How to Backwash a Sand Filter
- 1). Connect a pool hose to the backwash valve and lead it toward the drain of your yard. Shut the filter off and turn the dial valve near the bottom of the filter to the "Backwash" position.
- 2). Turn the filter on. The water will now drain from the backwash valve. Let the filter run for about one minute until the water runs clear from the filter. At first the water will come through the filter clear, and then dirt and debris of the filter will follow.
- 3). Turn the filter off again and rotate the dial to the "Rinse" position. Turn the filter back on and let it rinse for 30 seconds. This will allow the filter to ready itself again for basic operation as the sand is compacted. Turn the filter off.
- 4). Rotate the dial to the "Filter" position. Turn the filter back on and resume normal operation. Check the filter pressure gauge. It should now read between 15 and 20 psi. Many sand filters will have a green area that indicates safe filter pressure.
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