Home Automation Domotica Forum Europe, Bwired Forum

Hi, let me explain my situation:

• Home Assistant on rPi4
• Vaillant combi heater (2010, don't remember the name) with OpenTherm PCB installed
• Floorheating on the first floor/living room (brand WARP Systems)
• Basic Honeywell modulating room thermostat
• 1st and 2nd floor radiators (and I have zigbee thermostats ready).

Currently the heater only looks at the living room temperature, but I want to be able to have multiple zones, so I can heat my home office (on the 2nd) and my wife's office (on the 1st) separately.

So, how do I set this up? I am able to write software (I control everything through appdaemon right now).
Do I need to? Thanks for any pointers.

Ron

I suggest to start simple. First just put the OTGW between the thermostat and boiler. Then use OTmonitor to look at the messages being exchanged. Make sure you see different messages from the thermostat and that it is getting responses from the boiler.

Find yourself a copy of the opentherm protocol specification on the internet, if you don't already have it. Use it along with the messages being exchanged between the thermostat and boiler to make sense of how the thermostat controls the boiler. You can also try some serial commands to figure out which do and which don't work with your system.

Once you have a feel for the system, you can introduce Home Assistant and/or create your own control of the heating based on the heating demands in other rooms.