Sprinkler Valve Won't Shut Off? We Have a Few Quick Fixes

Nick Durante
by Nick Durante

If your sprinkler valve will not shut off, it can become a big problem. When you cannot shut your sprinkler valve off despite your efforts, it can waste water, create a mess, and even damage the lawn.

The main causes for a sprinkler valve that won’t shut off is defective solenoids, or debris obstructing the valve. If it is a matter of debris preventing you from shutting the sprinkler valve off, cleaning is in order.

Otherwise, the valves themselves may be damaged and will need repairs or to be replaced altogether. If your defective sprinkler valve is due to a damaged or ineffective solenoid, you will need to replace it.

Follow along and see what some of the causes and remedies for a sprinkler valve that won’t shut off entail.

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Possible Causes

There are several possible causes for your sprinkler valve not shutting off, such as:

  • Damaged/defective solenoid
  • Dirt and debris obstructing the valve
  • Trapped air

More often than not, it is a case of debris causing the valve to keep running. However, damaged solenoids are a common cause of sprinkler valves not shutting off.

Less common is a lack of pressure or trapped air in the valve itself preventing the sprinkler from shutting off. Each of these possible causes for your sprinkler shutting off has a quick fix and solution.

Damaged Solenoid

A solenoid is a component in sprinkler systems responsible for opening and closing valves. Each sprinkler valve contains a solenoid and it is magnetically controlled. When a solenoid comes out of place or becomes damaged, it cannot shut off the sprinkler valve properly.

If the cause of your sprinkler valve shutting off is the solenoid, fixing it is not difficult. Follow these simple steps to fix your solenoid so your sprinkler valve will shut off:

1. Shut Off the Water

Before you can inspect and fix your solenoid, you need to shut off the water. Use your sprinkler system’s control panel to stop water from flowing into the sprinkler so that you can get to work.

2. Identify the Valve Box

The valve box lies beneath the dirt. To find the valve box, use a soil probe, such as a Bully Tools or Nupla. Gently and slowly worm the probe through the dirt until you feel the valve box.

You will hear a gentle THUD when you reach the valve box. To be safe, consider asking the professional who installed your system exactly where the valve box is beforehand.

3. Remove the Solenoid

The solenoid sits within the valve box and it looks like a tightly wrapped coil. You will notice wire nuts and small plastic screws holding the solenoid in place. Gently remove the screws and wire nuts.

Now, the only thing holding the solenoid is the screws attaching it to the top assembly. Remove those screws and pull the solenoid out of the assembly.

4. Repair or Replace the Solenoid

The solenoid may not need to be replaced entirely. If the solenoid is in good shape but is simply dirty or covered in debris, it may only need to be cleaned. That can be done gently with a little brush.

Otherwise, put in a replacement solenoid and fasten it using the same screws and nuts as in the above step. Make sure while doing this task that you keep track of each tiny component. Reclose and bury the valve box.

Turn the water supply on then try to shut it off to see if your replacement worked.

Dirt and Debris Obstructing the Valve

If your sprinkler valve won’t shut off, it is likely due to dirt and debris clogging the lines and valve. Luckily, fixing it is quite easy using the following steps:

1. Identify Which Zone is the Problem

Sprinkler systems are split into zones. You can identify which zone is the problem by turning each one on and off. The area that won’t shut off is the zone that needs to be addressed.

2. Look at the Sprinkler Heads

After identifying the problematic zone, look at the sprinkler heads within it. It should be easy to identify the heads that are clogged. They will appear dirty and covered in debris.

3. Twist the Top of the Sprinkler Head Off and Turn the Water On

Be gentle while removing the sprinkler head. You should notice immediately that there is dirt and debris beneath.

With the sprinkler head off, twist the solenoid to turn the water on. Water will spray erratically as there is no sprinkler head, but that is a good thing. The erratic flow of water will clean the dirt and debris out of the line.

4. Reattach the Sprinkler Head

When you reattach the sprinkler, the valve should be entirely rid of debris. To test it out, turn the irrigation system back on for a minute, then shut it off. Now, the sprinkler valve should shut off without any trouble.

Trapped Air

Although it is less common, trapped air can prevent your sprinkler valve from shutting off. Sprinkler system valves have water ports. Sometimes, air bubbles get caught in the water port preventing the valve from shutting off.

There is a quick fix, however, that takes no time at all. Be sure to turn on the water supply, then follow these few quick steps:

1. Manually Open and Close the Valve

Underneath the solenoid, there is usually a lever or screw at the top of the valve. Whether it is a lever or screw, you need to open it. Water should begin to leak out.

By manually opening the valve, you are allowing the air bubble to come out naturally and the valve will now shut off.

2. Use the Flow Control

If the above solution was unsuccessful, there is another option. Try using the flow control to jostle the air bubble out of the line and valve.

All that you need to do is manually turn the flow control clockwise until it is open, then, back until it is closed. Doing this should get the trapped air out of the line. It is a great, simple, and quick solution.

What to Remember

No matter which of these solutions applies to your sprinkler valve problem, remember to be careful. Irrigation systems are expensive, and you don’t want to cause damage while trying to fix the faulty sprinkler valve.

It is important to remember that if you are repairing or replacing a solenoid, you need to keep track of the parts. Each component is tiny and easy to lose track of, but you cannot put the solenoid back in place without them.

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You Can Do It Yourself

As you may have noticed, each of the above sprinkler valve fixes are easy to do by yourself. With that said, don’t feel obligated to do it without help.

If you are not confident in fixing your sprinkler valve yourself, enlist professional help. However, if it is just a matter of trapped air or dirt and debris clogging the valve, you should have no trouble fixing it alone.

In the case of replacing or repairing a solenoid, you may want to consider reaching out for help. Either way, you can fix your faulty sprinkler valve by sticking to the aforementioned solutions above. Good luck!

Nick Durante
Nick Durante

Nick Durante is a professional writer with a primary focus on home improvement. When he is not writing about home improvement or taking on projects around the house, he likes to read and create art. He is always looking towards the newest trends in home improvement.

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