I have just one of my 7 sprinkler zones that seems to be at half pressure when operated with my controller. However, if I manually turn on the zone at the valve, it turns on with full pressure. Does this mean I have a bad solenoid?

  • Probably you need to replace the valve, yes.
    – Jon Custer
    Jun 29, 2022 at 18:27
  • explain the valve, the solenoid valve that gives you trouble, maybe take a picture.
    – asinine
    Jun 29, 2022 at 18:33
  • 1
    What type of valve? one with one solenoid or a manifold with seven solenoids
    – JACK
    Jun 29, 2022 at 18:34

3 Answers 3


Most likely a bad solenoid. Most sprinkler system control valves are built in such a way that repairable/replaceable parts are accessible without having to replace the entire valve. After taking it apart (with the water turned off of course), what's usually left in the ground is just a plastic form with no moving parts and nothing to wear out. That's good because it's a total PITA to swap out an entire valve. I've had to replace many solenoids in my system and an occasional diaphragm. Most of my valves are Weathermatics and are easily repaired. Take a pic of your valve and if possible, the model number and we can better help.

  • almost copy exact
    – asinine
    Jun 30, 2022 at 4:30

It would be likely one Solenoid valve is not operating properly, or just clogged.

Open the vent screw on that solenoid and let the water out (flush) for a while.

Replace the solenoid, or perform simple surgery, by opening it (with Philips screwdriver) and cleaning it, while checking that the big membrane (about 2 inches round rubber) is intact.


If it partially turns on the solenoid is probably OK something is probably obstructing the water flow. Most of those valves are pilot operated and it does not take much to partially obstruct the pilot part. I suggest you follow knowitall suggestion. You should also check the wires to be sure you have a good connection. Swapping the wires between two valves and if the problem changes it is in the wiring if not the valve is probably partially plugged. If it is the wiring be sure it is also good at the controllers end and any possible splices in the line. Do not forget to place the wiring back to its original connections.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.