Cleaning Pool Filters

CLEANING A FILTER

Sand Filter
DE Filter
Cartridge Filter

CLEANING A SAND FILTER:

If you have a sand filter, it will need to be backwashed when the pressure is 8-10 psi above the standard operating pressure. Here are the steps:

  • Turn "off" the equipment.
  • Move the multiport handle from "filter" to "backwash".
  • Turn "on" the equipment.
  • Allow the equipment to backwash for 2 - 3 minutes. If your filter is equipped with a sight glass, backwash until the water in the sight glass turns from dirty to clean. When you backwash, you will sacrifice some of your pool water-chlorinated (or its alternative) pool water. Monitor the level of your chlorine (or its alternative) after a backwash. Also, monitor the water level. If it gets low, add water until the water level is at least half way up the skimmer.
  • After backwashing, turn "off" the equipment.
  • Move the multiport handle from "backwash" to "rinse".
  • Turn "on" the equipment.
  • Rinse the sand for 20 - 30 seconds to assure that all dirt and debris has been eliminated from the fresh sand.
  • Turn "off" the equipment.
  • Move the multiport handle from "rinse" back to "filter".
  • Turn "on" the equipment and operate as normal.

Notes:
Sand should be professionally replaced every 4-5 years. After this 4-5 years, once filter cycles decrease (when it is taking less time for the pressure gauge to show a rise of 8-10 psi) and the need for backwashing increases, contract your local pool professionals and pay them to change the sand. There are fragile laterals at the bottom of the inside of your sand filter. If even one of these laterals is cracked or broken, sand will enter the pool, resulting in additional service-and additional fees. Therefore, have the sand professionally replaced.
You can prolong a filter sand change by adding a specially formulated Sand Filter Cleaner during the 3rd or 4th year. Read the instructions on the label before adding any chemical/cleaner.
Poor water chemistry, as well as insufficient cleaning of the filter, can lead to problems with the sand. Mud balls may form due to poor water chemistry, particularly a high pH. If your water is high in pH, it will not be able to keep calcium in solution. This calcium will find its way into the filter. This calcium can attach to the sand and combine with hair, lint, and other debris (due to a poorly cleaned filter) and form the mud balls, which can again attach to other mud balls to form even larger mud balls, resulting in a blockage in the filter. This can further lead to calcification of the sand. Another potential problem is channeling. If water chemistry or filter cleaning are further neglected, channeling may occur, creating a trail through the sand. During filtration, water will pass through the filter, but the dirt and debris will make its way through the channel, never coming in contact with the sand, and will re-enter the pool. Monitor your water chemistry and clean your filter.

CLEANING A DE FILTER:

If you have a DE filter, it will need to be backwashed when the pressure is 8-10 psi above the standard operating pressure. The main drawback of backwashing with DE filters is that as the dirt and debris are removed from the filter, so is the DE powder. This requires adding new DE powder after each backwash. New style DE filters, called Regenerative DE filters, have implemented a "bump" mode in order to prolong the filter cycles and reduce the need to backwash. But, after so many "bumps," backwashing is inevitable. Here are the steps:

  • Turn "off" the equipment.
  • Move the multiport handle from "filter" to "backwash"
  • Turn "on" the equipment. Allow the system to backwash for 2-3 minutes. If your filter is equipped with a sight glass, backwash until the water in the sight glass turns from dirty to clean. When you backwash, you will sacrifice some of your pool water-chlorinated (or its alternative) pool water. Monitor the level of your chlorine (or its alternative) after a backwash. Also, monitor the water level. If it gets low, add water until the water level is at least half way up the skimmer.
  • Turn "off" the equipment.
  • Move the multiport handle from "backwash" to "rinse."
  • Turn "on" the equipment.
  • Rinse the new layer of DE powder for about 10 seconds to assure that all dirt and debris have been removed from this new DE powder.
  • Turn "off" the equipment.
  • Move the multiport handle from "rinse" to "filter."
  • Turn "on" the equipment.
  • Add new DE powder
  • Mix DE powder in a bucket of water, following the manufacturer's directions.
  • Pour the DE powder/water mixture into a skimmer. The mixture will enter the DE filter and disperse evenly to create a fresh layer of DE powder on the DE grids. The DE powder forms what is called a filter cake on the grids.
  • Too much DE powder can cause the filter cake to be too thick. The grids will compress against each other, casing an adhesive of the dirty DE powder to the grids. If this occurs, you would be wise to contract and pay your local pool professionals to scrape the dirty DE powder off the grids; care must be taken so that the grids are not torn.
  • Too little DE powder can cause dirt and debris to get imbedded on the grids, which will ruin the grids.

