Pump runs but is unusually loud with a rattling or cavitation sound; bubbles visible under pump lid.

Safety first: Turn off power before adjusting valves or opening the pump.

• Raise water level: Ensure the pool water level is high enough to prevent vortexing at the skimmer.
• Open suction valves fully: Make sure all suction valves are fully open to reduce restriction.
• Reduce pump speed: On variable-speed AquaFlo pumps, lower the RPM to a level that still provides adequate circulation but reduces noise and cavitation.
• Check for air leaks: Inspect and tighten suction unions, lubricate the lid O-ring, and verify that any suction-side check valves are not drawing air.