Pump runs but filter pressure is very high and flow at returns is weak

Safety first: Turn off the pump before changing valve positions or opening the filter.

• Read filter gauge: Compare current pressure to the clean starting pressure. A rise of 8–10 psi usually indicates cleaning is needed.
• Backwash or clean: Perform a full backwash (sand/DE) or remove and clean/replace cartridges.
• Check return valves: Ensure all return-side valves are open.
• Inspect heater/chlorinator: If installed, check for internal blockages per manufacturer instructions.