New Controller Installed, But System Still Won't Run from Timer

Symptom: Manual Valve Operation Works, Controller Doesn't

After replacing the controller, the system still won't start from the timer. Manual valve operation works fine.

Isolate: Wire or Valve

1. Run the zone from the new controller.
2. At the valve, measure voltage on the solenoid wires (22–26 VAC).
3. Voltage present: Valve is bad (solenoid or diaphragm).
4. No voltage: Field wire is damaged or disconnected.

Valve Repair

• Solenoid: unscrew, replace (match brand/model/size).
• Diaphragm: disassemble valve, replace (same match).

Wire Tracing

Use a wire toner or multimeter continuity test (with controller power OFF) to find breaks. Common failure points: valve box connections, rodent damage, shovel nicks.

Resource

irrigationtutorials.com for valve rebuild and wire tracing guides.