Gurgling or sloshing sounds from roof and intermittent flow to Heliocol panels during operation.

Safety first: Turn off pump before servicing valves or pump lid. Use caution on roof.

• Inspect vacuum relief valve: Ensure the valve closes fully when the system is pressurized. Replace if the internal mechanism is worn or stuck.
• Check pool water level: Maintain water level at mid-skimmer to prevent air from being drawn into the system.
• Seal suction leaks: Inspect and lubricate the pump lid O-ring, and tighten suction-side unions and valves to eliminate air leaks.
• Adjust pump speed: Set pump speed to a level that maintains steady flow without cavitation or excessive suction.