How to Repair a Sprinkler System Solenoid

When an irrigation system has a group of heads (a zone) that will not come on, the most common cause is a bad solenoid on the control valve.

While there is no way to repair the actual solenoid, it is very easy to replace the solenoid to get the zone working again. It is important to remember that the system needs to be turned off and depressurized before completing this task.

Turn the water supply off to the system, then turn the system on manually. This will depressurize the system and make it easier to change the solenoid.

Cut the control wires to the solenoid on the control wire side of the wire connections. Most irrigation systems are installed with direct bury connections attaching the control wires to the solenoid. The wires need to be cut so the connections remain on the solenoid.

Remove the solenoid from the control valve. Some valves have screws that hold the solenoid to the valve, while on others the solenoid will just unscrew. Double-check before attempting to remove.

Install the new solenoid on the valve. Make sure the solenoid is the proper solenoid for the system and valve.

Strip the control wires to expose 1/2 inch of copper wire. Twist one control wire with one solenoid wire and cap with the wire nuts from the direct bury connection. If the solenoid wires are color-coded, then match the colors with the control wires. If the solenoid wires are both the same color, then wire orientation does not matter.

Push each twisted and capped wire into the direct bury connection tube. Make sure to push all the way to the bottom. Then place one wire in each wire run at the opening and close the cap until it clicks. The wire runs are small indentations on each side of the top opening.

Things You Will Need

  • New solenoid
  • Wire cutters
  • Wire strippers
  • Direct bury connections or some other waterproof connection

Tip

  • Ask your local home improvement professional for DBY connectors. These are direct bury connectors that fit most home irrigation wiring.

Warnings

  • Make sure the solenoid is the proper solenoid for the system and valve.
  • Any questions about this process need to be directed to a local irrigation professional.

About the Author

Michael Rippetoe has been writing for 15 years, and has recently decided to make it his career. He has been a journeyman carpenter, ASE Master Mechanic, certified irrigation professional and currently writes for this site, designs websites, and does professional photography. Rippetoe's articles appear on eHow, Garden Guides, AnswerBag and others.