Replacing Hunter Pro-C w/ Rachio Gen 3

Hi All,

As a beginner to sprinkler systems, I’m taking a crack at replacing my Hunter Pro-C with a Rachio Gen 3. I’ve searched the community and can’t find a similar wiring config on a Hunter. Can anyone advise on how I should map the wires from my Hunter to my Rachio? Also, I suspect that some of the wires may be a little short to reach the horizontal layout of the Rachio. Any advice on how I can extend the wires, if necessary, is also greatly appreciated. Thanks much in advance.


@jmj89256 - should be straight forward.

  1. Ignore the yellow and green wires in the upper left quadrant (AC1, AC2 and GND), they are replaced by the Rachio transformer plut.

  2. I’m assuming the system uses a hard wired rain sensor. To be sure it would be great to know what is hooked up to the sensor ports. One of the Sens wires should go to the Rachio S1 and the other should go to the 24 VAC - port and enable the rain sensor option on Sensor 1

  3. The three wires in the COM port go to Rachio C ports. Curious as to where the grey wires run.

  4. It looks like there is a black wire going to the P/MV terminal, put that in the Rachio M terminal and select the Master Valve option in the Rachio App.

  5. For 1 through 7 on the Hunter, put those in 1 through 7 on the Rachio.

  6. Any wires that are too short, just wire nut a short piece of wire to them (AKA pig tail) - use solid wire (not stranded) and 18 gauge in size.

Good luck, have fun and welcome to the community.

Thanks for the quick reply @DLane! I mapped them as you suggested. All looks good, except that my black wire is a little too short (~1.5 inches) to reach the M terminal. Any ideas on if I can / how to extend the wire?

@jmj89256

  1. Get some solid 18 guage wire from Lowe’s or Home Depot, I know Home Depot will sell it by the foot - find sprinkler field wire with four conductors in it and buy a foot of it. Then pull out one of the wires to use.

  2. While at Home Depot/Lowe’s buy a wire nut (will probably come in a package of 4 or so). They do not need to be moisture proof.

  3. Wire nut a short (3") piece from the new wire to the existing black wire and the put the stripped end of the new wire in the M terminal.

Perfect. Thanks again!

@DLane, I attempted to follow the dirs you provided. All wires are now connected and the controller is online. When I try to run any zone, nothing happens (no watering). Any thoughts or ideas? Thanks

@jmj89256 Here are my thoughts/ideas:

  1. Was the Hunter system run to verify operation right before switching out to the Rachio?

  2. I’m curious about all the common wires, wondering where they go to.

  3. Do you have access to a multi-meter to test resitivity? If so, take the M wire, a zone wire and the common wires out. There should be low (~25-35 Ohms) resistivity down the M or zone wire and back through one of the common wires.

  4. Rain sensor isn’t active is it?

  5. The water is on to the system, correct?

Thanks @DLane!. See below

  1. Was the Hunter system run to verify operation right before switching out to the Rachio? - YES

  2. I’m curious about all the common wires, wondering where they go to. - NOT SURE EITHER

  3. Do you have access to a multi-meter to test resitivity? If so, take the M wire, a zone wire and the common wires out. There should be low (~25-35 Ohms) resistivity down the M or zone wire and back through one of the common wires. - I TESTED RESISTANCE W/ A MULTI-METER. I GOT LOW RESISTANCE WHEN I TESTED A ZONE WIRE WITH EACH COMMON WIRE. I GOT NO RESISTANCE WHEN I TESTED THE M WIRE WITH EACH COMMON WIRE. I HAVE CONFIRMED THAT I HAVE A MASTER UNIT. I HAVE CONFIRMED THAT THE UNIT M INPUT IS CONFIGURED AS THE MASTER (IN THE APP).

  4. Rain sensor isn’t active is it? - I DONT KNOW. WILL DISCONNECTING THE RAIN UNIT PREVENT THE UNIT FROM RUNNING? I CAN DISCONNECT TO TROUBLESHOOT

  5. The water is on to the system, correct? CORRECT

Disregard - I’m good. All is working. Thanks again for your help.

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