Installation: Figuring Out the Wires?

I’ve done one previous Rachio installation, which was fairly simple and turned out great.

But, for my second installation, I’m faced with a whole bunch of spliced wires, and am finding it difficult to identify which wire is the common, and whether there is a master valve wire.

I’d appreciate anyone being able to help with this, used on this photo:

From the looks of it, you are seeing a standard analog timer, which is controlling one AC (master) water valve, which is in turn connects to an indexing valve. See more about how to set it up with rachio here (link). The only active wires appear to be Red and White, their polarity does not matter (one wire goes to common, the other to master valve port on your Rachio). In order to get a full flexibility of Rachio system, you may need to replace the indexing valve with an independent zone valves (which would require new wiring and plumbing).


Thanks very much, Gene. You’re exactly right.

We’re changing out the serial valve with individual ones today.

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Glad to be of service, good luck with the project, been there done that :slight_smile: I don’t have photo of my original timer, but it was an interesting 2 day project.

Works like a charm :wink:


Looks great! Thanks for sharing.


Thanks for the information Gene. I plan on replacing my INtermatic mechanical timer with a Rachio 2. Not sure I will individualize the zones during this part of the install. Can you share the wiring information or will that be available with the manual?

Hi Manny,

Without individualizing the zones, you will need to connect the single valve you have to the master valve (M) output of your new controller.

In order to continue using the index valve you have now, you will need to introduce a delay between zones as this allows the index valve to cycle between zones. Such a delay can be configured if your M terminal is set to the Well / Pump relay (don’t worry about nomenclature, setting your unit to this setting will not actually negatively effect your setup). Here is more info on this setting and how to gain access to the delay between zones setting.

Setting the delay between zones to about 5 minutes, should allow your index valve to cycle as needed.

Your current schedule treats all of your zones the same, unfortunately you will have to continue doing so. While the old setup seems to have watered each zone for 20 minutes twice a week, you can make some use of the flex daily schedule for added water savings (which is a big point of a smart irrigation controller). Alas you will have to set all of your zones to be clones of the thirstiest zone, meaning that when everr the controller should decide to water one of your zones, it should determine that the other three zones should be watered as well. If you want to maximize the savings, and individualize the zone settings, than you will have to individualize the vales as I’ve done in the post above.

Be sure to match all of the settings, including the sprinkler head types, slope, sun exposure, etc. You will still gain additional benefits compared to your old controller from the weather forecasts and moisture tracking.

Let us know if you run into any issues. If you notice that zones got of sync with eachother (wanting to be watered on different days), you may want to check the settings and let us know. :wink:


Great! Thanks for the detailed info. Happy Holidays!