Hi,
yes there is an API, but to access it you need to first gain a token from Grünbeck login page. With it you can access api and gain data. This is done with an SD21
If you enter this adress
https://prod-eu-gruenbeck-api.azurewebsites.net/api/devices/softliQ.D/BS… (Whereas BS… is your device ID) you get forwarded to sign up here
https://gruenbeckb2c.b2clogin.com/a50d35c1-202f-4da7-aa87-76e51a3098c6/b2c_1a_signinup/oauth2/v2.0/authorize?response_type=id_token&redirect_uri=https%3A%2F%2Fprod-eu-gruenbeck-api.azurewebsites.net%2F.auth%2Flogin%2Faad%2Fcallback&client_id=5a83cc16-ffb1-42e9-9859-9fbf07f36df8&scope=openid+profile+email&response_mode=form_post&nonce=802a5038445043b89ef9a5a0093cd037_20211129210417&state=redir%3D%2Fapi%2Fdevices%2FsoftliQ.D%2F and after signing up you get acess to api
So manually it is working to acess the API, but no idea how to automate it and bring it online in HA…
And don´t forget to vote for it 