DIAGNOSIS: The beep is a filter replacement reminder alarm. It activates automatically based on runtime hours, not actual air quality. The sound often occurs at night when ambient noise is low.
FIX: Silence the alarm and reset the filter timer. On the control panel, press and hold the 'Filter Reset' button for 3 seconds. You will hear a confirmation beep and the filter life indicator on the display will reset to 100%.
IF THAT DIDN'T WORK: Check if the 'Display Off' mode is active. In this mode, the screen is dark but all other functions, including beeps, remain on. The random beep could also be a Wi-Fi disconnect/reconnect alert. Ensure your Wi-Fi network is stable.
HEADS UP: Only reset the filter timer after you have installed a new, genuine Levoit replacement filter. Resetting it with an old filter will reduce cleaning efficiency and potentially damage the motor from increased strain.