Never vacuum your pool with the filter set to backwash mode - this sends debris directly to waste and can damage your equipment. Use the Filter setting for normal vacuuming or Waste setting for heavy debris.
You should not vacuum your pool with the multiport valve set to backwash under normal circumstances. This setting is designed to reverse water flow through your filter media to clean it, not to handle incoming debris from vacuuming. Using backwash while vacuuming can damage your filter system and won't effectively clean your pool.
Before diving into the proper vacuuming technique, let's clarify what each valve setting does:
For regular maintenance vacuuming, set your multiport valve to Filter. This allows debris to be captured in your filter media while returning clean water to the pool. If you're dealing with heavy debris or very dirty water that might clog your filter quickly, consider using the Waste setting instead.
Connect your vacuum head to the telescopic pole and attach the vacuum hose. Submerge the vacuum head and slowly feed the hose into the pool until it's completely underwater and air bubbles stop emerging. This ensures proper suction.
Connect the free end of the vacuum hose to your skimmer suction port or dedicated vacuum line. You should immediately feel strong suction at the vacuum head.
Move the vacuum head slowly across the pool bottom in overlapping strokes. Rapid movements will stir up debris and reduce cleaning effectiveness. Work systematically from the shallow end to the deep end.
Keep an eye on your filter pressure gauge while vacuuming. When pressure rises significantly above the clean starting pressure (typically 8-10 PSI, but verify your manufacturer's recommendations), it's time to backwash your filter or clean your cartridges.
Consider switching to the Waste setting when:
Remember that using the Waste setting will lower your water level since you're sending water directly to the drain. You'll need to add fresh water to compensate.
Using Backwash: This is the most critical error. Backwash reverses water flow, which means debris from your vacuum would flow backward through your filter and potentially damage the internal components.
Vacuuming Too Quickly: Moving the vacuum head rapidly creates turbulence that suspends debris in the water column rather than capturing it.
Ignoring Filter Pressure: Continuing to vacuum with a dirty, high-pressure filter reduces suction effectiveness and can strain your pump motor.
Skipping the Rinse Cycle: If you backwash during your vacuuming session, always run a brief rinse cycle before returning to Filter mode to settle the filter media properly.
After completing your vacuuming session, you'll likely need to clean your filter system. For sand and DE filters, this means backwashing followed by a rinse cycle. For cartridge filters, remove and rinse the cartridges thoroughly. This maintenance step is crucial for maintaining proper water circulation and filtration.
If you used the Filter setting and notice your water has become cloudy during vacuuming, this indicates your filter media needs attention. A properly functioning filter should capture debris without allowing it to return to the pool. Consider consulting our comprehensive filter guide to ensure your system is operating optimally.
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