Why Is My Pool Filter Pressure High?
High filter pressure almost always means the filter is dirty. When the gauge reads 8 to 10 psi above your clean starting pressure, it is time to clean a cartridge filter or backwash a sand or DE filter. If pressure is still high right after cleaning, the cartridges may be clogged with oil or scale, a return valve may be partly closed, or something past the filter is blocked. In Bakersfield, dust storms and algae cleanups can load a filter in a day or two.
What causes high filter pressure?
- A dirty filter. This is the cause most of the time.
- Cartridges clogged with oils, sunscreen, or calcium scale that hosing does not remove.
- A return valve that is closed or partly closed.
- A blocked return line, a clogged return fitting, or a clogged heater or chlorinator after the filter.
- An algae bloom or a dust storm. Both fill a filter fast.
- A bad gauge. If the needle does not drop to zero when the pump is off, replace the gauge.
How do I bring the pressure down?
- Step 1: Turn the pump off and open the air relief valve before you open the filter.
- Step 2: Clean the filter. Hose off cartridges between the pleats, or backwash a sand or DE filter until the water runs clear.
- Step 3: Restart the pump, leave the air relief open until water sprays out, and write down the new clean pressure.
- Step 4: If pressure is still high, check that all return valves are fully open.
- Step 5: Soak oily or scaled cartridges in a cartridge cleaner, rinse them, and try again.
- Step 6: If cartridges are torn, flattened, or more than 2 to 3 years old, replace them.
What is a normal filter pressure?
It is different for every pool. Your normal is whatever the gauge reads right after a thorough cleaning. Write that number on the filter with a marker. Clean the filter when the gauge climbs 8 to 10 psi above it, and do not let it run far higher than that. High pressure strains the tank, the clamp, and the pump, and it cuts water flow, which lets algae get started.
When should I call for help?
Call us or come in if pressure stays high right after a good cleaning, if the gauge spikes suddenly, or if the filter tank, clamp, or valve is leaking. Never loosen a filter clamp while the pump is running. Top Dog repairs filters and installs new ones, including Sta-Rite modular media filters. If you'd rather have us come to you, a service visit starts with a $139 diagnostic fee. It covers our fuel and travel time, diagnosing your pool equipment, and a written work order for your approval. The fee doesn't cover any repairs.
How often should I clean my pool filter?
Whenever pressure rises 8 to 10 psi above its clean reading. For many Bakersfield pools that is every month or two in swim season, and more often after dust storms or algae.
What does low filter pressure mean?
The pump is not getting enough water. Check for clogged baskets, a low water level, an air leak, or a clogged impeller.
Is high filter pressure dangerous?
It can be. A filter is a pressurized tank. Always turn the pump off and open the air relief valve before you open it, and never loosen the clamp under pressure.
How often should cartridge filters be replaced?
About every 2 to 3 years, and sooner with heavy use.
Don't cry, we can help
Bring the part, a photo, or the model number to Top Dog Pool Supply, and we'll help you figure out what it needs. We repair and install pool equipment and are an authorized service center for most major brands.
Visit us at 7440 District Blvd Suite B, Bakersfield, CA 93313, or call (661) 664-9000. We're open Monday to Friday 9 to 5, Saturday 9 to 4, and Sundays 10 to 4 from April through September.
Financing is available through GreenSky: 12 monthly payments on pool equipment, interest-free when paid in full within 12 months, subject to credit approval. Call (661) 664-9000 for details.