SprinklerInstall.ca

Sprinkler zone won't turn off: causes and fixes

A zone that keeps running even with the controller off is almost always a valve problem, not a controller problem. Stop the water first, then find the cause.

Step by step

  1. 1

    Shut off the irrigation supply

    Close the irrigation shut-off valve, usually near the water meter, to stop the flow immediately.

  2. 2

    Unplug the controller

    If the zone stops when the controller loses power, the controller or its wiring is sending a signal; otherwise it's the valve.

  3. 3

    Check the valve's manual bleed

    A bleed screw or lever left open will keep a valve running. Close it hand-tight.

  4. 4

    Book a repair if it persists

    Debris under the diaphragm or a failed solenoid needs the valve opened and cleaned or replaced.

Most common causes

In order of how often we see them:

  • Grit or debris holding the diaphragm open
  • Torn diaphragm
  • Failed or loose solenoid
  • Manual bleed left open
  • Controller station stuck on (rare)

Why not to leave it

A stuck valve can run all night, flood beds, raise your water bill and wash soil out from around foundations.

Common questions

Is it the controller?
Rarely. If the zone keeps running with the controller unplugged, the valve itself is stuck open.
Can a stuck valve be cleaned instead of replaced?
Often yes — flushing debris and replacing a diaphragm is a common repair.
Book a valve repairInstant estimate

Related services

More guides

EMAILESTIMATEBOOK