Pentair Clean & Clear Plus: High Filter Pressure — Cleaning and Replacing Cartridges

Cartridge filters work differently from DE and sand filters — they have no backwash valve. When pressure rises, the only resolution is to remove the cartridges and physically clean or replace them. The Clean & Clear Plus manual specifies cleaning when pressure is approximately 10 psi above the starting baseline, and it prescribes a three-level response: hosing, soaking in filter cleaner, and replacement. Each level addresses a different type and degree of cartridge fouling.

When to Clean the Cartridges

The Clean & Clear Plus manual sets the cleaning threshold at approximately 10 psi above the clean starting pressure. If you use a variable speed pump, the manual specifically notes that you must record the starting pressure at a consistent pump RPM — the same RPM you use each time — to get a valid comparison. Pressure readings at different RPM settings are not directly comparable.

Step 1: Open the Filter and Remove Cartridges

1. Turn off the pump at the circuit breaker or timer
2. Open the Manual Air Relief Valve — turn counterclockwise until it snaps to the full-open position
3. Wait for the pressure gauge to read zero and all pressure to fully release
4. Release the tank clamping system and lift the lid straight up — follow the filter manual's Opening the Filter procedure precisely
5. Lift out the cartridge(s) — the CCP240, CCP320, CCP420, and CCP520 all use 4 cartridges

Inspect the lid O-ring every time the filter is opened. The manual requires checking the O-ring and replacing it if it is damaged, cracked, or has flat spots. Apply a thin coat of O-ring lubricant before reinstalling. A damaged O-ring will cause air leaks or lid seal failure.

Step 2: Hose Down the Cartridges

For routine cleaning, a garden hose is sufficient to remove most debris loads:

1. Carry the cartridges away from the filter area to avoid washing debris into the equipment pad
2. Use a garden hose at moderate pressure — do not use a pressure washer, as high pressure damages cartridge pleats
3. Start at the top of each cartridge and work downward, directing the stream at a 45-degree angle into the pleats to flush debris out rather than packing it in
4. Rotate the cartridge and work around all sides
5. Rinse the center core and end caps
6. Allow to drain briefly, then reinstall
7. Reassemble, restart the pump, and record the new starting pressure

If the cartridges were loaded with standard debris (leaves, dirt, algae from a treated bloom), hosing down typically restores pressure to near the original baseline. If pressure is still elevated after hosing, proceed to a chemical soak.

Step 3: Soak in Filter Cleaner (If Hosing Alone Doesn't Restore Pressure)

Oils, sunscreen, body lotions, calcium scale, and mineral deposits embed in the cartridge fibers and cannot be removed by water pressure alone. A chemical soak breaks down these deposits.

1. Obtain a commercial cartridge filter cleaner — these are available as pre-measured tablet products designed to dissolve in a bucket of water, or as liquid concentrates; use a product specifically designed for cartridge filters
2. Follow the product label instructions for concentration and soak time — typical soaks are several hours to overnight
3. Submerge the cartridges completely in the solution
4. After soaking, rinse each cartridge thoroughly with clean water until no cleaner residue remains
5. Reinstall and record the new starting pressure

If pressure returns to near baseline after soaking, the cartridges are serviceable. If pressure is still elevated after a full soak and thorough rinsing, the cartridges have reached the end of their service life.

Step 4: Replace Cartridges

Cartridge fabric eventually becomes permanently fouled — the pleats collapse, the media becomes embedded with particles that no cleaning method can remove, or the end caps crack and allow bypass. The manual specifies that if pressure remains high after cleaning, replacement cartridges are required.

All Clean & Clear Plus models (CCP240, CCP320, CCP420, CCP520) use 4 cartridges each. Replacement P/N varies by model — consult the parts diagram in your manual or use the model number on your filter to identify the correct replacement cartridge. Replacing all 4 cartridges at the same time is recommended to ensure even flow distribution across all elements.

Replacement pressure gauge P/N: 190058. Replace the gauge if it does not return to zero when the system is off or is no longer readable.

Related Guides

• Clean & Clear Plus: Air Entering the Filter System
• Clean & Clear Plus: Short Filter Cycles
• Clean & Clear Plus: Pressure Drop on the Gauge