Yes, I noticed that too, but I don’t think it’s an issue as I found out that e.g. GitHub - arthurrump/esphome-opentherm: Create your own smart modulating thermostat using the OpenTherm component for ESPHome enables to implement it in my own way, basically.
So, for others who are interested, I plan to do this:
- buy Master OpenTherm Shield - DIYLESS Electronics - I really just need to control the boiler and don’t plan to combine it with an indoor thermostat. I am now using outside temperature to control the heating (via setting the heating curve). But extending it by an additional indoor temperature seems trivial, you have to just buy another 7$ device above (the thermostat shield)
- I will use some ESP8266 device (I prefer nodemcuv2 over Wemos as they use in the examples, but that is irrelevant, both should work just fine) to connect it with those few wires, specifically this way, and then connect the shield to the
Dconnectors on the boiler
- Then I will switch the settings on the boiler from whatever there is now to this mode 14: OpenTherm
- Will use GitHub - arthurrump/esphome-opentherm: Create your own smart modulating thermostat using the OpenTherm component for ESPHome (by tunning PID sensir) to get something like a heating curve I have now based on outside temperature sensors (which I have) and somehow tweaking it properly (I am not sure on this one)
- integrating it simply via ESPHome to home assistant and building a thermostat
It seems that it should support the two circuits: one for heating and one for domestic hot water by default. So we’ll see. If this works, it could mean that one could get rid of vicare without voiding the warranty and for under like 40$, and hopefully not that much time - it seems that I wouldn’t have to write any new code, but mainly just discover what OT interface on my does 100-W provides and then figuring out the good parameters for the heating curve/setpoint.