DIAGNOSIS: The laser particle sensor is likely contaminated or blocked. Dust, pet hair, or cooking grease can coat the sensor lens inside the rear grille, causing inaccurate low readings.
FIX: Clean the sensor. Power off and unplug the unit. Use a can of compressed air to blow into the sensor intake slot on the back of the unit. For stubborn residue, use a cotton swab lightly dampened with isopropyl alcohol to gently wipe the slot. Let it dry completely for 15 minutes before use.
IF THAT DIDN'T WORK: Check the position. The sensor is on the back. If the unit is placed flush against a wall or in a corner, airflow to the sensor is restricted. Move the purifier at least 6 inches away from walls and furniture.
HEADS UP: Do not use Auto mode for rapid pollutant clearing from specific events like cooking. Manually select a high speed (Turbo or High). Auto mode is designed for maintaining general background air quality, not for responding to acute spikes.