My Yard Sprinklers Are Leaking at the Valve

Identifying the Leak

• Turning on the sprinklers will cause water to flow into each valve one by one as the zones rotate. Watching the irrigation box as the valves cycle will show you which valves have a leak. Allow the system to cycle through each of the zones to identify where the leaks are located. A leak can be located at the base of the valve, the top of the valve or along the pipe near the valve. Watch where water is flowing from to identify the exact location of the leak.

Causes of Leaks

• Because sprinkler valves are located on plastic pipes, they are susceptible to cracks and breakage due to freezing. Water that is allowed to freeze inside a sprinkler manifold will expand. This expansion will crack plastic or create enough pressure on the base of the valve to break the seal between the valve and the manifold supply line. Water pressure in excess of 70 psi can also lead to broken valve connections. High water pressure can occur as water surges in your system or while charging a sprinkler line for the first time.

Repairing Leaks

• Leaking sprinkler valves that are cracked should be replaced with a new unit. Old valves can be removed by twisting the body of the valve counterclockwise until it pulls free from the manifold pipe. Place a new valve on the manifold and screw clockwise into place. If a crack is located under a valve on the manifold pipe, the crack must be sealed using a chemical pipe wrap. The pipe wrap contains an adhesive that seals the crack as it dries, allowing you to repair the manifold under the valve without removing the valve or replacing the manifold itself.

Sealing Sprinkler Valves

• Some sprinkler valve leaks can be fixed using nothing more than Teflon tape. In cases where water is dripping gently from the connection point between the valve and the manifold pipe, remove the valve by turning it counterclockwise. Wrap the pipe threads on the base of the valve with a layer of Teflon plumber's tape, and re-tighten the valve into the hole on the manifold. The tape will lubricate the threads and create a watertight seal in the connection. This method is effective on very minor leaks.