Wolf Central Heating eBus
We have a Wolf CGB-24 Gas Condensing Boiler central heating unit - with water filled radiators in each room which is very common in Europe / UK but almost unheard of in a residential setting in New Zealand.
We have had several issues with the unit as its really not supported in NZ. The main issue is air building up / getting caught in the boiler which in-turn drops the pressure below its threshold and stops the boiler from running.
This unit was new when it was installed in 2018 however it does have any 'smart' connectivity.
There is some information available on the internet however most of it is in German.
Wolf and several other Gas Central Heating manufacturers use a 2wire protocol named 'eBus'
eBus Specification: https://ebus.github.io/adapter/Spec_Prot_12_V1_3_1.pdf
Read Only Adapter: https://ebus-wiki.org/lib/exe/fetch.php/ebus/arduinoebus.pdf
Read/Write EBus Adapter v2.2: https://ebus.github.io/adapter/
Group order of parts: https://forum.fhem.de/index.php/topic,75878.0.html https://forum.fhem.de/index.php/topic,104259.120.html <-- Nov 2019