Need help wiring Rachio 3 from old Hunter system

I am converting from an old Hunter system to the Rachio 3. Please see photos below of the Hunter wiring and the Rachio 3 wiring. The Rachio system boots up and connects to internet, but the zones don’t turn on. Can you please tell me what I need to change?


Rachio 3:

@blakeyoung - is the master valve option enabled in the Rachio app?

What kind of rain sensor is installed? Is the rain sensor installed in-line on the common wire?

I actually don’t have a rain sensor at the moment. Originally, with the Hunter system, there was a rain sensor, but I accidentally cut the sensor wires in the yard when digging one day. I never fixed it. I just took the rain sensor off of the fence but left the wires in the ground. I’m not sure how it is/was installed.

And yes, the Master Valve option is enabled in the app.

@blakeyoung - so I take it the Hunter system still worked with the cut rain sensor wires.

Do you have access to an ohm meter to test resistivity down the Common line and back via a zone line?

Normally white is the color associated with the Common wire. You can try putting the white wire from the Hunter RS terminal into the other Rachio C terminal (or replacing the pink wire in the left terminal).


That did it! I plugged the white wire into the other C terminal and it works great. I guess I can just leave the pink wire in the other C terminal - not sure that it’s hurting or helping anything?

@blakeyoung - my guess is the pink wire is going to the former rain sensor. I’d try the system with the pink wire disconnected and see if it still works. If the system still works, I’d leave the pink wire disconnected. The reason is that there is 24 VAC going somewhere - and if it was where the wire was cut in the yard, I’d hate for it to short against something and pull too much current through the Rachio and maybe burn out a component. Just my $0.02.

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Yellow & Pink wires where hooked up to the old rain sensor. They can be hooked up to 24V- and S1 terminals to use with Rachio

RS terminal is a rain sensor input on the old hunter controllers, if it sees voltage on that terminal, rain sensor must be tripped. Normally rain senor would short RS terminal to the C terminal and the white wire would function as if it was hooked up to the C terminal directly.

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