Maico KWL: local Modbus TCP integration for Maico ventilation units, with its own dashboard card

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Hi everyone,

I own a Maico KWL (a residential ventilation unit with heat recovery) and wanted it fully in Home Assistant, locally, without the vendor app. The result is a custom integration that I have been using daily and that just reached version 0.4.0.

Dashboard

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What it does

  • Sets itself up. You enter host, port and Modbus address. The integration probes the unit, creates entities only for the registers it actually answers and detects fitted accessories (outdoor and room filter, wired and EnOcean sensors, external room sensor). You can correct the accessories in the options.
  • Read and control: temperatures of all four air streams, humidity, air quality, fan speeds, airflow, filter days, operating hours, faults and notices by name. Operating mode, ventilation level, boost, setpoints and airflow rates can be changed.
  • A fan entity that combines mode and level, so voice assistants, HomeKit and fan cards work.
  • Feed your own sensors to the unit. Room temperature, humidity or CO2 from any Home Assistant entity can be written to the unit’s bus inputs and are kept fresh automatically.
  • Values the unit does not report: heat recovery power, energy (kWh) and efficiency, dew point and absolute humidity, filter change reminders, and repair notices for faults and due filters.
  • A dashboard card is included (new in 0.4.0): the airflow through the unit with the air coloured by its temperature, so you see the heat exchange at a glance, plus room values, controls and filters. It comes with the integration, no extra resource to add.
  • Blueprints for demand boost from any sensor, reducing ventilation while a window is open, and summer night cooling.

Requirements

  • Home Assistant 2025.10 or newer
  • A Maico KWL unit reachable over Modbus TCP (available from firmware V1.1.1), directly or through a gateway. Modbus RTU (serial) is not supported yet.

Install

HACS > Custom repositories > add https://github.com/mkshb/hass-maico-kwl with category Integration, install Maico KWL, restart.

I need your help

So far the integration has been tested with one unit. If you have a Maico KWL with Modbus TCP, please try it and tell me how it went, also when everything works: Sign in to GitHub · GitHub
The form asks for the diagnostics download, which lists every register your unit answers. That is how support for other models comes about.

Repository and documentation: GitHub - mkshb/hass-maico-kwl: Home Assistant integration for Maico KWL / MVHR ventilation units over Modbus TCP. Sets itself up, runs locally, and brings its own dashboard card. · GitHub
Questions and ideas: mkshb/hass-maico-kwl · Discussions · GitHub

It is an unofficial community project, not affiliated with Maico.