non-cloud OpenTherm

[fictitioussherry]

I'm interested really in any non-cloud means to hook up an OpenTherm combi boiler (probably an Ideal Combi, but I'm open to suggestions) to a raspberry pi, whether z-wave or not. Somewhat mystified that nobody sells something to hook up z-wave to OpenTherm, except for very small batch production (maybe!). For me personally, my heating system seems like almost the first and last thing I want to control and monitor via a system like z-wave. But I guess I'm odd!

Has anybody managed to hook up OpenTherm to an RPi or other linux machine via ANY means that doesn't involve any "cloud", or soldering together your own board, or waiting 3 months for batch manufacturing? Where can I buy it?? Does *not* have to be z-wave, but that would be nice.

Some criteria:

* No 'cloud' involved
* Has to somehow hook up to an RPi or other linux box, by fair means or foul
* If I have to do some programming, that's not a problem
* I'd rather entirely avoid any wifi kit built into boilers (regular manufacturers are bad enough with IT security, boiler manufacturers... that's a joke, right?)
* I want to use this to (eventually): monitor air temperature, control the boiler central heating water temperature setpoint, start and stop heating, and log usage, temperatures etc. Maybe later control some TRVs, too.

Secondary question: Am I correct that the job of a device to hook up z-wave to OpenTherm is essentially to encode/encapsulate OpenTherm messages and stuff them into the z-wave mesh network? Or does it have to have some more domain-specific (i.e. heating specific) knowledge than that? If so, why?

Thanks!

[fictitioussherry]

Just to clarify: wifi that's NOT built into a boiler would be OK for me.