How do I know if my sprinkler valve is bad?

Skip the headache, contact Sprinkler Master today!

Sprinkler systems may seem a little complicated at first. There's wires, and pipes, and they can all seem like they're tangled together like spaghetti. It's hard to make sense of it, sometimes.

When an issue comes up in your sprinkler system, it can be difficult to diagnose and find the problem. If you think you might have a problem with a sprinkler valve, we'll go over:

What and where is a sprinkler valve
How to diagnose a sprinkler valve
How to fix a valve

What is an Automatic Sprinkler Valve?

Sprinkler valves are usually found in the sprinkler manifolds in your system. These are most often found in the green boxes buried around your yard. Inside these boxes, you'll see an array of pipes and fittings with little black valves. On those black valves, you should see a cylinder rising out of the top of each valve, and wires running out of the cylinder. This black valve with the black cylinder is the electrically automated sprinkler valve. Complicated as they may seem, it's usually not hard to find -and fix- the problem.

Diagnosing the Problem:

There can be a few giveaways that a problem is almost certainly your sprinkler valve. This includes:

Sprinkler Zone not turning on consistently
Sprinkler Zone not turning off
Water leaking through sprinklers after zone is off
Sprinkler not turning on at all

If you look in the valve box, there's a few things you can look for to easily find a few problems.

Inspect the Sprinkler Valve

First, look for any leaks. If there's water in the valve box, particularly if the sprinkler zone hasn't been run in a while, this could mean either there's a crack in the sprinkler valve, or in the pipes immediately around the valves. Try turning off your main water shut-off valve for the sprinkler system, and let the box drain out. When the box is mostly drained, inspect each sprinkler valve and all the pipes. Look for cracks or punctures in all the plastics. Carefully make sure that all of the fittings are tightly secured as well, as these can loosen and leak water, causing pressure issues. While you're here, make sure the bleeder screw, pictured below, is tightened all the way.

If you haven't found any visible cracks or leaks, try turning the water back on, and going back to the box. Listen and watch for water drops. If you can see any water dripping out of a pipe, make note of where, and turn off the system again to make repairs.

Finding problems by Actuating the Valve

If you still haven't found any issues, we'll move on to actuating the valve itself. This is a good time to grab someone to help, if you haven't already.

First, take the flow control, that's the screw in the picture below (not all valves have this, so if yours doesn't, skip this step). All you're going to do is tighten this all the way clockwise, then loosen it all the way counterclockwise. Repeat this a few times. This can help work dirt and debris loose from the diaphragm inside. When you've loosened and tightened fully, loosen it all the way counterclockwise and we'll move on to the next step.

Now, put your hand on the solenoid. That's the black cylinder poking out of the top. Rotate this about a quarter turn counterclockwise. This should activate the sprinkler valve, and allow water to pass through freely. If it does, tighten the solenoid again. This should turn off the sprinkler zone again. Put your hand on the valve, and listen. If you feel or hear water trickling through the valve when the solenoid is screwed all the way in, and the bleeder screw is tightened all the way, it might be time to rebuild or replace the automatic valve.

If the sprinkler has worked perfectly through the tests thus far, it's likely an issue with a sprinkler timer or wiring. These tests should have found a problem with your automatic valve, if there was one. You can still proceed to the repair section of this article to clean the valve, but the valve itself is probably not the issue.

If you're not sure what the issue is, call Sprinkler Master. We're happy to find and fix any problem with any sprinkler system!

Repairing and Cleaning an Automatic Sprinkler Valve

Sprinkler valves are often way less complicated than people think, and they're actually quite easy to repair.

To repair a valve, we need to start with disassembly of the valve. These are pretty simple steps, but it's crucial to keep all the parts clean and organized. As you remove pieces from the sprinkler valve, clean each piece, and keep them in a clean place while you finish cleaning and reassembling the valve. Be careful to remember exactly where each piece of the valve goes.

Here are the steps to disassemble a sprinkler valve. There is a gallery of images below for reference. Clean each part with water until visibly clean and to the touch.

Remove the Sprinkler solenoid (Not necessary to clean this part, unless there is a large amount of debris on it.)
Take the screws out of the top of the housing
Carefully pry the top of the housing away
Remove the spring from the sprinkler diaphragm
Carefully remove the rubber diaphragm from the housing
Clean each part, especially the surfaces between the diaphragm and the housing
Reassemble

If any parts are damaged, you can buy most individual parts online (such as at Sprinkler Warehouse) or at your local wholesale sprinkler parts company.

Test the valve the same way as before, and hopefully your problem is fixed!