Sprinkler problems happen, but usually you can fix them yourself. Today's in-ground sprinklers are designed to be easy to repair and adjust. To keep your sprinkler system working properly, keep the heads clean and free of debris. If you follow these repair tips and your sprinkler heads are still malfunctioning, it is time to consult a professional!
1. Clogged Sprinkler Heads
Clogged sprinkler heads are probably the most common problem you will run into with your underground sprinkler system. Cuttings from your lawn mower and debris from rain storms can eventually block a sprinkler head. Clogged heads are easy to identify; the spray will be interrupted, uneven, or nonexistent. Sometimes the sprinkler will just leak water which pools around the head.
The fact that sprinklers spray pressurized water out the holes doesn't mean that the sprinkler head is automatically self-cleaning. Fortunately, it's easy to clean sprinkler heads and fix this problem. You can use a piece of stiff wire (such as a paper clip) to clear the hole, but for a thoroughly dirty head, lift it from the sleeve, unscrew it, soak it, and clean with wire. Then, flush the head with running water. Make sure to turn off your irrigation system before removing the sprinkler head. Be sure to also clean out the sleeve and remove any built up grass or dirt before replacing the head.
Even if you do not notice these problems it is a good idea to clean your sprinkler heads at the start of every spring to prevent clogs.
2. Broken Sprinkler Heads
Even though many sprinkler heads are designed to pop up when the system turns on and to retract when it stops, they are often struck by mower blades or edging tools while landscaping. Fortunately, replacing a sprinkler head is easy; simply unscrew the head or stem, remove it, and screw in a replacement. Depending on your model you may need to dig down to the riser (a short vertical pipe connected to the main water pipe) and clear away the dirt before unscrewing.
Tip: If you need to buy a new sprinkler head it is a good idea to take the old head to the store with you so that you can by the exact same model.
3. Sprinklers Are Too High
When the sprinkler head sits too high above the ground, it's vulnerable to damage. This is the most common reason for broken sprinkler heads. Remedy this by lowering the heads deeper into the ground. Cut about a foot square around the head with a shovel and remove the sod or the top layer of grass and soil carefully. Then, use a hand trowel to dig carefully around the head. Move slowly and don't use too much pressure or you could cut through the water pipe. Dig deep enough that so that the top of your sprinkler heads sit only half an inch above ground level. Once you've dug deep enough and have the head lowered, carefully pack the dirt tightly back around it and replace the topsoil.
You might think it would be best to go lower than ground level to avoid lawnmower blades and other hazards, but while lower placement would probably prevent broken sprinkler heads, they would become clogged more easily with dirt and grass debris.
4. Stuck Valves
You'll know when a valve is stuck because your sprinklers will continue running after they're supposed to shut off. Home sprinkler systems often have two valves—one at each end. Most likely a chunk of debris or small rock is blocking the valve from closing and shutting off the water flow. Check both valves for this problem. Unscrew the solenoid (a cap structure, usually on the right side of the valve), let some water run through and then screw it back on. In the event that the problem isn’t solved that easily, you may need to turn off the water and use a screwdriver to remove the valve top and manually scrape out the blockage.
If you need to disassemble the valve, make sure you remember how it looks as you take it apart so you can remember how to put it back together! Each brand and model of valve is slightly different.