Aranet4 CO2 Monitor Not Connecting or Inaccurate Readings

The Aranet4 is a professional-grade CO2 monitor using Bluetooth. This guide covers connectivity and accuracy issues.

Not Connecting to App

1. Ensure Bluetooth is enabled on your phone
2. Grant location permission to Aranet app (required for BLE)
3. Press button on device to wake from sleep mode
4. Keep phone within 10 feet during connection
5. Try removing and re-pairing the device

Home Assistant Integration

1. Use Bluetooth Proxy (ESP32) for extended range
2. Add ESPHome Bluetooth proxy near Aranet4
3. Install Aranet integration from HACS
4. Enable active scanning in Bluetooth integration
5. Device updates every 2-5 minutes (configurable)

Inaccurate CO2 Readings

1. Allow 24 hours for sensor calibration after power-on
2. Place device away from windows and vents
3. Avoid breathing directly on sensor
4. Perform manual calibration outdoors (400 ppm baseline)
5. Replace device if readings never stabilize

Battery Draining Quickly

1. Increase measurement interval (1 min vs 5 min)
2. Reduce Bluetooth advertising interval
3. Use quality AA batteries (Energizer/Duracell)
4. Normal battery life is 2-4 years

Display Issues

1. E-ink display is normal to have slow refresh
2. Clean display with dry microfiber cloth
3. Avoid direct sunlight to prevent display damage
4. Display flicker indicates low battery