The instructions for the install look very straight forward, but the wires in the old Hunter control don’t seem to neatly matchup.
I see the white wires on the right side for the zones. I’m just not sure which of the white yellow blue on the left wil be required to power the new controller.
@carterbunch - The Rachio will have it’s own power. Abandon those. My guess is the big red wire will go to the C(ommon) terminal on the Rachio.
It also looks like there is a wireless rain sensor. Do you want to install that on the Rachio (not needed)?
Hi, and welcome to the club 
Looks like you will have a pretty straight forward time to switch over your old system to new.
Step 1: Connect the 5 thick white wires to terminals 1 through 5 of your new controller. Order does not really matter as you will be able to nickname the zones and take zone pictures during the setup.
Step 2: Connect the thick red wire to any of the C terminals of your new controller, to do this you will need to disconnect it from the thin white wire that it is currently connected to.
As @DLane has correctly pointed out, here are optional steps, do these only if you wish to use the rain sensor you’ve got.
Step 3: Take the thin white wire that used to connect to the thick red wire in Step 2 and twist connect it with one of the thin yellow wires (which one does not matter) that is coming out of the same black cable. You will wish for these two wires to essentially become one.
Step 4: Connect the above mentioned wire pair (white and one of the yellow) to the SC terminal (in case you have Gen 2) or 24 V- terminal (in case you have Gen 3).
Step 5: Connect the other yellow wire that you’ve not used for step 3 to SP terminal (gen 2) or 24 v+ terminal (gen 3).
Step 6: Connect the blue cable to the S1 terminal and turn on the rain sensor within the Rachio app during the setup.
Cheers,
Gene
P.S. Don’t hesitate to ask questions, and post the photos of your completed setup 
@Gene - you need to type faster or cut to the chase quicker! I gave you a head start. Your post is much more thorough and complete than mine.
@carterbunch - as Gene said, welcome to the community and you can see there are folks here that are glad to help. Enjoy your new Rachio.
@DLane - thanks for the quick response I’ll probably forgo the rain sensor as it was part of the problem with my system and prompted for the change. Also, I believe I have a remote control hooked up that I will probably keep as my sprinkler guys uses it to trigger the system when he comes to checkout it.
@Gene - thanks for all of the details. I will dig into this tonight and do my install in the morning. I will report back on my setup when completed. 
@carterbunch - the remote control won’t work with Rachio. But, you can give the sprinkler guy limited access via the Rachio app - assuming they have an iOS or Android device with them. Otherwise, they’ll have to use the buttons on the front of the unit.
@carterbunch Welcome to the community, more on sharing access of your controller.
Thanks for all of the help. It went as smooth as silk! All setup. Still have to configure the rain sensor. But I think that is attached to S1?
Well done, looks like everything should work well, your rain sensor awaits on S1 input.
Gene
You would need to locate the actual rain sensor outdoors and push a test “button” in order to activate / test the sensor. It will look something like this:
Keep in mind that, with Rachio, you do not need to have any zones running during the test (though feel free to run them if you wish). Rachio app should show a notification / display the status of the sensor. If you don’t see, via the app, your rain sensor as active during the test, you may need to check / replace the batteries in the outdoor unit.
Cheers,
Gene
Once again, thanks. Worked like a charm. Now on to the next thing testing the soil to make sure I have the smart scheduling/ durations correct.
