Why Is My Pool Filter Pressure High?Updated a month ago

High filter pressure is a red flag that your pool’s circulation is struggling. Left unchecked, it can strain your pump, waste energy, and even damage equipment. Here’s how to diagnose and fix the issue.

Common Causes of High Pressure

1. Clogged Filter Media

   • Sand, cartridge, or DE grids are caked with debris, oils, or calcium.

   • Common in dusty areas or after storms.

2. Dirty Skimmer/Pump Baskets

   • Blockages reduce water flow, forcing the filter to work harder.

3. Algae Growth

   • Blooms clog filters rapidly (common in warm, stagnant water).

4. High Pool Usage

   • Frequent swimming or parties increase debris and organic load.

5. Closed Valves or Blocked Lines

   • Partially closed valves or stuck weir doors restrict flow.

Step-by-Step Troubleshooting

1. Check the Pressure Gauge

• Normal pressure: Note your filter’s "clean" baseline (e.g., 70–100 kPa).

• High pressure: 10–15 kPa above baseline means it’s time to act.

2. Clean Skimmer & Pump Baskets

• Turn off the pump.

• Remove leaves, twigs, or debris from baskets.

• Hose down baskets and check for cracks.

3. Backwash or Clean the Filter

• Sand/DE filters: Backwash until the sight glass runs clear.

• Cartridge filters: Remove and hose pleats, then soak in filter cleaner overnight.

• DE filters: Recharge with fresh DE powder after backwashing.

4. Check for Algae

• If water is cloudy or green, shock the pool and brush walls/floors.

• Clean the filter again post-treatment.

5. Inspect Valves & Plumbing

• Ensure all valves (e.g., skimmer, main drain) are fully open.

• Check for air leaks (hissing sounds) at pump connections.

6. Test Water Balance

• High calcium hardness (>400 ppm) or pH (>7.8) can cause scaling in filters.

• Adjust with pH decreaser or calcium reducer as needed.

Prevention Tips for Aussie Conditions

• Backwash/clean filters monthly in summer (or after dust storms/bushfires).

• Use a pool cover to reduce debris and organic load.

• Add enzyme treatments weekly to break down oils and sunscreen.

• Check pressure weekly: Catch issues before they escalate.

When to Call a Pro

• Pressure stays high after cleaning (could indicate broken laterals in sand filters).

• Suspected blockages in underground plumbing.

• Repeated algae blooms despite proper maintenance.

Need Filter Maintenance Help?

Final Tip: High pressure is your filter’s cry for help—don’t ignore it! Regular care saves energy, extends equipment life, and keeps your pool sparkling.