How to Connect Wires for a Sprinkler With Just One Valve

Unplug the sprinkler timer box from the AC outlet for safety while working on the electrical system.

Unfurl the sprinkler wiring, laying one end at the sprinkler timer box and the other end at the sprinkler valve box. You may need to drill a hole through an exterior wall to accommodate the wiring bundle, or you may follow the path of an existing pipe through the wall.

Separate out the white wire from the sprinkler bundle at the timer.

Push the exposed end of the white wire into the slot on the timer marked "negative" or "ground." This will be the negative connection for the circuit. Tighten the screw in the slot with a screwdriver to secure the wire.

Select a colored wire from the bunch to serve as the positive connection for the circuit. It does not matter which color you select.

Press the exposed end of the colored wire into the slot marked "zone 1" or "No. 1." This is the connection port that will control the first one on the timer. Since you are only installing a single valve, zone 1 will be the only zone your timer will control.

Twist the exposed end of the white wire at the sprinkler valve box with the white or dotted wire connected to the valve solenoid. The solenoid sits on the valve and has two exposed wires.

Twist the exposed end of the colored wire you previously selected at the timer onto the solid-colored wire connected to the solenoid.

Press each of the twisted wire bundles into grease plugs. These plugs are designed to protect the connection from water. Push the wires as deep into the caps as possible.

Plug in the sprinkler timer box and set the dial to the "run" or "test" position to test the connection. The sprinkler valve should come on within a few seconds.