Connected Vaillant to Home Assistant


I bought a new Vaillant ( Hr-ketel ecoTEC plus) central heating boiler a few months back, my old boiler from 2001 still worked, but I rather had it replaced, before it broke. When ordering there was an option to make it connected with the vSMART for about €200 extra. It sounded a bit to much and saw no integration with Home Assistant (HA) directly (at that time). So I tried an alternate way.


Vaillant uses a protocol called eBUS for external communication. This protocol is based on UART but at different voltage levels, so be able to use this protocol we need some hardware to do the translation. Although there were some solutions available online, I couldn’t find a tiny and SMD variant. This is why I decided to create my own PCB in KiCAD. My design is based on the following project: My project can be found here:

This PCB uses a USB to UART converter board with an CP2102, e.g this one. It is electrically isolated so no harmful ground loops or other issues can occur. There are also some helpfull LEDs to show you what is going on.

Home Assistant Integration

To integrate with Home Assistant I used ebusd running on an Raspberry Pi I had laying around. The ebusd has an MQTT client integrated, this is an easy way to hook it up to Home Assistant. To give you an idea how it is hooked up see this drawing below.

I used it in the following configuration for ebusd:

# add custom config for the vrt350 thermostat
cd /home/pi/
git clone
cd ebusd-configuration/
cp ebusd-2.1.x/en/vaillant/15.370.csv ebusd-2.1.x/en/vaillant/15.350.csv

# you can change the r; at the beginning of the lines by r1; so it will be read out automatically and pushed on MQTT

# edit /etc/default/ebusd
--configpath=/home/pi/ebusd-configuration/ebusd-2.1.x/en --mqtthost=<homeassistant_ip> --mqttport=1883 --mqttuser=<user> --mqttpass=<passwd>"

In Home Assistant I used the MQTT HVAC integration and set is up as follows:

  - platform: mqtt
    name: CV
     - auto
     - heat
     - cool
     - 'off'
    mode_state_template: >-
      {% set values = { 'auto':'auto', 'on':'heat',  'night':'cool', 'summer':'off'} %}
      {{ values[value] if value in values.keys() else 'off' }}
    mode_command_topic: "convert/modeset"
    mode_state_topic:  "ebusd/350/Hc1OPMode"
    temperature_state_topic: "ebusd/350/DisplayedHc1RoomTempDesired"
    temperature_low_state_topic: "ebusd/350/Hc1NightTemp"
    temperature_high_state_topic: "ebusd/350/Hc1DayTemp"
    temperature_low_command_topic: "ebusd/350/Hc1NightTemp/set"
    temperature_high_command_topic: "ebusd/350/Hc1DayTemp/set"
    current_temperature_topic: "ebusd/350/DisplayedRoomTemp"

Sadly my Valliant / ebusd doesn’t understand heat, cool. Also my heater can not cool (of course), but it has a night mode (low temperature setting), we use that instead. So we need to translate heat to on and cool to night, we do this with this automation:

- id: 1234
  alias: Convert HVAC Mode
  - platform: mqtt
    topic: convert/modeset
  - data_template:
      payload: '{% set mode_name = trigger.payload %} {% set modes = { ''off'':''summer'',
        ''heat'':''on'', ''cool'':''night'', ''auto'':''auto'' } %} {{ modes[mode_name]
        if mode_name in modes.keys() else ''auto'' }}'
      topic: ebusd/350/Hc1OPMode/set
    service: mqtt.publish


When having home assistant and ebusd connected we can start automating things and let the computer do stuff for us. I have configured a google calendar in which I can plan my normal heating schedule. But this only is enabled when i’m home, and turns off when I leave the house.

alias: Heater on/off on calendar
description: ''
  - entity_id: calendar.heater
    platform: state
  - entity_id: binary_sensor.people_home
    platform: state
    to: 'on'
  - condition: state
    entity_id: binary_sensor.people_home
    state: 'on'
  - condition: template
    value_template: '{{ not is_state("climate.heater", "off") }}'
  - choose:
      - conditions:
          - condition: state
            entity_id: calendar.heater
            state: 'on'
          - service: climate.set_hvac_mode
              hvac_mode: heat
            entity_id: climate.heater
      - service: climate.set_hvac_mode
          hvac_mode: cool
        entity_id: climate.heater
mode: single
alias: Heater low when nobody home
description: ''
  - entity_id: binary_sensor.people_home
    from: 'on'
    platform: state
    to: 'off'
    for: '00:05:00'
condition: []
  - data:
      hvac_mode: cool
    entity_id: climate.heater
    service: climate.set_hvac_mode
mode: single


With this integration we can control the temperature remotely or automatically. I’ve added presence detection and a google calendar so no energy is wasted which is a big plus for me. This project was fun to get my home automation kick stared and I learned something one the way. Hope this helps some of you as well!

