The following is a guide on how to clean a swimming pool DE (diatomaceous earth) filter. Written by www.WCPandS.com. The filter in the following example (the photos are from two ProGrid filters on two different days) are Hayward ProGrids. Most other swimming pool DE filters will be similar.
We will also cover common issues that occur during a filter cleaning.
What you need to clean a DE filter:
2 Ratchets
Flat head screwdriver
Hammer (a heavy wrench can be used in place of this)
DE (diatomaceous earth)
Starting:
Turn off the system to ensure the pump will not turn on during the cleaning.
Open the air relief valve to start relieving the pressure inside the filter.
Opening the filter:
Most DE filters are held together with one large metal band (called a clamp assembly) locked with a screw bolt (spring assembly). Remove this bolt with a ratchet.
Note: Do not use a wrench, pliers, or a crescent (adjustable) wrench. Using anything other then a ratchet or socket will break down the brass frame of the screw bolt.
Once the screw bolt is detached, the metal band can be completely removed using a flat head screwdriver.
If the filters inside pressure has equalized the lid (called a filter head) can now be removed.
A flat head screwdriver can be wedged between the top and bottom half of the filter to pry off the lid.
Note: If the gasket has expanded, the lid may be difficult to remove. Multiple flat head screw drivers may be needed on opposite sides of the filter to wedge the top off.
Removing the grids:
Most DE filters have the manifold on top (with the exception of the Pentair 4000 series, which has it at the bottom).
If the grids are not weighted down by excessive amounts of dirt, the grids and manifold can be pulled out as one piece. When doing so, the grids need to be pulled straight up. Only a single pipe (called a outlet elbow) connects the filter base to the manifold. While pulling up sometimes a slight right to left twist is needed to separate the manifold from the pipe.
If the set cannot be pulled out as one piece, remove the nut on the top of the manifold. If the long center bolt (called a Retainer Rod) spins when the nut is unscrewed, a set of pliers can be used to hold the center bolt in place.
Note: Only hold the bolt (Retainer Rod) from underneath the manifold; trying to hold the top end could damage the screw threads, making it impossible to remove nut.
Once the nut is removed, the manifold can be lifted straight up off the grids and Outlet Assembly.
Checking the parts for damage:
-Each individual filter grid needs to be checked for holes. Holes allow for debris to pass freely though the filter system. Any grid with holes will need to be replaced.
-Check the grids for broken ribs. When the system is running, a grid with a broken rib will be forced to press against a neighboring grid. When they press together, it reduces the surface area pulling water in to the system.
-If the connectors that attach the grids to the manifold break, the grid should be replaced. DE and dirt will be able to pass though this area if the grid is placed back in with the connectors broken.
-Check the manifold for cracks. If there are any cracks the manifold should be replaced. Because of the pressure the manifold is under, any cracks could easily worsen and expand when the system is running causing DE and/or dirt to pass back in to the pool.
Cleaning out the inside of the filter:
There is a small drain plug near the bottom of the lower section of the filter. This can usually be unscrewed small screw driver or a pair of pliers. Once this is removed you can now rinse out the inside of the filter. Screw back on the drain plug after the filter inside is cleaned.
Note: This plug is a constant source of leaks if removed and reinserted. Either get a new gasket before removing this plug or have some gasket maker on hand for use on the plug.
Cleaning the girds:
Generally, the filter grids are cleaned simply by hosing then down with water. There are chemicals available for soaking the grids. However, I have never found any difference using these.
Reassembling the grids and the manifold:
This next section can be the most difficult.
Begin by setting the manifold upside down (holes up) on something that keeps it at least 3 inches or more off the ground. You will need to reach under the manifold once the grids are on in to tighten the nut underneath.
The filter grids should be placed one at a time in to the manifold. Match the groves of the grid to the groves of the manifold. They will only go down in one way.
The only small grid will fit in the slot near the manifold opening. This allows for the Outlet elbow to sit next to the grid set in the filter.
Once all grids are placed into the manifold, the circular bottom rack (called a filter element locator) needs to be placed down over the bottom of the grids. The opening of this rack needs to be in the same area as the main hole on the manifold to allow the filter pipe (outlet elbow) to fit in between the grids. Get the center bolt in the rack through the hole in the center of the manifold.
The grids will now need to be organized in order for them to sit properly in the rack. Start with one side and fit each grid in-to the rack. Then, work your way around to the other side. Each grid must fit in to a rack groove. Take note that the pipe can fit along the side of the grids (see picture below) the manifold hold, the rack opening and the grids out of the way to allow the grid set to fit in the filter.
Once all of the grids are in place, tighten the nut on to the long center bolt underneath the manifold.
Turn the grids right side up and then place the set in to the open filter. Line the large open hole of the manifold with the elbow outlet of the filter system. Small twisting motions might be required to get the manifold completely down. (Depending on the age of the filter there is probably a stain all over the elbow outlet pipe except the top area where the manifold normally fits over)
Closing the filter:
When the top of the filter is placed back on, it needs to be pushed down on as evenly as possible.
Note: It is common for the filter gasket to become deformed by either shrinking, making it difficult to stay in position, or enlarging, making it impossible to fit under the lid. It is recommended that the gasket be replaced either case; if the gasket is to small water may get though when the system runs, causing a leak.
If the lid cannot be pressed down completely, then using a silicon lube on the gasket may help. If the lid can be lowered enough to get the band close to being on, then screwing in the bolt to the band will automatically pull the lid down further.
The band may need to be lightly hammered around the frame while you re-tighten the screw bolt intermediately to ensure the lid is secure.
Restarting the system:
Note: This next part is potentially dangerous. Staring up the pump while the filter top is not fastened down could cause the lid to be blown off and injure you. Double check that the band is in place and properly tightened. Proceed with caution.
With the air valve open, turn back on the pump. Once the system restarts and all of the air blown out of the filter, close the air valve and turn off the pump. The system will pull the filter lid further down. Check the band screw bolt to see if it needs to be further tightened.
While the system is running, check for leaks around the band. If you find that it is leaking, check that the band screw bolt is as tight as you can safely get it. The filter gasket may need to be replaced if there is still a leak from this area.
Wine Country Pools & Supplies is not responsible for any damaged caused from the use of this guide.
Wine Country Pools & Supplies is not responsible for any damaged caused from the use of this guide.