Irritrol 1200: Manual Start Not Working Despite Display Functioning

The controller display works (shows time), but manual zone activation fails. Slide switch to RUN, select station, set 3 minutes, press MANUAL - nothing happens. Worked this morning.

Quick Diagnostic Flow

1. Verify AC Power

Remove the 9V battery. If the display goes blank, no AC power is reaching the controller. Check transformer, outlet, GFCI, and circuit breaker.

2. Verify Water Supply

Main irrigation shutoff valve must be open. Check any master valve or backflow preventer valves.

3. Test Controller Output Voltage

With multimeter on VAC, measure between active station terminal and Common (C) while manually running that zone. Need 22-26 VAC. If absent, controller is faulty.

4. If Controller Output Is Good

Problem is in field wiring, solenoid, or valve diaphragm. Test voltage at the valve solenoid wires.

Key Insight

Since it worked this morning, check for recent changes: tripped GFCI, turned-off water valve, or physical damage to wiring from yard work.