Rainbird ESP-TM to Rachio 3

I am coming from a Rainbird ESP-TM (6 zone I think?) and the previous home owner left this disconnected for us with 2 sets of wires. I bought the Rachio 3 thinking it was going to be easy to figure out, but none of my zones are watering during the test.

I bundled both white wires to one C slot and then plugged all of the the other colors into each zone slot. Left the yellow wire untouched as I thought that was a “jumper” that is not necessary.

I don’t believe I am running a rain sensor, but could be wrong. I know very little about irrigation wiring.

Why would there be 2 sets of identical wires? How would I wire this?


Have you found all the sprinkler boxes and valves? Do you know how many zones? Two sets of wires could mean two irrigation boxes. Do you happen to have a multimeter (using it to measure ohms can help to find the common)? Which state are you in (just ask since some seem to use indexed valves and others standard valves)?

I don’t know where the sprinkler box/valves are. I don’t know how many zones.

I do have a multimeter.

I’m in California.

@androofoo - Here we go:

  1. I don’t think you have an indexing system based on all the wires. Normally indexing systems just have one wire/zone running to the controller (plus the common).

  2. Two sets of wires could be - one for the front yard, one for the back yard or had 6 (or more zones) and didn’t want to buy 8 or 10 conductor wire, so they used the existing wire for a few runs. Could be one common wire or two.

  3. Start with the white wire in each bundle and see if there is continuity to each of the other wires in that bundle. If one white wire doesn’t have any continuity with the wires in it’s bundle, then test for continuity with the other white wire to the wires in that bundle. If some wires don’t have continuity and the others do, then they may not be connected to a valve - be sure to label them.

  4. Start looking around your property for round or rectangular boxes in the ground with a green cover. Irrigation valves are many times placed in these. Also, look for a backflow prevention device or cut off valve that can cut off water to the sprinkler system.

Report back your findings and we’ll see if we can come up with a plan. We need to make sure the water is on to the system, so that is why you need to find the backflow preventer and/or valves.

@DLane thank you for the quick response.

  1. The house came with artificial grass in the backyard and I checked for any extra irrigation systems - could not find any.

  2. How do I do a continuity test for my situation? I saw this YouTube video, but he had some wires hooked up already.

  3. I spent the last hour trying to find a rectangular box but couldn’t find anything. Looked at my main water line and found 2 valves. Not sure exactly what these are but they are both opened. I have a DIG irrigation system, but it looks to be independent of the sprinkler system.


As @DLane said (I was thinking unlikely too, but wanted to double check), it is unlikely you have indexed valves. White as you chose is the probably the most commonly used for common, but not always. I might even just do one bundle of wires first and ignore the other for now. Using the multimeter, if you check for continuity or resistance, you can double check whether that is the common or not. If continuity or resistance (20 - 60 ohms) across two wires will tell you one is common and the other is a valve. So, if white is one of those wires, you can check to see if it seems to be connected to more than one valve. Remember that it is possible one or more wires might not be connected to anything. If white does not seem to be common, then try another wire. If you do find a common wire, you can try methodically testing the wire in the bundle. Once you find what seems to the the common, you can try it one Rachio, but still might not get water.

Do you know if you have irrigation water separate from your culinary water? If you do not know, you should be able to call the water utilities company. I was born & raised in the Sacramento area and never personally had separate water. We also never had a worry about freezing, so we always had the irrigation water on. We never had an above ground backflow preventer like some places that I have seen. I realize that none of this is necessarily the same for you. The concern is, is there a valve or anything that has the water turned off? This is why it might be necessary to find boxes and valves (main could be outside a box too). Do you have the ability to ask the previous owners any of these questions?

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I don’t have direct contact with the previous owners, but I can ask my real estate agent to see if he can reach out. Only been a home owner for 2 years. Can wrench the hell out of a car, but this irrigation thing is the hardest thing ever.

Thanks for the help. I’m gonna try the multimeter test. So the wires don’t have to be connected to the Rachio, right? Example, I put it in Continuity mode, black on white wire, red on other colored wires. I should be seeing 20-60 ohms?

I could be wrong, but the picture looks like it could be the water main on the right with the vertical valve turning off the water to the house and the horizontal to the PVC for the valves to the left. Those look like battery powered DIG drip valves that you mentioned, is that correct?

Depending on the multimeter, continuity may be separate from the resistance. Here is an image:

Usually resistance will display Ohms and continuity beeps and displays 1 (if I remember correctly)