While D.E. filters offer the best possible particulates and debris removal (down to 8 microns) it does come with more extensive maintenance criteria.
Backwashing your filter
It is recommended to backwash your D.E. filter when the pressure reading on the tank rises to 5-8 lbs above normal or once a month, whichever comes sooner. If your DE filter pressure reading requires a cleaning prior to monthly cycle then it may be time for a breakdown and full cleaning. A breakdown and full cleaning is recommended at least once per year or more.
How to backwash your D.E. filter
Clean all the debris from the skimmer basket and filter pump basket. Remove all debris that might be trapped around the main drains such as leaves, sticks and toys. If you don’t remove this debris then it is possible the backwashing process might cause these items to force back into your pool. Normally, this will occur when you are using a separation tank that discharges the water back to the pool (after removing the D.E.) Make sure you have turned off the power to the system and proceed as
- If you have a shut off valve in the backwash discharge line make sure it is in the open position.
- Turn your backwash lever to the slot marked “Backwash”. Turn on the pump and let it run until the discharged water looks clean and absent of any D.E. You should be able to view the water clarity through the sight glass.
- Turn the pump and system off and turn your backwash lever back to the slot marked “filter” Turn the pump and system back on.
- The next step is to add new D.E. back into your system. With the system running, place the appropriate amount of D.E. into the skimmer suction port. (NOTE: make sure your skimmer suction is running. Some pool systems allow you to change the valve position between main drains and skimmer) Make sure you sift the D.E. into your skimmer at a rate that does not overflow the skimmer area and cause the D.E. to spread all over the place and get into the swimming area of the pool. To determine how much D.E. to use, the rule of thumb is about a pound of D.E. for each 12 square feet of filter surface area. Example: 60sq’ D.E. filter divided by 12 = 5 pounds of D.E. that will need to be added.
NEVER move the backwash valve while your pump is running! Make sure the pump and entire system (for added safety) are in the off position. It might be a better idea to turn the pool system breaks off just in case you have an automated system that could activate the system (due to its programming) while you are servicing it. Serious injury or damage to the system can occur if you do not follow this warning.
Breakdown and Cleaning of your D.E. Filter
If the DE filter goes less than 3-4 weeks between backwashing on a home pool, then it may be time for a DE filter clean. Most filter manufacturers recommend that the DE clean should be done 1-2 times per year. The filter cleaning process is as follows:
- First, backwash the filter per the instructions under Backwashing Your Filter
- Open the air relief valve located at the top of your filter tank as to release the vacuum and allow the water to drain from the tank. (you should start to hear a slurping noise)
- After all the water has drained from the filter tank, remove the nut/bolt holding together the strap in the middle of the tank. Remove the strap and then remove the top half of the filter tank.
- Remove the entire filter grid assembly. It could be a little heavy so you might need some help.
- Remove the individual filters from the assembly.
- Using a garden hose wash down each piece, removing all the D.E. stuck onto the elements together with the dirt.
- Inspect all the elements for tears and damage. If you find a tear, hole or damage then you will need to replace that item. It can be purchased separately here
- Remove all the remaining waste and debris from the bottom half of the filter tank. Completely clean out the filter tank. Wipe clean the large “O” ring that was sandwiched between the two halves of the tank. If the “O” ring is getting dry you might have to lubricate it using the approved lubricant.
- Reconnect the filter elements to the main grid; place the grid assembly back in the filter tank in the same manner in which it was removed.
- Place the “O” ring on the grooved area between the two halves of the tank, mount the top half of the tank and reconnect the strap. As a general rule, you should tighten the nut/bolt assembly until the gaps between the spring close. There should be a spring between the nut and bolt assembly in most models.
- Congratulations! You are now ready to start the system back up put fresh D.E. in. Follow the D.E. replacement instructions under Backwashing Your Filter, Section #4