Diyless Thermostat 3 configuration for newbies

[viktorze]

Hi, I am trying to setup diyless thermostat 3 https://diyless.com/product/opentherm-thermostat3 but I really dont know how to proceed. I assume it is a MQTT Gateway for the first window, Opentherm gateway for the second, I dont know whether to put diyless_thermostat as a topic or diyless_thermostat/cmnd/things/thermostat/properties. I guess I am able to find the thermostat ID in properties. But what entity climate entity should I add as thermostat the Central heating or Manual?
When I try my best guess, I see some MQTT messages in channed the thermostat is not reading. Would anyone help?

[viktorze]

Sorry, now I understand that it would not work with another thermostat. I need gateway only. Sorry for the stupid question.

[sergeantd83]

In order to make the Diyless Thermostat 3 compatible with SAT, you need to flash the ESPHome firmware with the OpenTherm component.