Hi,
I’m starting my journey in Home Assistant. Installed HA and I have some smart plugs and a Nest Hub and a Nest Speaker. All good here.
I’m finishing my building my new house and had some bad guidance from Daikin Portugal stating the Nest Learning Thermostats are compatible with Daikin HVACs. So, I bought 7 Nests Learning Thermostats and when the installer was doing the install, he said “this is not compatible” 
Daikin then said they were not compatible…
So, I started my journey trying to find alternatives. It got me to find there are wifi hardware plugins that I can install in Daikin HVACs and then connect them to my Nest thermostats. This is where I got to HA. And glad I did.
My question is related to the communication of the Nests with the HVAC. I understand the Nests have auto modes that operate without human intervention that also save energy. Do the Nests send these signals as pure and simple temp up, temp down, set temp to x, etc., or is there some kind of more complex configuration that is needed?
Ultimately, can I have an installation that uses the Nests (and hopefully uses all their functionalities) and an HVAC that integrates with HA?
Thank you for the help!