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Pump Runs But No Water: Green Wire Mystery in Valve Box

Pump activates but no water reaches any of 4 zones. All valve box wires connected except one green wire (assumed ground).

Real Issue: Pump Lost Prime

Pump running + no water anywhere = pump lost prime. Causes:

Crack in suction line
Check valve stuck open (debris, worn seat)
Screen/canister damaged

Green Wire Clarification

Irrigation "ground" (common) is a WHITE wire connected to COM/C terminal on controller and all valve solenoids. Green wire is likely equipment ground for pump/controller enclosure—not for valve operation.

Fix Sequence

Replace check valve and screen/canister
Prime pump properly
Verify pump didn't overheat from dry running
Ignore green wire—it's not the problem

Irrigation: K-Rain Timer to Rain Bird ESP: Single Black Wire Mystery Solved; Locating Buried Valve Boxes: Tips for Toro Vision Series; Hydrotek 4000 Low Pressure Daytime—K-Rain Timer Solenoid or Supply; Identifying a Backflow Preventer and Master Valve in a Sprinkler System; How Underground Sprinkler Valve Boxes Stay Securely in Place; Rewiring Hunter Pro-C Solenoid Valves: Common Wire and Zone Wiring Guide; Sprinkler Head Works Manually but Not Electrically – Bad Solenoid; Sporadic Watering: Timer Shows Run but Heads Don't Pop; Multiple Valve Problems After Contractor Relocated Three Valves; Diagnosing a Dead Zone in a 6-Zone In-Ground Sprinkler System

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