Ring to open doesn't work on Koch TC30

I have installed Nuki opener on my Intercom Koch TC30 and have an issue with “Ring to open” function - it doesn’t work… When I ring having “Ring to open” activated, then the ring in the apartment ring, but has a strange interruption after 1 sec and, of course, door is not opening.

Here is my connection schema:

“Open” function from the app works well and open the door.

Could you pls. help me to solve an issue.

Thanks in advance!

br, Yev.

Hi Yev
Did you get it to work? I also have a Koch TC30 and can’t get it to work. The first try with Green/Orange in A and Black in B and Original A connected with Yellow/Red doesn’t work at all, that way not even the original intercom works anymore.

The second try suggedsted by the app ( Black in A and Green/Orange in B and Original B connected with Yellow/Red) keeps the intercom working and Nuki recognizes the door bell but doesn’t open the door.

Nevermind. After a reset it works now with the second option. Don’t know why, didn’t do anything different than the first try.

What did you reset? The Opener? How? Factory settings?

Yes, the opener. I don’t remember how, but you will find instructions to reset it to factory defaults online.

Hi there, I have exactly the same issue… did try to factory reset and done the whole configuration again - same issue… I can open the door while using the app but Auto Open after Ring doesn’t to anything… In the app I receive the information about the ringing but the door doesn’t open…

What was/is your final wiring which correctly workes for you? …the one I see on the picture? Orange and Green in “a” and Blue/Black in “b”?

Hi there
I am trying to install my new Nuki opener on my Intercom Koch TC30. When I am at the last step in the App (ring the bell outside the apartment so Nuki can learn the door signal) the door doesn’t open even after the second or third attempt.
Here is how my Intercom looked before (a: white, b: blue, E: white, P: orange)

and this is what I did, see also below pic:

  • from intercom “a” to Nuki clamp 1

  • Nuki yellow and red (which looks pink…) to Nuki clamp 2

  • Nuki green and orange to intercom “a”

  • Nuki black to intercom “b” (now together with intercom blue)

Can anyone tell me what am I doing wrong?