Board available

Because of lots of requests, the boards are now availible at Tindie

35 Replies to “Connected Vaillant to Home Assistant”

  1. Hey Chris,

    I do have some PCB’s and parts, so if you want I can make one and send it to you. Do you want to solder them yourself?

  2. Hi Floris,

    nice job! I’ve just got around to connecting my Vaillant EcoTec Plus heater to Home Assistant.
    Thank you for sharing your configuration. I will definitly use parts of your configuration.

    1. Wow. Looks really nice. Possible to purchase one? 🙂 I really want to know what the f.. is going om within my heatpump, and the APP is completely rubbish!

  3. Hello Floris,

    I’m Dirk from Belgium, I am also interested in this project.
    I have a ecoVIT VKK SWE 366/4 with a actoSTOR VIH K 300 ‘Boiler’, we have a calorMATIC 430f thermostat.

    Inside of the VKK366

    I am wondering if this would work with my installation also, if this is true then I’m interested in the pcb and components, soldering is no problem.

    Alvast bedankt!

  4. Looks quite elegant indeed. Have a Brink B16HRD air heater which communicates with its thermostat using that eBUS protocol. Also got a Rarpberry Pi 3B+ with Domoticz, MQTT and Node Red running. I would like to more closely monitor that Brink air heater in order to verify its parameters ans possibly optimize those.
    So your eBUS PCB, a UART and the ebusd daemon on the Pi ought to be able to publish eBUS data to MQTT. With Node Red it would be easy to filter and channel the data towards Domoticz virtual devices for display.
    Given the 2 optocouplers this board provides bidirectional albeit simplex communication. Does it support the Wemos extension board?
    Makes me wonder if you still have such board available?
    If so please contact me. Of course some reimbursement for your costs will be in order.

    1. No the board has no Wemos support, you can probably also interface directly on a raspberry pi or some sorts, with the ebusd via other options. I will make a few boards this month, and will contact if you when it’s ready, i am waiting for a few parts.

    2. Hello Joep,

      I just read your comment. I have a Brink Allure 16 Downflow air heater as well.
      I am looking al around the internet if some has ever managed to connect with the heater via ebusd.
      I didn’t find the confidence yet to order a Ebus board and try it out myself without knowing if it will work at all.

      Can you tell me how far you are with your setup?


  5. I have integrated Vailant gas boiler from 2002 with netatmo and then did HA integration. It works perfectly. Now, I don’t care did I turn off heating as HA know when I’m at home.

  6. Hi Floris,

    I’ve build one of your PCB’s and I can confirm that the ebus part is working. But I only get device info and the date/time of the thermostat (vrt350). I have a ecoTEC VHR 30-34/5-5 heatpump. Are you using a thermostat? And how do you write to ebus? Have you changed the CSV files?

    Thanks in advance!


    1. Hey Corjan,

      I have the same thermostat, i forgot to mention that I changed the config a bit. I have used the 370 thermostat config for the 350, do not aks why but it works. so do the follwing:

      cd /home/pi/
      git clone
      cd ebusd-configuration/
      cp ebusd-2.1.x/en/vaillant/15.370.csv ebusd-2.1.x/en/vaillant/15.350.csv

      you can change the r; at the beginning of the lines by r1; so it will be read out automatically

      write is done via MQTT via the ebusd/350/Hc1OPMode/set topic

  7. Helo Floris

    Really nice job, I am looking for a Vaillant Boiler integration and your solution looks pretty good, where can I buy your PCB to get it to Spain? Could you provide it? regards.

  8. Hey Floris

    I was very excited reading what you’ve done, awesome job! I too am interested in the PCB and purchasing one if possible or if you can point me in the right direction for pets that would be greatly appreciated.

    Looking forward to integrating my boiler soon.

  9. Hey Floris,

    cool project 🙂 Is there a chance you have some leftover PCB lying around? I will be interested in buying one. Preferably with components – I can do soldering on my own.
    Please let me know.

    All the best,

  10. Hi Floris,
    Do you have PCBs to sell me or PCBs design no share?
    Pls email me, trying to connect ebus of my heating pump.

  11. Hey all, I have made an updated version of this board (can also be found on Gitlab). I’m trying to setup a small web shop but it’s not working yet. I have a few boards build and tested, please contact me if you are interested (see contact page). I sell them for €20 euro’s each and ships to Europe for €3,10.

  12. Anyone already tried to stick an ESP32 module onto this board, my older Valliant boiler from 2010 has and ebus connection but it’s to far from my home assistant setup. I’m a zero in electronics, so … anybody has an idea how this can be done?

