Pump makes a rattling or clattering noise, especially at startup or when flow changes.

Safety first: Do not place hands near moving parts while the pump is running.

• Check suction valves and baskets: Ensure all suction valves are fully open and that skimmer and pump baskets are clean.
• Reduce pump speed: On Kripsol variable-speed pumps, reduce RPM to see if the noise diminishes. Operating at a slightly lower speed can eliminate cavitation.
• Inspect suction piping: Look for kinks, sharp bends, or undersized flexible hoses on the suction side. Replace with properly sized rigid PVC where possible.
• Re-evaluate installation height: If the pump is significantly above the pool water level, consider lowering the pump or improving suction piping to reduce lift and friction losses.

Persistent cavitation can erode the impeller and volute; address the hydraulic cause rather than ignoring the noise.