I recently moved into a new home & the previous owners didn't particularly maintain it. Among the things that are in disrepair, only a fraction of the irrigation system works. The popup sprinklers in the front yard are correctly tied to the controller, but the front yard drip & back yard popup + drip sprinklers don't come on when all sprinklers are enabled from the controller.

I suspected that the sprinklers weren't properly wired to the controller because there was only one zone connected to the controller. I was able to verify this was the case for the front yard drip sprinklers because it has a manual twist knob override & the sprinklers came on when it was opened:

The left one enabled the front drip sprinklers, and the right enabled the front popup sprinklers.

In the backyard however, there is no twist knob override to manually engage the sprinklers:

I would like to manually turn them on to verify if they still work (they likely haven't been used in over 10 years) before going through the trouble of wiring them to the controller. How else can I verify that the backyard sprinklers still work?

  • If you look closely, at the back edge of the valves where the stem comes out. you can see a very small black plastic turn screw head. Just open that screw by hand or small screwdriver and the value will open. You can just barely see it in your right photo. Sep 26 '21 at 23:11

To manually open these valves, gently twist the black cylinder with the wires counter-clockwise. To close them twist them back clockwise. I have the same valves and had to look it up myself.

  • Well, all that does is determine if water pressure is present at the zone valve and it's not seized up. If you really want to make sure it's functional before wiring it to the controller, you'll want to make sure it works electrically, right?
    – DrSparks
    Sep 26 '21 at 3:05
  • @DrSparks The OP stated that he checked some valves by twisting the knob on top and asked how to check the valves without knobs. I answered his question.
    – DoxyLover
    Sep 26 '21 at 5:42
  • Thanks! It worked exactly as you described. Immediately one of the sprinklers started shooting 50 ft vertically in the air, so it seems I have some work to do :) Thankfully, other than that one and others that don't turn on, half of them still work normally
    – Drew
    Sep 28 '21 at 6:50
  • Also, where did you find the information about the valves? Online manual? If you are able to link it in the answer, that would make it even better
    – Drew
    Sep 28 '21 at 6:55

@DoxyLover is right, a half turn anticlockwise of the solenoid (black cylinder with wires) should open the valve to see if it works.

To check the solenoid itself:

Turn water off,

Cut wires and strip a little insulation off, perhaps where previously joined.

Now be ready to be careful that the moving part inside doesn't drop out.

Unscrew solenoid (don't lose the bit inside).

Cover the valve so dirt wont get in this part.

Carry the solenoid to the controller.

Touch wires to the the appropriate contacts - it will hum and click when attached to 24 v AC.

Return the solenoid to the valve soon.

Everyone, please let me know it this is correct for this exact valve (which I don't use).

For extra thoughtful people:

See if solenoid is cracked = bad.

When cutting wires see if they are green with copper rust, if so there is a higher chance of bad solenoid due to water creeping under the insulation into the solenoid.


You can get a 24 VAC power supply, typically used for older security systems, and bring it out to the zone valve with an extension cord and hook it up to the wires.

Be careful, though, 24v can give you a little tingle, so it's best not to touch the wires when it's plugged in, especially outdoors in the dirt.


Disrepair, not maintained, not all connected, no instructions. Time to spend less than $ 100 US and buy a new 6 station controller. With the new controller installed, you can activate each line separately and determine what needs repair. My 12 station system is 25 years old and no individual electric valve has failed; so chances are your valves are good . Except they could be plugged with dirt.

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