backwashed after vacuuming, or before a adding clarifier or flocculant.

  • Often backwashing is necessary when the pressure gauge is reading near or above 20psi.
  • If backwashing does not reduce the pressure to between 10-15 psi, there further backwashing may be required, or more troubleshooting is necessary.
Pools, CleaningEarl WalkerThe Handy Family, Inc.Sand Filter, Backwashing