Extra wire going to one zone on my old controller

I’m preparing to install a new Rachio 3. My old (very old) controller has nine zones. Number 8 has two wires going to it. Why is this and should I insert both wires into the #8 Zone on the new Rachio? Could this mean #8 runs two zones, and if so, should I split them?

Thanks, Kathie

Do you know where all of your valves are? If so, I might suggest looking at the wiring for zone 8 on the other end. You can always disconnect one of the wires from the old controller, run that zone, and see what comes on. Next, repeat the process after you disconnect the other wire and reconnect the first wire. As long as you can observe what comes on (drip could be harder), you might be able to tell what is going on. If they are different valves, I probably would split them to give me better control, etc.

I know what zone runs what sprinkler heads, but nothing about the valves or wiring. I could certainly do as you suggest. If they are actually two different zones, I could create a 10th zone on the new Rachio 3. I have unplugged the old controller from electricity but can still plug it back in and try this. I have unconnected all the other wires from their respective connections and would have to be careful, I’m assuming, that they don’t touch each other. Or should I reconnect them? I will be able to see what comes on. What are the white wires for that plug into the “C” section?

Thanks, Kathie

You can just connect the two wires that went to zone 8 and all that went to common (C) since most do not know which common is for which set of valves. I would make sure the other zones’ wires do not touch anything including each other.

I was able to install and program the Rachio 3. The zone with two wires was two zones combined. I tested separated them as you suggested. Thanks so much for your help!


Glad to hear it is all working. Always glad to be of service. I presume you ended up separating the zones. Sometimes I wonder why those things happen.

I did separate the two zones that had been combined. One section watered flower beds in the back yard. The other watered flower beds around the rest of the house. We recently added two extra sprinklers in the back, so it seemed like the best thing to do.

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