Filtration & Circulation /
How to Clean a Pentair Pool Filter Safely
Clean a Pentair pool filter by identifying the filter type, shutting off the pump, removing trapped debris, and following the owner’s manual for reassembly and restart.
Archive date: this article was written for PoolSkimmer on Oct 23, 2026 and given the earlier archive date of Jun 11, 2026 so the blog reads as an organized archive. It was not published on that date.
Cleaning a Pentair pool filter
The first step in cleaning any Pentair pool filter is to determine if you are dealing with a cartridge, sand or DE unit. Once the type is known, put down the tools and consult the owner’s manual for that particular model. It is imperative to turn off the pump before you open anything up. Should you come across a part that is cracked, leaking or otherwise stuck, the prudent thing to do is leave it be and contact a pool professional.
Pre-cleaning checks
A quick look over will tell you if the filter is in need of service or just routine cleaning.
1. Verify the filter type from the label or your paperwork. 2. See what the pressure gauge is reading; an above normal number is cause for attention, though it does not in itself dictate how to clean it. For that, stick to the Pentair manual and do not guess. 3. Note any cloudy water or a return flow that seems weak. 4. Don’t touch the skimmer basket or the filter until the pump is off. 5. Put on some PPE, gloves and eye protection are advisable when you have to handle soiled parts.
The cartridge filter
With a Pentair cartridge, the idea is to get the debris out of the pleats without causing harm to them. You can do this by taking the cartridge out and giving it a good rinse with the hose.
Proceed in this order: - As the manual says, relieve the pressure and shut the pump down. - Be careful opening the housing and take out the elements. - Run the hose over them from top to bottom, in between the pleats as well. - Give the end caps and pleats an once-over for any tears or collapse. - Put everything back in place per the instructions.
If a rinse does not seem to clear a clogged cartridge, the manual may have a more involved procedure. Resist the urge to concoct a soak with chemicals of your own making.
Sand and DE filters
These require a different approach than a cartridge. Depending on the model, you may be looking at a backwash, a rinse or even some disassembly.
Check the manual for what is called for and turn the pump off prior to working the valves or tank. If the model requires a backwash or rinse sequence, follow it. The same goes for the removal and reinstallation of a DE grid assembly. Under no circumstances should one try to work with live suction or put hands into the outlets. When in doubt as to whether a full teardown is necessary, verify with the instructions first.
Pitfalls to steer clear of
Some errors are worse than the dirt you are trying to remove. Do not open the filter with the pump running, and don’t force a lid or clamp. Reusing an O-ring or seal that has seen better days is another mistake, as is skipping the priming or restart procedures. And while they may look alike, do not treat every Pentair model in the same fashion. If there is a crack in the tank or you suspect an electrical issue, this is beyond routine maintenance.
Time to call in an expert?
There is no need to be a hero. If the filter is uncooperative, or if you see damaged plumbing, repeated leaks and cracks, get a qualified professional. The same applies if the water flow is still poor after you have done your work, or if the assembly does not seem safe to handle.
In short: identify the unit, kill the power to the pump, let the Pentair manual guide your cleaning and inspection of the parts, and only restart when told to.
Sources and further reading
- [Hayward: Weekly pool maintenance](https://www.hayward.com/maintenance/weekly-pool-maintenance)