As SW Version 2023.6, the Bosch Thermostat integration no longer work. No connection is possible. Is there a possible solution? Is it possible to make an official Integration for this Thermostat Bosch/Buderus, I think you will make many Users happy. 
Hello,
I have the same device (TC 100.2) and I wanted to integrate it in HA but seems that with new releases it鈥檚 not longer compatible.
We are waiting for the new release that probably will come up in few weeks according with this thread: Unknown model 路 Issue #390 路 bosch-thermostat/home-assistant-bosch-custom-component 路 GitHub
Hope to get news soon!
Andrea
Hello again,
I manage to have the Thermostat working by applying a patch found here: TLS issue on init after upgrade to Homeassistant 2024.2.0 路 Issue #387 路 bosch-thermostat/home-assistant-bosch-custom-component 路 GitHub
It鈥檚 not the final solution but it鈥檚 working.
Hopes that can help you!
Andrea
Hello again,
with the new release the integration is working properly.
It is possible to close the thread.
Andrea