Rachio 3 Terminal Dead

Short version: through some troubleshooting I realized one of the terminals on my Rachio 3 is dead. It’s not the end of the world because I only use 4/8 zones so I just switched to a different terminal but I was wondering if anyone ever experienced something like that and if there’s anything that can be done to get it working again?

Longer version: I noticed some plants in the yard were looking stressed so I tried to do a “quick run” on the zone and nothing happened. I tried running the zone directly from the controller, no change. I manually opened the valve and everything worked as expected (i.e., the plants got water). I noticed some water leaking at the solenoid when I manually opened the valve, so I installed a new solenoid, wired it back up and tried to “quick run” via the app and controller, but nothing worked. Manually operating the new valve functioned as expected. I finally had the bright idea to switch the wiring to a different terminal on the controller and everything worked as expected. Like I said above, it’s not the end of the world because I only use 4/8 zones but I was wondering if anyone ever experienced something like that and if there’s anything that can be done to get it working again?

You said you noticed water leaking when you manually opened the old valve. It is possible the old solenoid valve or wiring shorted out and that fried the Rachio output contact? As you said you switched to another zone terminal and it is working.

I guess that’s what I’m here to find out. Some things that lead me to believe that didn’t happen though: the leak was below the wires, the area where the wires exit the solenoid still appeared to be sealed as best I could tell, the wire nuts were the waterproof style and still had plenty of silicone, there was no signs of burning or corrosion on the terminal contact that I could see. I’ll also add that the leak was a slow drip and the zone never had a run time of more than ~15 minutes. There’s no way it would’ve been enough water leaking to do anything more than wet the ground below the valve (i.e., nothing would’ve been submerged in water in the valve box).

I guess it’s possible there was an internal fault within the solenoid that caused the terminal to fail. Unfortunately I tossed the old solenoid so I can’t go back and do any testing with it.

You are probably correct on the wiring not being shorted since the new valve worked. At another house where I lived my irrigation box with the valves used to get full of water that ran in from a nearby drip line zone. I never had an issue with a basic Hunter controller.

Yes you could have checked the old and new valve with an ohmmeter and compared the resistances. Oh well. Have you contacted Raciho customer support? They might replace it even if it is out of warranty.

At least you knew how to handle it using a spare zone.