Fermax F03430 DUOX


Has anyone managed to install the Nuki Opener with a Fermax F03430 DUOX?

I can only find threads in this forum about this model without any answer/solution, even dating back to 2020. Would be quite disappointing if Nuki has not managed to make the Opener work with this model since then.

Thanks, T.

Nuki Does not seem to be compatible with Fermax Duox Plus digital systems. Your wiring is like mine, although I have the 3450. The digital bus and the door bell. I found a work around that isn’t the best, but it is not using the Nuki opener. I knew that most all intercom systems like this has a programing feature to open the door when someone rings to your apartment. Fermax calls it “Doormatic” and it is common for doctors offices, at least in Europe… Although it was impossible to find in the programing manual how to set this feature in Duox Plus, I found it in the Fermax VDS manual. If you are interested, I can tell you how to do it or give you the link.

1 Like

Hello, I am very interested in how to connect nuki opener with fermax duox plus, they have given me model 3444. If you know how to do it, I would be very grateful if you told me.

I actually managed to get the desired functionality from using a Fermax Duox Plus Relay: DUOX PLUS RELAY | FERMAX (They also seem to have a cheaper more basic model DUOX PLUS BASIC RELAY | FERMAX that may also work, but I have not investigated that product and can only speak of the Fermax Duox Plus Relay).

The Fermax Duox Plus Relay can be programmed such that when activated and the door bell is pushed the relay will automatically releases the door (via BUS command), or open a dry contact relay.

I am using the dry contact relay to release the door lock instead of the BUS, as that gave me the best way to ensure the bell doesn’t ring and allows me to deactivate the “ring-to-open” functionality after the bell is pressed.

Activation of the Fermax Duox Plus Relay is done by a Shelly Plus 1 that activates it whenever I am close to home (using Home Assistant) with a 5 minutes timeout if the bell is never pressed. The Shelly Plus 1 is actually connected to a 2-channel relay that will both activate the Fermax Duox Plus Relay, while also cut the connection the terminal (to ensure that it does not ring the bell when the door bell is pressed). Then when the door bell is pressed the Fermax Duox Plus Relay will open the dry contact relay. This again is connected as (detached) switch to the Shelly Plus 1 and to the door lock.

The door lock will open while the Shelly Plus 1 recognized the switch input that I can use the turn off the Shelly Plus 1, which will therefore deactivate the Fermax Duox Plus Relay and also open the connection again to the terminal so that it rings the bell normally again.

If you are really interested I can provide some more details with wiring and setup.

If I am interested, can you provide me with more details about the wiring and configuration of the relay and do you know what the approximate price is?


Im also interested in this, im the owner of a 3421 duox and seems same wiring.

Could you share the wiring information?

Thanks in advance