1 out of 8 zones quit working


Hello all. I installed my Rachio Generation 2 this spring, replacing a Rain Bird ESP-M. Everything was working great until I noticed that one zone (out of 8) wasn’t watering the last 1-2 weeks. I have done a little research online, and sounds like a bad solenoid could be the problem? I opened the valve box, which houses valves for three zones, and cannot tell which is which, even after turning on each of those three zones. All I know is that 2 of the 3 zones work when I manually turn them on. The irrigation system was installed about six years ago. Any help would be appreciated. I have attached a picture of the valve box in question. I am trying to figure this out myself, as my irrigation service provider doesn’t seem interested in working with the system now that I installed the Rachio myself.


@jeff0514 - the error domain consists of:

  1. The terminal on the Rachio
  2. The wiring to the solenoid
  3. The solenoid/valve

The terminal on the Rachio can be tested by swapping a known good zone with the zone that doesn’t work. If the good zone continues to work on the non-working zone’s terminal then the terminal is good, so swap the wires back.

If one has access to a volt/ohm meter then test the resistivity between the non-working zone and C(ommon). Low resistivity means there is a circuit and the wiring is good. High or infinite resistivity could be a broken wire, broken solenoid coil or corrosion due to non-waterproof connections where the field wire is joined to the pigtail on the solenoid.

When running a zone I would think that one can feel the water running through the valve body. So running these three zones one should be able to determine which valve goes to which zone. If in doubt, after running a zone open the manual bleed valve on the zone and the water should come back on in that zone for confirmation. If the non-working valve can be manually activated by the bleed screw, then I think one is down to the solenoid or wiring - check the wire connections for both leads from the solenoid - Common and the specific field wire. Get waterproof wire nuts or connectors to repair the connections. After the pigtail from the solenoid the wires should be color coded and hopefully match was is visible at the controller.

If the non-working zone works when manually the valve’s bleed screw is manually opened and there is low resistivity on the circuit for that zone, then I’d replace the solenoid.