I’ve been delving into the HASS community often, doing a bit of DIY (little projects). I’ve recently decided I want to automate my heating with Homematic IP radiator thermostats but have stopped at a snag. Let me start at the beginning.
Current setup: The apartment has a gas fired boiler (radiant, 2002), which is controlled by a central thermostat in the living room (it flips the switch when the hot water starts circulating). The radiators all have dumb radiator valves / heads which open and close when needed.
Desired setup: Homematic IP thermostats on radiator valves and a way to trigger the heat demand.
While the radiator thermostats are trivial, how to start the water circulating is an entirely different matter. The old thermostat is a plain switch (no potential), combining a 24v AC current coming from and to the boiler. Basically, if I would connect the two wires, the boiler would run indefinitelly.
To make things clear, here are some basic pictures
The thermostat in the picture is connected with two 24v AC wires.
My current idea is to use the Shelly Uni, connect the two wires to the potential free. Here’s a (very) rough schematic (next post, since i’m limited):
I have tried to ask something similar on the Homematic forums, but alas, they mostly focus on the German side of the forum, so no luck. I hope that this community proves helpful.