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Filter Backwash:

When the filter is precoated the first time, the pressure indicated on top of the unit should be noted and recorded.  A new "clean pressure" should be recorded and used as the baseline for filter operation following each backwash and precoat.

Remember that the purpose of the filtration system is to remove particulate matter including, small pieces of trash, that passes through the strainer baskets.  The system also removes material like dead algae and other solids that can't be see with the naked eye but causes cloudy water.  Over time, with the accumulation of the foreign and "invisible" matter, the pressure required to force water through the filter leaves increases.  If the system were used for an extended period of time without regard for the increase in inlet pressure, circulation failure or damage to the filter leaves could occur.  Removing material accumulated on the surface of the filter internals is called backwashing and the procedure should be utilized once the filter inlet pressure reaches a point 8 to 10 pounds higher than the pressure recorded at the onset of the filtration period.

As the name implies, backwashing involves reversing flow through the filter with the backwash material going to the sewer through the pool waste line. 

  1. Shutdown circulation pumps.

  2. Turn the filtration valve from the "filter" position to the "backwash" position by depressing the large handle until the position holding tab clears the slot that holds it in position.  The large handle is plastic so just apply adequate pressure to cause the tab to clear the ledge that holds it in place.  Applying excessive pressure to the handle can result in damage to the unit.

  3. Start the main circulation pumps and observe the sight glass on filtration valve body.  When the backwash begins, the contents of the glass will change from clear to very cloudy.  After a couple of minutes, the water will become clear again.

  4. Once the water becomes clear, shutdown circulation and wait 5 minutes.

  5. Restart circulation and observe the sight glass again.  This time the duration of flow with cloudy material will be shorter.  Keep repeating steps 2 and 3 until the contents of the sight glass doesn't change when the pump is started or a maximum of 4 times.

  6. Now, shutdown circulation and move the filtration valve back to the filter position using caution explained in step 1.

  7. Start circulation pump in preparation for precoating the filter.

  8. Remove the cover from either of the skimmer wells and add 10 scoops of diatomaceous earth to the water stream.  The water stream flows to the circulation pump then through the filter where the diatomaceous earth covers the filtration leaves. 

  9. Replace the cover to the skimmer wells, be sure to record the "clean" inlet pressure to the filter and backwashing shouldn't be required again for approximately 3 months with average use.



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Filtration Sight Glass  Back To Procedure

Remove Skimmer Cover                                Back To Procedure