How To Backwash a Hayward DE Filter Grid Assembly

This guide shows you the steps required to the procedure for the second level of cleaning the grid assembly. Periodically you have to clean the debris and contaminants out of your Hayward DE Filter. This process can be done at three levels: 1- by backwashing the filter; 2- by extracting and cleaning the grid assembly; or 3- by extracting and cleaning each grid in the assembly. For a more thorough cleaning, you can extract and clean the grid assembly.   For the most thorough cleaning, you can pull the Grid Assembly and take it apart to wash down each Grid individually. This third level of cleaning is generally done once a year at the end of the season.

1. GATHER TOOLS - Pull together the tools you will need: a socket wrench, a large open ended wrench, silicon or Teflon based lubricant, a rubber mallet,  a face mask and a cleaning cloth.

2. TURN OFF POWER - If your pump is on, turn it off at the power switch or ideally at the circuit breaker box.

3. OPEN AIR RELIEF VALVE - Release the pressure in the filter tank by opening the air pressure relief valve at the rear of the pressure gauge.

4. REMOVE DRAIN PLUG - Remove the drain plug to drain the filter. Insert a screwdriver into the slot of the plug to work as a lever if the plug cannot be removed by hand.

5. VIEW CLAMP ASSEMBLY - The tank of this Hayward DE Filter is split between an upper and a lower section held together in the middle by a Clamp Assembly. To open up the tank, you will have to remove the Clamp Assembly.

6. UNSCREW HEX NUT AND BOLT - The Clamp Assembly is secured with a nut and bolt. Put a socket wrench on the head of the bolt and an open end wrench on the nut and unscrew the bolt. - counter clockwise.

7. REMOVE HEX NUT AND BOLT - With the nut off, remove the bolt from the Clamp Assembly.

8. LOOSEN CLAMP - The Clamp Assembly is pressed on tight. Tap one end of the Clamp with a rubber mallet to loosen the Clamp Assembly.

9. REMOVE CLAMP - Take the Clamp Assembly off of the tank. Note there are two pivots or hinges on the clamp to help to remove or replace the clamp.

10. LOOSEN TANK HALVES - The two halves of the filter tank may still be stuck together. Take a rubber mallet and gently tap the top sides of the upper tank.

11. LIFT OFF TOP HALF - Lift the upper tank section straight up off the grid assembly.

12. VIEW GRID ASSEMBLY - This is a picture of the top half of the grid assembly. Note the 8 grids covered with DE Powder.

13. HOSE DOWN GRID ASSEMBLY - To reduce the weight of the grid, hose down the grid assembly to strip off most of the DE Powder.

14. REMOVE GRID ASSEMBLY - Lift the Grid Assembly straight up out of the Filter Tank. As you lift it off, the Manifold Pipe on the side of the Grid Assembly should separate from the bottom pipe on the tank. Note how they line up so you can connect them when you replace the Grid Assembly.

15. HOSE DOWN GRID ASSEMBLY AGAIN - Place the Grid Assembly on the ground and hose it down again. Spray down inside the Assembly as well and outside to remove as much of the old DE Powder as possible.

16. HOSE OUT TANK BOTTOM - Hose out the bottom of the tank. The water and debris should flow out of the drain.

17. REMOVE AND INSPECT TANK O-RING - Pull out the Tank O-ring laying on the edge of the bottom section of the Tank. Inspect to for cracks and wear. Replace if the Tank O-ring necessary.

18. CLEAN O-RING SLOT - Clean off the slot where the Tank O-ring lays.

19. REPLACE TANK O-RING - Replace the Tank O-ring.

20. LUBRICATE TANK 0-RING - Lubricate the top of the Tank O-ring with a silicon or Teflon based lubricant.

21. REPLACE GRID ASSEMBLY - Drop the Grid Assembly back into the bottom section of the Tank. Make sure the sections of the Manifold Pipe line up.

22. HOSE OUT TANK TOP - Clean out the top section of the Tank.

23. REPLACE TANK TOP - Place the top section of the Tank back on top of the Bottom section. Make sure the Pressure Gauge is lined up so you can see it.

24. SEAT TANK TOP - Push down on the top of the Tank with a rocking motion to help seat the Tank top.

25. REPLACE CAMP ASSEMBLY - Replace the Camp Assembly starting with the back third and folding the two sides to the meet at the front. Make sure the clamp is positioned over both lips of the upper and lower tank sections.

26. REPLACE CLAMP BOLT AND NUT - Insert the bolt and begin screwing the nut on the end of the bolt.  Stop to adjust the Clamp Assembly when the nut becomes hard to turn.

27. ADJUST CLAMP ASSEMBLY - Gently hit the Clamp Assembly around its circumference to seat the Clamp further. Retighten the bolt assembly. Do this adjustment a couple of times. Make sure the final twists are snug but do not overtighten the bolt assembly.

28. REPLACE DRAIN PLUG - Replace the Drain Plug at the bottom of the Filter Tank.

29. CHECK MPV IN FILTER POSITION - Ensure that your filter's Multiport Valve (MPV) is set on FILTER mode.

30. TURN ON PUMP -Turn the pool pump ON and let it reach prime.

31. CLOSE RELIEF VALVE - The Air Relief Valve should be open to initially let air out of the top of the filter. Close this valve when a steady stream of water shoots out the end of the valve.

32. ADD DE POWDER - Go to our guide on "How To Use DE Filter Powder".

If you have any other questions about pool and spa products please do let us know - we are here to help!

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