OpenEnergyMonitor Community

Use OpenEnergyMonitor to control a room thermostat with mbus

Hello everyone!

I have ended up on this forum because I am trying to get an mbus based room thermostat connected.

The model is a Siemens qaa70. This thermostat is connected to a hot water and heating control unit. The hot water comes from a communal boiler.

Attached is a schematic.


This will me a show of the connection.

I would like to move on to reading and controlling the switchboard. This control unit communicates with the room thermostat via MBUS.

I have seen that the shop sells a module to add MBUS via USB. Would this module allow me to communicate with my thermostat? My last resort is to integrate it into my HomeAssistant installation.

Any ideas, proposals or suggestions are welcome.

Thank you!

Hello @OrZ the mbus to usb reader is the correct hardware that you would need to read from the MBUS or/and send commands. However the software that I have written so far for use with the module is only designed for reading data from meters. You would need to work out what commands to send etc by reading through the thermostat datasheets, it might not be particularly straightforward…