Set your preferred humidity (40%-70%) in Auto mode, and let it work unattended. Dual-Speed Modes: These dehumidifiers feature 2 fan speed modes, allowing you to flexibly choose based on your needs. Choose low-speed (L1) for quiet, energy-efficient operation in bedrooms or studies, and high-speed (L2) for quick dehumidification in heavy humid areas like bathrooms or during rainy seasons.