Need help installing Rachio 2nd gen (hunter pro c)

I need help with how to wire the rachio. the previous sprinkler system is a hunter pro c
i am confused where the AC1, AC2, and Rem go in the rachio.
i understand where the COM and P/MV and # 1-6 go.

Hi Jules,

I’m happy to help you out with this and to assure you … you’re not alone in your confusion. :relaxed:

Short answer here is all three are UNNECESSARY for our controller. This should make you life a bit easier.

  1. It appears your current (Hunter Pro-C) timer required a hard-wired power source. That’s what the AC1 & AC2 are for. It would be a good idea to cut all power to the unit - from the breaker - before disconnect. Insulate those wires in case they ever go “hot” and set aside. For our controllers, power is provided from a wall outlet and is plugged directly into the unit:

  2. The REM wire is for a remote. Also unnecessary, as you’ll be controlling your new Gen2 from our app!

Speaking of the app - since it appears you have a Master Valve (or Pump), remember to enable that setting when you configure your new controller (From the Dashboard screen > Device Settings > Advanced > Master Valve Toggle)

Happy installing, and feel free to reach out with any further questions.

~Lucas V-K


Thanks! Got it installed and running!


Dude, I came off of a pro c. Stand bye for awesomeness man, you will burn that pro c or take a bat to it.


Just for future reference in case any one else runs into this, my unit had two wires going to AC1 & AC2 (and one for REM). One set came from the power adapter and the second went outside to an external expansion/control port. I just left second/external port wires disconnected when I hooked up the Rachio.



@docBliny and @Jules – I assume that REM wire went to something that looked like this?

Note the cost of the remote control to USE the remote control port :dizzy_face:

Yes, that port was just outside on the other side of the wall.


I’m also wiring from a Hunter Pro. Just want to make sure the AC1, AC2, and Ground are not needed. Where do the two wires that were plugged into the COM on the hunter pro go to on the Rachio 2nd Gen? Also I have 2 sensor wires that were in sensor 1 and sensor 2 on the hunter pro, those are now in S1 and SC. Pics attached. Thanks for any help!

@mbaturin, correct. The Rachio controller is powered using the power adaptor included in the box. Plug into the controller following the diagram below.

These would each go into a “C” terminal. We recommend one wire per terminal.

Do you know the make/model of the sensor? I assume it’s a rain sensor? If so, you’ll need to enable the rain sensor within the app.

Hope this helps :slight_smile:

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Thanks so much - I got everything up and running yesterday. I have each of the white COM wires now going into separate C plugs on the left (1-8 zone) side. The Rain sensor wires are plugged into S1 and SC, though I don’t know which wire should go in which plug, so for now I guessed. I turned on the rain sensor in the app and went through the zone setups - all working great. Unfortunately a few of the rotor heads seem broken - i.e. water shooting out of the bottom, but that’s a separate issue that’ll be fixed by a service this weekend.

Does it matter which of the rain sensor wires go in S1 or SC? And sorry I don’t know the make/model. I’ll try to find it when I get home. It never seemed to work on my old system anyways, it would be sprinklers on during rain all the time - so I’m not too worried about it.


@mbaturin, awesome sauce! Thanks for the update.

Do you have a wired or wireless rain sensor? An easy way to see if you have the wiring test is to manually test the rain sensor.

Remember to enable Weather Intelligence on your watering schedules; it acts like a virtual rain sensor and will skip watering BEFORE it rains :wink:


Pour a cup of water into the rain sensor. Do it very slowly as some require a substrate to absorb the water. Then verify that the rain sensor is,tripped. That is what I did.


Good Idea - I will give this a shot. Is Weather Intelligence better to use than a rain sensor? Or can I use both together? How would that work if so?

i use both. rachio cant help micro climate or just bad weather data…so i found an external rain sensor to be very useful. i have an ifttt recipe to trip a 24 hour virtual rain sensor upon physcial rain sensor activation to provide rachio time to catch up to the actual percip data which readjusts my flex schedule for the following day (well 2 days out) but my rain sensor trips at .25 inch which is enough tto get my turf through 2 days.

but i like making things complicated…

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Interesting. So your rain sensor can integrate with IFTTT? What sensor do you have? How does Rachio “catch up” to the actual precip data? Does it read actuals after they happen from the weather intelligence?

the ifttt portion comes from rachio, it is an event they provide. so any rain sensor works (as long as it integrates with rachio).

Ah! I see - didnt realize that, I should explore their IFTTT triggers. Well, if I can get the sprinkler sensor working, I might just steal your idea :slight_smile: - although the PWS im using is literally down the road from me and apparently impressive as far as PWS’s go.

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Guessing this should about do it.

as emerald lugasi says, BAM!


jules, where on earth does the p/mv get plugged into? I tried a few diff ways but my sprinklers still wont turn on!