This is not an official app of the manufacturer. The app was tested with a Luxtronik 2. 0. Since Luxtronik Version 2. 76 the Port may be: 8889. Are you the owner of an heat pump with Luxtronik 2. 0 control? Then you can access this application on your system, read and change temperature values, and even talk to your system. Yes, you have read correctly.