Me too. Following the links, it seems it's an open source design [0] that's available as a fully populated PCB from the Netherlands for €30 [1]. The only other

Me too. Following the links, it seems it's an open source design [0] that's available as a fully populated PCB from the Netherlands for €30 [1]. The only other hardware requirement afaict is room & outdoor temperature sensors (for the Home Assistant component). But you probably have to be willing and able to wire it up yourself, or else ask around and maybe with a bit of luck find a willing plumber - I don't expect most would touch it. [0] - https://otgw.tclcode.com/schematic.html https://otgw.tclcode.com/schematic.html [1] - https://www.nodo-shop.nl/nl/48-opentherm- https://www.nodo-shop.nl/nl/48-opentherm-