Don’t let a leaky valve rain on your parade
Even though they’re rarely seen (since they’re usually buried underground or tucked away in a valve box), damaged sprinkler valves have a funny way of making themselves known. When you’ve got a faulty one, you might notice that a certain part of your lawn has wet patches, low water pressure, or sprinklers that won’t turn off. If you spot any of these signs, take action quickly—otherwise, you could end up with a soggy lawn and a hefty water bill. Below, learn how to fix a sprinkler valve in six (or fewer) simple steps.
Before you start learning how to fix a leaking sprinkler valve, there’s something to keep in mind. With some sprinkler system problems, like leaks and low water pressure, the exact causes aren’t always clear. Sometimes, these issues relate to dirty or broken sprinkler valves. But in other cases, there might be something else to blame, like a cracked sprinkler line or damaged sprinkler head.
If you aren’t sure you have a valve problem, trying to fix the valve could be a waste of time. In situations like these, it’s worth hiring a local sprinkler repair professional to figure out what’s going on.
Before you begin working on your sprinkler system, make sure there’s no water or electricity flowing through it. Start by cutting off your sprinklers’ water supply at the system’s main shut-off valve.
Not familiar with your irrigation system’s shut-off valve? It’s typically a ball valve attached to a copper pipe that goes into your home at ground level and may be in a utility room, crawl space, or basement. If it’s not in any of these places, look for it outside, buried in your irrigation control valve box.
After that, shut off the power to your sprinkler system at the circuit breaker box.
Your next step is to open the valve box that houses the problematic valve. You can usually lift it from the corners, but if you have trouble opening it, look for a slot on the side to insert a screwdriver and pop the lid off.
Depending on the setup of your sprinkler system, there may be multiple valves in one valve box. Before proceeding with the next steps, make sure you know which valve is faulty. If only one valve is clearly wet or dripping into the valve box, that’ll be easy. However, identifying the right valve is a little tricker if your only clue is that the sprinklers in its zone won’t turn off or if there’s low water pressure in that zone.
To figure out which valve corresponds to that zone, you’ll first need to turn on the water and power again. Then, going valve by valve, gently twist the solenoid on each valve (which will activate its respective sprinkler zone) until you find the irrigation valve that controls the zone that won’t shut off.
With the water and power disconnected, remove the solenoid from the sprinkler valve. Usually, this just involves unscrewing it in the counterclockwise direction.
Using a soft, damp cloth or gentle brush, clear any dirt or debris from the solenoid and the opening where it sits in the valve.
In some cases, just washing off the solenoid might fix the problem. But while you’re in the valve box, it’s a good idea to clean out the sprinkler valve as well.
To do this, take off the top of the valve, either by untwisting it or removing its screws or bolts. Set these parts aside on a clean cloth. Then, continue disassembling the valve by removing the diaphragm, spring, and o-ring and placing them on the cloth as well. (It’s important to put these pieces back together in the right order, so if it helps you remember, snap a photo with your smartphone or jot down some notes with a pencil and paper.)
Take your damp cloth or brush to clean each of these parts. If anything looks particularly worn down, you may need to buy a replacement.
When all of the pieces are clean, rebuild the valve together and place it into the valve box. Next, switch on the power and slowly rotate the shut-off valve to turn on the water again.
Using your irrigation system controller, turn on the sprinklers in the faulty valve’s zone and head outside. Hopefully, your original problem—for example, a leaky valve or low water pressure—is solved. But if the issue persists, you may need to replace the solenoid.
Make sure the water and power is turned off before replacing the solenoid.
At the valve box, disconnect the wires from the top of the solenoid, taking a picture or writing down where each one goes so that you can reference it later. Remove the solenoid from the valve and set it aside. Attach the wires to the new solenoid and insert it into the valve. Put the valve back in the valve box.
Slowly turn on the water and flip on the power before testing the sprinklers again. If it still doesn’t work, it’s time to call an expert.
Intermediate DIYers can tackle certain types of sprinkler valve repairs, like switching out a solenoid or removing debris from a valve. Just be mindful to turn off your water and power each time you work on your system. Also, if you need to replace any parts (like a solenoid), make sure to buy the same brand and model as your current one.
If you’re unsuccessful with these fixes, you may need to change the sprinkler valve, which involves the steps above, plus cutting and gluing PVC pipes. It’s best to let a plumbing pro handle a full valve replacement.
For the most part, the life expectancy of a sprinkler valve is between 10 and 15 years. However, this timeline varies, depending on how much you use your sprinkler system and how well you look after it. Booking a professional irrigation system inspection once or twice per year can help you extend the life of your valves (and your overall sprinkler system). Plus, knowing how to fix a leaking sprinkler valve will help you keep your system working well between service visits.
No, you shouldn’t water your lawn every day in hot weather—or ever. For most lawns, one to three water sessions per week is sufficient. When it’s above 95 degrees Fahrenheit, watering your grass can be wasteful since the heat from the sun often evaporates the water before your lawn fully absorbs it. That’s why the best time to water grass in summer is at dawn or in the early evening (between 4 p.m. and 6 p.m.).
