Aircontrol CO2 Monitor Mini TFA

A custom home-assistant component for a family of compatible CO2 monitors distributed under various names

• TFA Dostmann CO2 Monitor AIRCO2NTROL MINI.
• ZyAura ZGm053U
• TFA Dostmann CO2 Monitor AIRCO2NTROL COACH
• ZyAura ZGm27

Idea based on "Reverse-Engineering a low-cost USB CO₂ monitor". Thx Henryk Plötz. Code for this HA integration originally taken from jansauer. Some older devices have a static encryption (as Henryk Plötz found out). This integration is both, with the newer and older devices compatible.

Setup

Upgrading from a very old version? Remove airco2ntrol from your configuration.yaml before proceeding.

Option A: HACS

1. Open HACS, search for airco2ntrol and install it
2. Restart Home Assistant
3. Go to Settings -> Integrations -> Add Integration, search for co2 and select airco2ntrol
4. Optionally enter a custom device path (e.g. /dev/airco2ntrol), or leave empty for auto-discovery
5. Once your CO2 sensor is attached, the integration will create 3 entities automatically

Option B: Manual Installation

1. Copy the custom_components/airco2ntrol folder to config/custom_components/airco2ntrol/ (Use the Samba or SSH/SFTP add-on to access your config folder)
2. Restart Home Assistant
3. Go to Settings -> Integrations -> Add Integration, search for co2 and select airco2ntrol
4. Optionally enter a custom device path (e.g. /dev/airco2ntrol), or leave empty for auto-discovery
5. Once your CO2 sensor is attached, the integration will create 3 entities automatically

Docker Setup

When running Home Assistant as Home Assistant Container, the container needs access to the USB HID device. Instead of using privileged: true, you can pass through the device directly.

Option 1: Direct device mapping

services:
  homeassistant:
    # ...
    devices:
      - /dev/hidraw0:/dev/hidraw0
    volumes:
      - /sys:/sys:ro

Note: The hidraw device number can change after a replug. See Option 2 for a stable setup.

Option 2: udev rule with stable symlink (recommended)

1. Find the Vendor/Product ID of your device on the host:

   cat /sys/class/hidraw/hidraw*/device/uevent | grep HID_ID

   This gives e.g. HID_ID=0003:000004D9:0000A052 — the last two parts are VID:PID.

2. Create a udev rule on the host:

   sudo nano /etc/udev/rules.d/99-airco2ntrol.rules

   SUBSYSTEM=="hidraw", ATTRS{idVendor}=="04d9", ATTRS{idProduct}=="a052", SYMLINK+="airco2ntrol", MODE="0666"
   

   sudo udevadm control --reload-rules
   sudo udevadm trigger

3. Update your docker-compose.yaml:

   services:
     homeassistant:
       # ...
       devices:
         - /dev/airco2ntrol:/dev/airco2ntrol
       device_cgroup_rules:
         - 'c 240:* rmw'

4. In the integration config flow, enter /dev/airco2ntrol as the device path.

This way, no privileged: true and no /sys mount are needed.

Functionality

This is how your sensors measurement might look:

This integration should provide:

• CO2 values
• Temperature
• OPTIONAL: Humidity

Some devices appear to have a humidity readings. If they do so, then the humidity entity will be usable.

Notes

The pdf in this repository describes the usb protocol used by airco2ntrol device