Danfoss Eco Home Assistant Integration

This folder contains a custom Home Assistant integration for Danfoss Eco (eTRV) thermostats. It connects over BLE, performs the legacy key exchange flow, and exposes a climate entity plus sensors.

Credits

Original inspiration and protocol reference from Keton and AdamStrojek.

Features

• Bluetooth discovery and guided setup flow
• Key retrieval during pairing (single flow)
• Climate entity with setpoint control
• Battery, reported name, last update, and optional room temperature sensors
• Debounced setpoint writes

Install (custom integration)

1. Copy custom_components/danfoss_eco into your Home Assistant custom_components/ directory.
2. Restart Home Assistant.
3. Go to Settings → Devices & Services → Add Integration and search for Danfoss Eco.
4. Follow the setup flow, and press/hold the thermostat button when prompted.

Important: Connection Timing

The Danfoss Eco eTRV has unusually slow BLE communication:

• Initial connection: ~27 seconds
• GATT service discovery: ~30 seconds
• Total time per operation: Up to 60-90 seconds

This is normal behavior for this device. The integration uses a 90-second connection timeout to accommodate this.

ESPHome Bluetooth Proxy Limitation

ESPHome Bluetooth proxies have a hardcoded 30-second timeout for GATT operations, which is often insufficient for the Danfoss Eco. If you see errors like:

Timeout waiting for BluetoothGATTReadResponse after 30.0s

Workaround: Install patched bleak-esphome

A PR (#264) has been submitted to allow custom timeouts. Until it's merged, you can install the patched version:

# SSH into your HA instance, then:
docker exec -it homeassistant bash
pip install --upgrade git+https://github.com/jonbng/bleak-esphome.git@feat/custom-gatt-timeout
exit
ha core restart

Note: This gets overwritten on HA updates - you'll need to re-run after each update.

Alternative: Use direct Bluetooth instead of an ESPHome proxy:

1. Ensure your Home Assistant host has a working Bluetooth adapter
2. In Home Assistant, go to Settings → Devices & Services → Bluetooth
3. Make sure the device connects via the local adapter, not a proxy

Notes

• The device must be in pairing mode to retrieve the secret key (press and hold the timer button until the display shows the pairing icon).
• Reads are unlocked by writing the PIN (default 0000) to the device before polling.
• BLE access depends on your Home Assistant host Bluetooth setup.
• Due to the slow connection times, frequent polling is not recommended. The default poll interval is 1 hour.