  13. Hello, nice project, thanks for sharing! I found your article while looking at solution to connect my Vaillant boiler to my future HA install (I just moved in into a new house).

    Does this allow you to fully control your boiler (heaters & domestic hot water)? Is it as complete as the proprietary solution sold by Vaillant (vSmart or even the newer multimatic)? When you set temperature or schedule instructions into HA, does it reflect in the thermostat of your Vaillant boiler?

    If so, I would be interested in buying a “plug & play” board, do you still have some in stock? Am I correct in saying that I will just have to plug connect the ebus wires to the board, and then plug the board into a USB port of a Raspberry Pi running ebusd? What model of Raspberry Pi do you recommend?

    Thank you!

    1. Hey William, yes as far as I am aware. I can set the temperature from two places, with my Home Assistant or with the my thermostat (VRT350). Changes by HA is reflected on the display on my thermostat.

      I am using a Raspberry Pi 3, but I think lower will do as well. I have heard some people have issues with the Raspberry Pi Zero W and USB, but I haven’t tested that.

      I still have assembled and tested boards available, you can contact me directly (via contact form) or buy them via :

  14. Hello Floris,
    I recieved your adapter few days ago, connected it to my VWZ Heat pump, with Multimatic VRC 700 and MEH 61 boiler/mixer and it is working flawlessly on first try. Thank you for this awesome board.

    I just struggled a bit setting up the ebusd, the HA integration is limited so I went the MQTT route all the way.
    I am mainly using the VRC 700 circuit as it has all the info. HMU circuit is just for the current state of the heat pump and compressor modulation.

    Someone in the comment above asked if when anything is set on the termostat itself, if it is reflected in the HA/MQTT.
    I can confirm that at least with the VRC 700 this works. However when using MQTT you need to be polling the data manually for each topic. VRC 700 doesn’t automatically publish the changes, thus they are not available on MQTT.

    I set up an automation which polls these values 30 seconds from the thermostat via MQTT.
    So for example to read the current temperature set on the thermostat I use topic: “ebusd/700/z1ActualRoomTempDesired” , but for this value to be automatically updated, the topic “ebusd/700/z1ActualRoomTempDesired/get” needs to be called repeatedly to poll the value.

    These values are then used in the “climate” component in HA. Now if I set the new temp on the termostat, it takes at most 30 seconds and the correct value shows in HA.

    These are the values I am currently grabbing from ebus:

    1. Hey Jaroslav,

      Great to hear you got it working! About polling of values, you can use custom configurations see You can edit the file for your VRC 700 and change the “r” on the beginning of the line to something like “r1” so automatically poll it for you. ( ) You can probably also do this for your HMU.

      1. Thank you for the info.. yes I think I found this in the docs after I set the MQTT up, but there has been some version mismatch since the latest v21.1 (looks like the versioning scheme changed this year) and it always says there is a new version and it also complained about wrong version of config files when I downloaded them from the github (I used the ebusd-2.1.x as that’s what is in the latest folder), I guess it worked anyway but since I had to figure out how all the ebus and configurations work first I didn’t want to take a chance of having more problems.

        Now seeing this I will probably set the “r1” for the realtime values I need for the climate but I will keep the MQTT /get for other values like Energy Consumption since that needs to get updated only once a day and the config with “r9” only allows 45 seconds with poll interval of 5secs and I don’t want to clutter the bus when it’s not needed.

    2. Hello Jaroslav,
      I just got the board (Floris: thank you, you did an amazing work!) and connected it.
      I own a VRC700 too
      , could you share the yaml sections involved? climate and automation?

      Great compliments to all!


  15. Hi Floris,
    I recieved your adapter yesterday and today all works great. I have Vaillant ecoTec boiler and thermostat VRC 720. Good job.

  16. Hi Floris,
    Very interesting article and very good work! Could you please publish a BOM file. Thanks for your work!

  17. I tried buying one of your usb ebus adaptors and it said it cannot be shipped to my country (UK)…. how come?

  18. Hi Floris,

    First thanks for the initiative.
    I have also a vaillant system and I would like to be able to remotely control the heat pump setting.
    I received ebus-usb-adapter-ebuzzz-adapter. But it does not seems so easy to integrate.
    I’m a novice in Homeassistant and I failed to properly install ebusd.
    I have a raspberry 3B+.
    First which version of home assistant should I use (Home Assistant Operating System or Home Assistant Core)?
    I tried both versions, but :
    1. I don’t know how to install ebusd with Home Assistant Operating System.
    2. I tried the other method by installing Debian first in the raspberry. Then I can install ebusd, but I do not manage to start the service.
    Tanks for your help.

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