I made it easy to install and easy to get tokens (easy to use app for Windows) to get control of your heat pump (in my case I tested Compact Belaria IR).
Check it out!
Thanks a lot for putting effort in this integration. I am desperately looking for an integration for the Hoval Connect API. However I do not have a Heatpump, but a Homevent. Is there a chance, that this integration could cover the Homevent as well? I would be opting-in as test/verification user 
I have the FR-251.
Thanks a lot for considering.
BR
Thomas