Rachio 3 wiring help and confirmation

Hello all,

New member here from NJ and looking for a little assistance on the wiring on my Rachio 3.
We’ve had our house for about 5 years and finally got the old Sprinkler system up and working. The piece currently installed is an Irritol Rain Dial. the wiring inside looks like this:

So I think I figured it out but was hoping someone would be able to confirm or tell me if I’m wrong.

  • I don’t need the 2 24 V on the right because those are attached to the wall plug.
  • The two S are S1 and S2, I’m thinking the top one would be considered 1 and the bottom 2, but not sure if that matters or not?
  • The issue I’m having is the white VC wire…I think that would go into the C on the Rachio 3, but not sure if that’s correct. But if it is, does it matter which C it would go into?

Any help is greatly appreciated. Thanks in advance!

@petemag - Close

  1. Correct you don’t need the 2 - 24 V lines on the right.

  2. Close - I’m guess the S wires are for a wired rain sensor. One goes in S1 and one goes in 24 V -. Not needed, but can be a backup. If it is installed, don’t forget to enable the rain sensor option in the app.

See ->

  1. Correct VC stands or Valve Common and can go in any Rachio C(ommon) terminal as all the C terminals are connected together.

  2. And it wasn’t mentioned but yellow, green, blue and orange go to a Rachio zone number e.g. 1, 2, 3, 4.


Thanks for the help! Really appreciate it.

The S is for the rain sensor, but I’m thinking it’s probably shot since it hasn’t been used in 5-6 years. I’m going to try though. I had seen the diagram in this link prior, but I was missing the first image of the rain sensor for reference. That’s why I was confused about the two S wires, since the Rachio 3 had only one going to the S.

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