Hi everyone,
I present to you my first integration, the management of ducted air conditioning via the Koolnova system and its BMS (Building Management System) port. This is the Modbus RTU protocol over RS485 serial communication.
Koolnova provides on it website, a document describing the Modbus control registers (ref: A52102)
I had this system installed in my house and asked my installer to connect a cable to the BMS port to be able to interface it with my home automation.
Although a dev by trade, this project allowed me to get a foothold in the development of components for Home Assistant (interfacing with Home Assistant is not always easy 
)
I developed it for my needs (1 engine and 3 areas), my curiosity and my knowledge, but why not share it with others. 
Do not hesitate to give me feedback for those who wish.