HOW TO BACKWASH A DE FILTER

 
 
 
 

Backwashing a DE filter is a relatively simple process if you follow a few quick and easy steps. Let's take a look at WHY, WHEN, and HOW to backwash a DE filter with a multiport valve.

WHY

A Diatomaceous Earth (DE) Filter cleans your pool by utilizing DE powder and (usually) eight grids. Each grid has a plastic framework, covered with a tough but fine mesh. DE powder covers the outside of the fine mesh, allowing only water to pass through. The DE powder is the filter media and is what filters particles out of the water. Flow-through to the grid is from the outside to the inside. As water passes through your grids, it leaves behind dirt, residue, oils, etc. Over time with the water flowing in only one direction, your filter media becomes clogged to the point where your water flow will decrease. The purpose of backwashing is to reverse the flow of water which will 'blow out' the old DE so that it can be replaced with clean DE.

WHEN

Look out for these top two signs it's time to backwash:

  1. INCREASE IN PSI - PSI (pounds per square inch) is the measure of pressure that your filter is operating on. You'll know it's time to backwash when the filter's pressure gauge rises 8-10 psi over its normal baseline.

  2. DECREASE IN WATER CLARITY - If you notice your pool water is a little cloudy or see debris floating that the filter doesn't seem to be capturing, it could mean the filter isn't working as well as it should.

HOW

  1. Make sure you have enough DE on hand - You will need about 4-6 pounds of DE to replace the old DE powder.

  2. Turn the pool pump OFF 

  3. Turn the multiport valve to the BACKWASH position, making sure that the handle is locked in place.

  4. Hook up your backwash hose and place it where you want to dump the wastewater.

  5. Turn the pool pump ON and run the pump for 2-3 minutes. The water in the sight glass will change from cloudy to clear.

  6. Turn the pool pump OFF

  7. Turn the multiport valve to the RINSE position, making sure that the handle is locked in place.

  8. Turn the pump ON and run the pump for 15-30 seconds.

  9. Turn the pump OFF

  10. DE powder can be stubborn, so for good measure repeat steps 3-9 one to two more times (Backwash at least twice) 

  11. Turn the pump OFF

  12. Turn the multiport valve to the FILTER position, making sure that the handle is locked in place.

  13. Turn the pump ON

  14. Mix the appropriate amount of DE powder with water to create a slurry and pour directly in the skimmer closest to the pump. The DE will be drawn to the filter and distributed evenly over the grids. Let the pump run for at least 30 minutes.

  15. Check the filters pressure gauge and confirm that the pressure is at your normal baseline.

These are the basic steps to backwash your DE filter, but you could have a different set up than described here. If you have any questions about backwashing, let us know!

 

/ HAPPY SWIMMING /




Pool MaintenanceElizabeth JohnsonDE Filter, DE