Zone Won't Turn On from Controller

Symptoms

• Zone works when you manually bleed the valve but won't activate electronically
• Controller shows the zone running but no water comes out
• Other zones work fine from the controller

Diagnosis

The 24VAC signal isn't reaching the solenoid. Causes: bad wire connection, cut wire, corroded splice, or a faulty controller terminal.

Step-by-Step Repair

1. 1

   At the controller, activate the zone. Use a multimeter set to AC voltage on the zone terminal and common (C) terminal. You should read 24-28 VAC.

2. 2

   If you get 24VAC at the controller terminals, the controller is fine. The problem is in the field wiring.

3. 3

   Go to the valve box. Disconnect the wire from the solenoid. Measure voltage at the wire ends — you should still read 24VAC.

   If no voltage at the valve, you have a wire break between the controller and the valve.
4. 4

   Check all wire splices between the controller and valve for corrosion. Re-strip, reconnect, and waterproof with grease-filled wire connectors.

5. 5

   If the wire is damaged, run a new wire from the controller to the valve.

6. 6

   Test the solenoid with a multimeter: 20-60 ohms across the coil leads is normal. Replace if open or shorted.