Pump is very noisy only when running at high speed on a variable-speed model.

Safety: Adjust settings from the control panel; no need to open equipment for this issue.

• Reduce maximum RPM: In the Zodiac pump schedule, lower the top speed and run longer at moderate speeds to achieve the same turnover.
• Improve suction conditions: Clean baskets and filters, and ensure suction valves are fully open.
• Check water level: Maintain proper pool water level to avoid drawing air.
• Listen for cavitation: A gravelly, crackling sound indicates cavitation; reducing speed usually resolves it.

Persistent cavitation can damage the impeller; adjust operation to avoid it.