This plugin for Homebridge adds a temperature sensor. The temperature is the outside temperature measured by a Luxtronik2 based heat pump controller (Siemens, Novelan, Wolf, Alpha Innotec).
First follow the instructions to install Homebridge
This plugin can be installed using Homebridge Config UI X or manually by following these steps:
npm install -g homebridge-luxtronik2
Now you will have to setup your config.json for homebridge. An example is included in this repo. If you are using Homebridge Config UI X you can edit the configuration on the CONFIG tab.
A temperature sensor should appear on your iOS device as accessory in the "HOME" app.