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Controller Activates During Lightning Storm While in OFF Position

During a thunderstorm, a sprinkler system activates all three zones despite controller being OFF. Only shutting off main water stops it.

Immediate Reset Procedure

Remove controller backup battery
Disconnect power (unplug or turn off breaker) for 1 minute
Restore power WITHOUT battery installed
Test if issue persists

Isolating Controller vs. Valve Fault

With power OFF to controller:

Valves close: Controller was sending erroneous signals → controller defective
Valves stay open: Valves mechanically stuck open → valve issue

Lightning Damage Reality

Nearby strikes induce voltage surges that can damage controller microprocessors, causing "phantom" activation. If reset doesn't help and valves close when controller power is cut, replace the controller. Surge protection on the controller circuit is recommended for future prevention.

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