Rain sensor always activated

I have a Rachio 3, 12-zone. I installed a Rainbird WR2 over the weekend. Rainbird appears to be functioning (there doesn’t seem to be a way to test it manually, but the temperature reading appears correct, all displays functioning, etc.) But whenever I enable S1 on the Rachio it goes into ‘Rain sensor on’ mode and skips all schedules. I left it on for a couple days and the setting never cleared. There was no rain that occurred during this time and the temperature stayed above the setting on the Rainbird. The display on the Rainbird shows that the controller should be in ‘normal irrigation operations’ and not blocked.

Here is a photo of my wiring

Any thoughts on what the problem could be?

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Taking Green into S2 did not help, same thing. The ‘rain sensor on’ state was always on.

Dual function “rain” sensors appear the same to Rachio, no matter if they are tripped by rain or temperature. Is your outdoor temperature below the set point for the freeze protection?

Nope. Outdoor temps were in the low 60s and Rachio was still in ‘rain sensor on’ mode

Is this sensor wired for normally open or normally closed?

I’m not sure. There is no option for wiring the sensor itself, they are hardwire within the body of the sensor.

There needs to be the white wire from receiver connected to S2 jn order for the circuit to not register open and sensor operate properly.

Have you seen these articles re: the WR2? https://support.rachio.com/hc/en-us/articles/115010541788-Rachio-compatibility-with-RAIN-BIRD-WR2-Wireless-Rain-Sensor

According to the Rainbird Specifications “ The sensor shall be wired to normally closed (N.C.) controllers – in series with the valve com- mon, or alternately, wires shall be inserted into the appropriate controller sensor terminal ports.“
Since the Rachio instructions say “ * Sensor ( S1 , S2 ) terminals - use S1 or S2 for a single sensor, NOT both

  • Sensor common ( 24 VAC - ) terminal. This corresponds to the SC terminal on the Generation 2
  • Sensor power ( 24 VAC + ) terminal - for wireless (powered) rain sensors . This corresponds to the SP terminal on the Generation 2.”

I believe you should move the white wire from 24v- to SP2 as it appears that the white wire is the rain sensor wire and should be connected to a sensor terminal not the common terminal.

I’ve sent my Rainbird WR2 unit back because I do think it was faulty (it wouldn’t trigger the rain sensor on it’s own controller even after dousing the sensor.) Hopefully the replacement unit will “just work”. I’m still not convinced there isn’t something wrong with my Rachio sensor terminals, but testing it with a replacement Rainbird will give more insight.

I have a Rachio 3 – which by the documentation linked above, I have wired the WR2 to the Rachio correctly.

Final followup. It turned out my original Rainbird WR2 was bad. After getting a replacement unit and following the Rachio Gen 3 wiring guide, everything is working as it should be.