Notes:
New style DE filters, called Regenerative DE filters, require less backwashing, as they can be "bumped" to readjust DE powder, which prolongs the filter cycle. Here are the steps to "bumping":
When the pressure is 8-10 psi above the standard operating pressure, close all the valves (main drain and skimmers) and turn the equipment "off" for at least 2-3 minutes
Most Regenerative DE filters have a "bumping handle." By slowly pulling down and rigorously pushing up on the handle 5-10 times, DE powder will fall to the bottom of the filter
When 5-10 bumps are completed and 2-3 minutes have elapsed, open all of the valves and turn the equipment back "on", and a fresh layer of DE powder will instantly form on the DE grids inside your DE filter.
A Regenerative filter can only be bumped so many times before backwashing is inevitable. Once filter cycles decrease and the need to "bump" increases, backwash the filter and add new DE powder, using the same sequence of steps as above.
If your Regenerative DE filter is not equipped with a "bump handle," simply hit the actual filter tank/body with a rubber hammer 5-10 times.
Check the DE grids inside your DE filter periodically. Cleaning the grids is required periodically because (body or suntan) oils, scale, and other deposits can build up on the grids. Many pool professionals sell a specially formulated Filter Cleaner for DE grids. If the grids are torn or frayed, have your local pool professionals install new DE grids for you.

CLEANING A CARTRIDGE FILTER:

If you have a cartridge filter, the individual pleated filter elements will need to be removed from the filter itself, cleaned with a garden hose and pressurized nozzle when the pressure is 8 - 10 psi above the standard operating pressure, and secured back in the filter. There is no backwashing with a cartridge filter. Here are the steps to clean a cartridge filter:

  • Turn "off" the equipment.
  • Remove the lid to the filter tank. Many Cartridge filters have a band that holds the lid of the filter to the base of the filter. If your cartridge filter uses a different application, or if you have difficulty removing the lid for any reason, consult your local pool professionals for advice.
  • Remove the pleated filter element(s) from the filter. Some cartridge filters use only one large pleated filter element, while other cartridge filters use a series of smaller pleated filter elements.
  • Spray each pleated filter element with a garden hose and pressurized nozzle. Take time to spray between each pleat, as this is where dirt and debris will collect.
  • Put the filter element(s) back in the filter.
  • Put the lid back on the filter tank and secure the lid. Make sure the large O-ring is in place and is in good working shape. About once per month, or whenever needed, put an O-ring lubricant on the O-ring. This will create a tight seal, eliminating any air from entering the filter. This will also extend the life of your O-ring. If the O-ring is torn or frayed, or in any way unusable, then purchase a new O-ring from your local pool professionals.
  • Turn "on" the equipment and operate as normal.

Notes:
The individual pleated filter element(s) should be replaced yearly. A benefit of cartridge filters is their filtering capabilities and the ease in which they are cleaned. A drawback of cartridge filters is the expense of replacing pleated filter elements each year. But, if the pleated filter elements are still in relatively good shape, store them and keep them as a backup while your main pleated filter element(s) are being cleaned.
You can prolong the life of pleated filter elements by soaking them overnight in a specially formulated Cartridge Cleaner every 3-4 months. You will, however, need backup pleated filter elements to install in your filter while your main pleated filter elements are soaking overnight. Read the instructions on the label before placing your pleated filter elements in a (5-gallon) bucket with a mixture of the Cartridge Cleaner and water.
If pleated filter elements are torn or if the base is cracked, new pleated filter elements will need to be purchased, even if it they are less than 1 year old.