Pool care articles
When to clean a pool filter: check the gauge
Clean a pool filter when the gauge, read at the same pump speed and setup, has risen above its recorded clean starting pressure by the amount your model’s manual gives, or flow has dropped significantly. Pentair’s Clean & Clear Plus guide uses approximately 10 psi above the original pressure. Sullivan’s Pool Service in Austin records that clean pressure every time we clean a filter.
A pool filter needs cleaning when its pressure gauge, read under the same conditions as before, has risen above the filter's own clean starting pressure by the amount the manual for that model gives, or when the flow has dropped significantly. The date on the calendar does not decide it. If you own a pool in Austin, the gauge on your filter and the manual that came with it are the two things to go by.
Start from a clean baseline
Every filter has its own normal. The number worth knowing is the pressure the gauge shows right after that filter has been cleaned. When we clean a filter, we record that clean starting pressure, so the next decision is judged against this filter rather than a rule of thumb or a number from someone else's equipment.
Read the gauge the same way each time
A pressure reading only means something next to the baseline when the conditions match. Compare the gauge at the same pump speed and the same operating setup you had when the clean reading was taken. A reading taken at a different speed or with a different setup is not the same comparison.
Follow the manual for your model
The cleaning point is set by the manufacturer of the filter you actually have. For its Clean & Clear Plus cartridge filter, Pentair says to clean at approximately 10 psi above the original starting pressure, or when there is a significant reduction in flow. Some other Pentair cartridge models call for cleaning at about 8 to 10 psi above their starting pressure. Those are instructions for those models. They are not one setting for every filter, so check the manual for yours.
Debris and use change how quickly a filter loads up. That is why a calendar alone cannot tell you when cleaning is due, while the gauge and the manual can.
Know which filter you have
Cartridge, DE and sand filters use different filtering material, and each is serviced differently. A cartridge filter uses pleated elements. A DE filter uses a coating of diatomaceous earth. A sand filter uses a bed of media. Identify yours from the label on the filter, not from the shape of its tank, because the cleaning and recharge steps depend on the model.
What our filter cleaning includes
We clean cartridge, DE and sand filters. For a cartridge filter we pull the cartridges and open and rinse the pleats one by one, rather than hosing each element as a block. For a DE filter we strip and clean the grids and weigh the correct charge back in. For a sand filter we backwash and rinse, and we report the condition of the media instead of assuming it. While the housing is open we check the O-rings, the clamps and the pressure gauge itself, and we record the new clean starting pressure for next time.
Leave opening the filter to qualified service
A pool filter can be under pressure. The manual carries pressure and safe-servicing warnings, and opening a pressurized system takes the proper procedure. It is a job for qualified service, done with the manual for that model in hand.
Pressure is not a water test
Restricted filtration can contribute to cloudy water, but cloudy water does not point to a single fault. We check the water results and the circulation system together to find the cause. A pressure reading tells you about the filter. It does not show that the water is disinfected, and clear water alone does not prove it is safe to swim. So we read the gauge and the water test results side by side, and neither one stands in for the other.
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Where Sullivan’s works
Sullivan’s Pool Service maintains pools in and around Austin, including Northwest Hills, South Austin, West Lake Hills, Tarrytown, Great Hills, River Place, Crestview, East Austin, North Austin, West Campus, Hyde Park, Downtown Austin and St. Johns, and in Bee Cave, Cedar Park, Georgetown, Leander, Pflugerville and Round Rock. See every service area.
Weekly residential service has one fixed monthly price, set by pool size: see pool service pricing for what each size tier covers.
Tell us about your pool
Tell us your service location and whether you need weekly care, help with equipment, or a one-time service. Call or send the quote form. We’ll confirm availability and the next step for your pool. Repairs and other separately quoted work are discussed before approval.