When an irrigation valve breaks, it will either stick in the fully open or fully closed position, spelling disaster for your lawn. Should the valve stay open, the grass will be over-watered and mud will form and kill the grass. Should the valve remain closed, the grass in that area will die from lack of water, creating nasty brown spots in your lawn. Valves need to be fixed at the first sign of malfunction, lest your lawn suffer the consequences.
Things You'll Need
- Replacement solenoid
- Wire strippers
- Grease packed wire nuts
- Phillips screwdriver
- Replacement diaphragm
Diagnosing the valve
Locate the solenoid on the valve (a 1-inch wide plastic cylinder with two wires coming from it) and turn it to the right until tight. Locate the plastic screw sticking up from the center of the valve and turn it all the way to the right. Then make four full turns to the left. These two steps ensure that the valve is properly adjusted. If it still malfunctions, you need to move on to the other steps.
Turn the valve on with the sprinkler system's controller. Touch your fingers to the valve's solenoid. If it is not buzzing, clicking, or vibrating, the solenoid is probably bad and needs to be replaced. Turn the valve off at the controller.
Turn on the water supply to the sprinkler system (usually a valve near the system's exit point from your house or garage). Manually test the valve functionality by flipping the "on" switch for 20 seconds and then switching it "off." If the sprinkler fails to respond to either of these moves, you need to perform maintenance on the inside of the valve. Shut off the water supply to the system.
Replacing the solenoid
Unscrew the old solenoid and screw the new one in.
Cut the wires to the old solenoid with the wire strippers. Strip away 1/2-inch of insulation from these wires with the strippers. Use the gauge on the side of the strippers to determine the proper slot for stripping.
Twist one of the old wires to the already stripped wires on the new solenoid. Secure this connection by twisting a wire nut onto the end. Repeat with the last set of wires.
Performing maintainance on the inside of the valve
Remove the top of the valve by unscrewing each of the screws on its top with the Phillips screwdriver. Be careful to recover each screw as you pull it free of the valve.
Pull the top of the valve away from the bottom slowly, being sure to recover the large spring inside. Remove the diaphragm (a large rubber disc). Remove any debris sitting inside of the valve.
Inspect the diaphragm for decay, stiffness, or deterioration. Use a new diaphragm when putting the valve back together if the diaphragm is inflexible, has holes, or loses particles of rubber at your touch.
Line up the diaphragm with the screw holes on the bottom of the valve and place the spring in position on top of the diaphragm. Place the top of the valve into position above the other half of the valve and secure it into place by replacing all the screws with the screwdriver.
Tips & Warnings
- If the valve still fails to operate correctly after performing these steps, it is not broken. Rather, there is a problem with the valve's water or electronic supply. Consult a repairman or research this problem separately.
- Use a screwdriver with a magnetized tip in order to help you recover screws when you are removing them.
How to Repair a Sprinkler System Solenoid
When an irrigation system has a group of heads (a zone) that will not come on, the most common cause is a...
How to Troubleshoot a RainBird Valve
If you have a RainBird irrigation system, you may need to troubleshoot the irrigation valve from time to time. While the timer...