Each zone on a sprinkler system has a valve in a box in the yard, a wire back to the controller, and a shared common wire. When a zone will not start, or will not stop, the problem is somewhere in that chain.
Zone will not turn on
Check the program. Make sure the zone has a run time and is in an active program with start times.
Run it manually. Use the controller’s manual or test function.
Check for errors. Many controllers flag a shorted station and skip it.
Check the sensor. If no zones run, a rain sensor may be holding the system off, or the controller may be in rain delay.
Open the manual bleed at the valve. If the zone runs with the bleed open but not from the controller, the valve works and the problem is electrical.
Usual causes:
- A failed solenoid. We test it with a meter and replace it if needed.
- A cut wire. Fence crews, utility contractors and landscapers cut sprinkler wire often. If several zones in one area stop, suspect the common wire.
- Corroded or ant-packed splices. See fire ants in valve boxes.
- Controller damage. Lightning and surges can kill outputs.
Zone will not turn off
Stop the water first. Turn the controller off. If water keeps running, close the irrigation shut-off valve near the backflow device or meter.
If the zone stopped when you turned the controller off, it was a programming issue: an extra program or start time. If it kept running, the valve is stuck open.
Usual causes:
- Silt or debris under the diaphragm. Very common after heavy rain or a line repair.
- A torn diaphragm.
- The manual bleed left open.
- A stuck solenoid plunger.
Most of these can be fixed by cleaning or rebuilding the valve. Cracked or very old valves get replaced.
A weeping valve
A valve that closes most of the way leaks slowly to the lowest head on the zone, leaving a wet spot that never dries. That also shows up as a slowly moving meter. See high water bill.
Prevention
- Keep valve boxes clean, level and drained
- Use waterproof splices
- Flush lines after repairs before running heads
- Know where your shut-off is
Call us
Zone will not start, or will not stop? Call (346) 627-2444.
Have a question this did not answer? Call (346) 627-2444 and ask. More articles on the blog.
