Hunter Pro-C: Station 1 Runs With All Other Zones

Your Hunter Pro-C system has a master valve. Station 1 runs continuously whenever Stations 2–5 operate, but works fine alone. You've replaced a solenoid, cleaned valves, checked wiring—no fix. The issue: Station 1's valve is stuck open, and the master valve pressurizes the mainline whenever any zone runs.

Identify Which Valve Is Station 1

1. At the controller, manually run Station 6 (which has no valve connected). This pressurizes the mainline without activating a zone.
2. Go to the valve box. Listen for water flow or feel for vibration on each valve.
3. Alternatively, manually open each valve's solenoid (turn counterclockwise) to see which zone activates.
4. By elimination, identify the valve that runs when Station 6 is active—that's your Station 1 valve.

Fix the Stuck Valve

Once identified, replace both the diaphragm and solenoid on that valve. A torn diaphragm or stuck solenoid plunger causes constant seepage that becomes full flow when the master valve pressurizes the line.

Why Your Tests Didn't Work

Replacing the wrong solenoid, cleaning the wrong valve, or checking wiring won't help if the faulty valve isn't the one you serviced. The master valve setup masks the problem until you isolate the correct valve.

Follow the Station 6 pressurization method—it's the definitive way to map valves to stations on master valve systems. Good luck!