Hello,
first of all I would like to thank @
EngelbertDubois for his support and answers to all those people that like me wanted to know more about the possibility to connect a Nest Thermostat E to a Bosch/Junkers boiler. On my case I have a Junkers Comfort Cerapur ZWN18-7KE23S0092, it is Heatronic 3 so I suppose that the adapter EMS to Opentherm from Nefit will do the job.
I have a thermostat Junkers FR50 which is connected to the BB ports on the Junkers Boiler. I already checked it.
When I bought my Nest Thermostat E I didn't know about this issue, therefore I ended up here and I'm glad I found this forum. I connected the heatlink to the cables available and paired it with the thermostat but it didn't work, the boiler seems to work non stop, but when the temperature is changed on the thermostat nothing happens to the boiler. It keeps only running non stop.
That's why I started to wonder if it wasn't compatible, so I found you here.
Now that I checked everything, I will order the Nefit adapter and hope for the best.
As I understood, I have to connect it to the BB ports using the black cables (there's no specific order where to put them). And the previous cables that are connected to the Thermostat from Junkers, I must connect them to the green connector from the adapter. Then I will connect the Heatlink to the end of this cable, where the old thermostat was. I don't need energy source because the Heatlink from Nest thermostat E has batteries.
After that it shout work right?
I am a bit afraid of it won't work cause I tried to connect the Heatlink before with those cables, no I don't know if I blew it up before. But I hope not because it is still connecting wirelessly with the Thermostat E.
Well, wish me good luck and thank you again for your support!
If someone thinks that it won't work, please let me know. Afraid to blew up my boiler.
Greetings from Germany,
Alex.