Safety: No special hazards beyond normal controller adjustments.

Increase differential: In the controller settings, increase the on/off temperature differential to reduce rapid cycling.
Improve sensor placement: Ensure the pool sensor is in a stable water flow and the roof sensor is firmly attached to the Fafco panel surface.
Secure wiring: Route sensor cables away from high-voltage lines to minimize electrical interference.
Monitor operation: After adjustments, observe the system through a full heating cycle to confirm stable behavior.

Solar system intermittently turns on and off rapidly, cycling the valve and pump.

Possible Causes