You may want to cap a specific sprinkler head if you have sprinkler heads that are too close together or if you want to prevent overwatering in a specific area. To cap a sprinkler head, remove the existing sprinkler cap and replace it with a flat cap that prevents water from entering the head. You can also remove the sprinkler head completely and cover it with a PVC pipe cap.
Method 1 Installing a Flat Sprinkler Cap
1. Find or buy a sprinkler cap or plug that works with your system. The flat plastic caps or plugs that fit over your sprinkler head should have come with your sprinkler system from the start. These caps obstruct the flow of water, preventing it from reaching your lawn or garden. If you can’t find the cap that came with your system, you might be able to get it from the manufacturer’s website or a hardware store.
Because each sprinkler system requires a different size cap, it’s best to find one that’s made specifically for your system.
2. Turn off the sprinkler system’s water supply. Turn off the water by finding the valve that controls the water that pumps through your sprinkler system and turning it clockwise. While you cap the sprinkler head, water will not flow out of the system.
The sprinkler system shut-off valve is usually located on the side of your house.
Sprinkler system shut-off valves are typically blue.
3. Remove the dirt from around the sprinkler head. Dig a 1–2 in (2.5–5.1 cm) hole around the sprinkler head with a gardening shovel. Set the dirt to the side so you can use it to fill the hole later.
If you clear the dirt from the top of the sprinkler head, it will not enter your system when you unscrew the head’s cap.
4. Remove the sprinkler head’s cap. To remove the cap, turn the top of the head counterclockwise. If you are unable to remove the cap, use pliers to loosen it. Continue unthreading the sprinkler head’s top until it is removed.
5. Attach the new sprinkler cap to the sprinkler head. Cover the threads on the top of your sprinkler head with the flat plastic cap made for your system. To tighten the cap, turn it clockwise.
6. Fill the hole with water and turn on the system. To reactivate the water supply valve, turn it counterclockwise. Turn on your sprinkler system and inspect the sprinkler head you capped. There should be no water coming out of it.
Method 2 Capping with PVC Pipe
1. Turn off the system’s water supply valve. Turn the sprinkler system’s water valve clockwise to turn it off and cut off water flow. This valve is usually blue and located on the side or back of your house.
When you remove the sprinkler head, the water may spray out of the system if you do not turn off the water.
2. Dig a hole 5–6 in (13–15 cm) deep around the sprinkler head. Make a hole around the sprinkler head with a gardening shovel. Set the dirt to the side so you can use it to fill the hole later.
Removing the dirt around the sprinkler head makes it easier to access and remove the sprinkler head.
3. Remove the sprinkler head. Make sure your hole is deep enough to allow you to see the sprinkler head’s base. To loosen the sprinkler head from your sprinkler system tubing, grab the long stem of the sprinkler head and turn it counterclockwise.
The extra sprinkler head can be used to replace a broken sprinkler head or in another location along your system.
4. Directly screw a PVC pipe cap onto the system. Buy a PVC pipe cap the same size as the pipe in your sprinkler system. Screw the cap onto the threads into which the sprinkler head was screwed. To secure the PVC pipe cap to the system, turn it counterclockwise.
Screwing a PVC pipe cap onto your sprinkler system will turn off that specific sprinkler head.
Typically, sprinkler systems use 1⁄2–3⁄4 in (1.3–1.9 cm) pipe.
5. Turn on the system and fill the hole with dirt. Return to the valve and turn it counterclockwise to reactivate the water supply. To turn on the sprinkler system, go to your sprinkler system controller. There should be no water coming out of the sprinkler head that you capped.
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