My Google-Fu letting me down today, not finding what I wanted which is an open-source PCB for a wifi-enabled, multi-zone intelligent wiring centre for a home heating system. Found it before a few months back but didn't bookmark it, now I can't find it again. Anyone know of one, or better, can recommend one from personal use? All I'm getting on google is commercially available, over-priced, crap.

 

There's the Pihome project, but it's mainly about Arduino wireless sensors. However, it is possible to change the Arduino code to use RS485 instead. I feel like the Pi software is unnecessarily complex, though. Or, it may be possible to do it with some general-purpose home automation like Home Assistant and ESPHome.