The AirSight Pro sensor is likely detecting interference or needs cleaning.
- Clean the sensor. Unplug the unit, place a vacuum cleaner hose over the sensor openings, and run it for at least 10 seconds.
- Avoid using an ultrasonic humidifier nearby. The mist particles can trick the sensor into reading "Bad" air quality.
- If you're using Auto Mode, switch to a manual fan speed (1-4) to bypass the sensor temporarily.
If that didn't work, and the indicator stays red after cleaning, the sensor or unit may be malfunctioning. Operating the unit in environments with humidity above 85% or temperatures outside the range of 14° to 104° Fahrenheit can affect sensor accuracy.