Need Help! Hunter PCC-900i to Rachio 3


New to the entire lawn watering scene, as I am a first time homeowner. I have this really old Hunter PCC-900i irrigation control, which cannot be upgraded to wifi, which is unacceptable for my dreams of a smart home. So I bought a Rachio 3 and I cannot figure out how to swap them, since the Hunter seems to different named ports than the Rachio. Please help me!

Even with different labeling, most are fairly easy to convert.

  1. Top-left terminal block = None of these hook to Rachio, it has its own power supply, the “remote” is your phone app, and the sensor might not be needed. I recommend first getting it working without the sensor and you can hook it up later if you decide.
    a. Gnd
    b. AC1 \ 24VAC
    c. AC2 /
    d. REM
    e. SENS
    f. SENS
  2. Bottom terminal block
    a. COM = Common for all zones
    b. P/MV = does not look like you have one, no connection
    c. 1 = zone 1, goes to same on Rachio
    d. 2 = zone 2
    e. etc.

It looks like three bundles of wires:

  1. Power
  2. Remote / Sensor
  3. Zones
  4. Maybe another bundle of zones to the right in the bottom, but they look like they come up through the right hole and go down to the left?

The only questions that I have are where some of the wires are going:

  1. It looks like the black wire from the remote/sensor bundle does to a wire nut with another black wire and I am not sure where that is going.
  2. The green wire from the remote/sensor bundle goes where? I see one green wire going to the second wire nut, but cannot quite tell where it came from nor what it is connected to.

Many controllers (not Rachio), use the sensor to “break” the COM wire. That is the thing we need to figure out.

1 Like

@Thomas_Lerman - nailed it as usual!

I think the black and green wires go to the Solar Sync device just above the controller.

The Common wire appears to be the white wire and it looks like it goes straight to the field bundle.

Thank you @DLane, not all that familiar with Solar Sync