eBUS reader

In case it’s of interest, I’ve got a mostly baked design and schematic for an eBUS interface. It’s designed to be cheapish to manufacture by one of the common PCB manufacturing houses, and plug into a Pi Pico, or stm32f405 board. Give me a shout if anyone’s interested, and I’ll dust it off, and check the latest version into gitlab. It’s electrically isolated for USB connection, but you could just use a Pi Pico W (or other 3.3v microcontroller with bluetooth or wifi) instead.

I suggested to @glyn.hudson and @TrystanLea that an eBus reader would be a great addition to their product line. They were in the midst of the TX4 at the time, but perhaps this might be a great time to look again…

I really want one!

Definitely interested in trying an eBUS reader here, I need to setup some monitoring on a Vaillant for a friend soon and it would be interesting to explore this. @tim could I buy a board off you to try?

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Hi Trystan
How are you going to use the ebus reader to monitor the Vaillant and where will you connect it too, In the Ai unit or the heatpump itself. The ebus cable is polarity sensitive from the heatpump to the Ai unit but all the other sensors, weather comp, cylinder sensors and room stat can be connected anyway round. Really interested as Vaillant is our preferred choice and would be great to know how you are going to achieve this.

I dont really know anything about eBus yet, but keen to try it if I can. @tim how would I connect it?

@tim Do you use ebusd? GitHub - john30/ebusd: daemon for communication with eBUS heating systems

I have an ATAG boiler that allegedly has an eBUS interface.

I am not a 100% sure but I believe you can’t use both methods, it’s either ebus or traditional communications. I am not sure you would get any info from the ebus if you had a normal timer/thermostat installed. On the heatpump I would imagine you would have to intercept the signal as it went into the AI interface.


The ebus from the interface to the heatpump is dedicated so I’m assuming it’s data and signal specific.

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@modeller has used ebusd with Vaillant: c.f Vaillant Arotherm Owners Thread - #24 by modeller.
I’d certainly be interested in a OEM ebus monitor, even if my reservation for the ebus adapter 3 finally leads somewhere!

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