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Lawn Sprinkler Zone Runs Continuously: Valve Diaphragm or Solenoid Failure

One Zone Won't Shut Off When Others Run

A single zone continues running while other stations are activated, indicating a valve that fails to close.

Common Causes

Worn diaphragm: Debris, age, or tear prevents sealing.
Stuck solenoid plunger: Plunger remains up, holding valve open.

DIY Repair Guide

Visit irrigationtutorials.com for step-by-step valve rebuilding instructions. The process involves:

Shutting off water.
Removing valve bonnet.
Inspecting/replacing diaphragm.
Checking solenoid plunger movement.
Reassembling and testing.

Why It's Manageable

Valve repair requires basic tools and no electrical work. Most homeowners can complete it in under an hour per valve. Rebuild kits are inexpensive and widely available.

Irrigation: Troubleshooting a “Possessed” Zone Valve That Runs With Every Station; Troubleshooting a Sprinkler Zone That Shows Active but Delivers No Water; RC-7BI Controller Single Zone Operation: Stuck Valve Diagnosis; Orbit Valve Won't Open: Check Wiring & Timer Voltage; Front Yard Sprinkler Pressure Drop—Leak vs. Restriction Diagnosis; Front Yard Zone Shuts Off Early: Check Valve Wiring & Diaphragm; Troubleshooting a Stuck Irrigation Zone: Why Zone 19 Won't Shut Off; Starting a Lawn Genie System: Find the Main Valve and Backflow; 14 Heads on One Zone: Pressure Drop Proves Too Many Heads; Single Zone Failure in 5-Zone System: Electrical Troubleshooting

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