GerlCraft Zehnder Bridge - Home Assistant integration for Zehnder ComfoAir Q
I built an ESP32-based bridge for connecting a Zehnder ComfoAir Q ventilation unit to Home Assistant via MQTT Discovery.
It exposes the relevant controls and sensors in Home Assistant, including ventilation level, operating mode, temperatures, filter status, and a dedicated 60-minute Boost switch. The bridge intentionally limits MQTT control to a defined command set.
The repository also includes:
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Ready-to-use Home Assistant dashboards, including a custom card
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A browser-based installer
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A Node-RED flow for automatic bathroom boost control
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Instructions for using a Shelly BLU H&T ZB humidity sensor with ZHA or Zigbee2MQTT
The Node-RED example enables Boost when humidity rises by at least 5 percentage points within 10 minutes, or reaches 63%. It keeps the fan boosted for at least 30 minutes and protects against repeated switching with a cooldown.
Repository and installation guide:
I would appreciate feedback, reports from other ComfoAir Q owners, and ideas for supported models or improvements.