Humidifier or dehumidifier shows F2 and stops; may occur in very cold or hot rooms.

Steps:

• Check room conditions: Verify the room temperature is within the operating range specified in the manual (commonly 5–35°C). Move the unit if necessary.
• Inspect ambient sensor: Unplug the unit, remove the front grille, and locate the ambient sensor near the air inlet. Ensure it is not touching hot components or trapped behind insulation.
• Reseat and test: Reseat the sensor connector on the PCB. If F2 persists in a normal-temperature room, test and replace the ambient temperature sensor (NTC) as needed.