Wiring help - previous sprinkler was a rain dial

Hello - I’m working to install a new rachio 2nd gen system. I am replacing a 2007 rain dial. See page 7 and 8 of the link here to see diagram of old system:


The bottom four wires are the valve wires and I have plugged those in to the Rachio.

My question is specifically relates to the control wires and the 24 VAC wires.

There are two control wires - do I plug both of those in to the Rachio, each in a separate terminals?

There are two 24 VAC (the red and the yellow) – I realize the Rachio doesn’t need these. What do you recommend I do with these? The rain dial manual states that tthese are the connection terminals for plug-in transformer and also provides power source for CMR-KIT handheld remote (i inherited this system and I’ve never seen a remote).

Thank you

  1. You should just stick both of those control (common) wires into 1 C slot on the Rachio if you can. If not, maybe tether them together with a wire nut onto a 3rd piece of wire and have the end of that solo piece go into the C slot.

  2. You don’t need the VAC. I would recommend you trace those to the transformer and pull it out of the outlet to avoid vampire power usage.

1 Like

@DB17 - even with an eight port Rachio there are two C(ommon) ports, so another option is to put one of the white wires going to the Rain Dial VC terminal in each of the Rachio C ports. So there are three options - two wires in one port, one wire each in two ports and wire nut together with a pigtail to the port. It doesn’t matter, choose one and move on.

Welcome to the Rachio community.

1 Like

thank you both!

Sorry to come in late on this, @DLane is correct. I recommend placing each white common wire into its own C terminal to prevent these wires from getting stuck. As for the 24 V AC wires they are definitely not needed as the Rachio provides its own power adapter.

Of all the standard (not smart) controllers on the market, Irritrol Rain Dial is my all-time favorite. Maybe one day Rachio will have the beefy wiring terminals like Rain Dial. This controller is known for its lightning resistance, too.
I think you will really like Rachio. My transition was from a Toro Evolution controller.

1 Like