1. Introduction
This manual provides detailed instructions for the safe and efficient use of your Deerma Ultrasonic Humidifier F628S. Please read this manual thoroughly before operating the device and retain it for future reference. This humidifier is designed to increase the humidity level in your indoor environment, contributing to a more comfortable atmosphere.
2. Important Safety Instructions
To reduce the risk of electric shock, fire, or injury, always follow these basic safety precautions:
- Always place the humidifier on a firm, flat, waterproof surface at least 12 inches (30 cm) away from walls and appliances.
- Do not place the humidifier near heat sources such as stoves, radiators, or direct sunlight.
- Do not operate the humidifier if the cord or plug is damaged.
- Unplug the humidifier before filling, cleaning, or moving it.
- Do not immerse the humidifier base in water or other liquids.
- Use only clean, cool tap water. Distilled or demineralized water is recommended to prevent mineral buildup.
- Keep out of reach of children and pets.
- Do not add essential oils or other additives directly into the water tank unless specifically designed for this model, as it may damage the unit.
3. Package Contents
Carefully unpack your humidifier and check that all items are present:
- Deerma Ultrasonic Humidifier F628S Unit
- Power Cable
- User Manual (this document)
- Odor Absorber (if included)
4. Product Overview
Familiarize yourself with the components of your Deerma F628S Humidifier.

Figure 4.1: Front View of Humidifier. This image displays the front of the Deerma F628S humidifier, featuring a sleek white design. A vertical transparent strip indicates the water level. Below this, a circular digital display shows current humidity (e.g., 55%) and other settings. Touch-sensitive buttons for power, timer, and UV function are visible around the display.

Figure 4.2: Side View of Humidifier. This image shows a side profile of the Deerma F628S humidifier, highlighting its cylindrical shape and minimalist design. The water level indicator strip is visible on the side, along with the Deerma logo.

Figure 4.3: Top View of Humidifier Lid. This image provides a close-up of the humidifier's top lid, which is a light gray circular component with a central opening for mist emission. The design is smooth and integrated, allowing for easy mist dispersal.

Figure 4.4: Internal Base of Humidifier. This image shows the internal structure of the humidifier's base when the water tank is removed. It reveals the water reservoir, the ultrasonic transducer (mist generator), and other internal components responsible for water processing and mist production. A small yellow tab is visible, likely for securing or releasing a component.
5. Setup
- Placement: Place the humidifier on a flat, stable, and waterproof surface. Ensure it is at least 12 inches (30 cm) away from walls, furniture, and electronic devices.
- Fill Water Tank: Remove the water tank from the base. Unscrew the cap at the bottom of the tank. Fill the tank with clean, cool tap water. The capacity is 5 liters. Do not fill past the MAX line. Screw the cap back on tightly.
- Replace Water Tank: Place the filled water tank back onto the humidifier base, ensuring it is seated correctly.
- Connect Power: Plug the power cable into a suitable electrical outlet. The unit will enter standby mode.
6. Operation
The Deerma F628S features touch controls for easy operation.
- Power On/Off: Touch the power icon on the display to turn the humidifier on or off. The display will illuminate when the unit is active.
- Mist Level Adjustment: Touch the mist icon (often represented by a cloud or mist symbol) to cycle through different mist output levels (e.g., Low, Medium, High).
- Timer Function: Touch the timer icon to set an operating duration (e.g., 1 hour, 2 hours, etc.). The humidifier will automatically turn off after the set time.
- UV Sterilization: If your model includes a UV function (indicated by a UV icon), touch this icon to activate or deactivate the UV sterilization feature, which helps purify the water.
- Humidity Setting: The display shows the current humidity level. Some models allow you to set a target humidity. Refer to the display icons for specific controls.
- Low Water Indicator: When the water level is low, the humidifier will automatically shut off, and an indicator light or message may appear on the display. Refill the water tank to resume operation.
7. Maintenance
Regular cleaning is essential for optimal performance and hygiene.
- Daily Maintenance: Empty and rinse the water tank and reservoir daily. Allow all parts to air dry before reassembly.
- Weekly Cleaning:
- Unplug the unit.
- Remove the water tank.
- Pour 1 cup of white vinegar into the water reservoir and let it soak for 20 minutes to loosen mineral buildup.
- Gently scrub the reservoir and ultrasonic transducer with a soft brush or cloth.
- Rinse all components thoroughly with clean water until the vinegar smell is gone.
- Wipe the exterior of the unit with a soft, damp cloth.
- Storage: If storing the humidifier for an extended period, ensure all parts are clean and completely dry. Store in a cool, dry place.
8. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No mist output | No water in tank; Unit not plugged in; Mineral buildup on transducer. | Refill water tank; Check power connection; Clean transducer as per maintenance instructions. |
| Unusual odor | Stagnant water; Dirty water tank/reservoir. | Empty and clean the water tank and reservoir thoroughly. Use fresh water. |
| Water leakage | Water tank cap not tightened; Tank not seated correctly; Unit on uneven surface. | Ensure tank cap is tight; Re-seat the water tank; Place unit on a flat, stable surface. |
| Loud noise during operation | Unit on uneven surface; Water level too low. | Place unit on a flat surface; Refill water tank. |
9. Specifications
- Model: F628S
- Brand: Deerma
- Operating Mode: Ultrasonic
- Capacity: 5 Liters
- Control Method: Touch
- Power Source: Electric Cable
- Dimensions (L x W x H): 25.4 x 5.08 x 6.86 cm (approximately 10 x 2 x 2.7 inches)
- Weight: 1.56 Kilograms (approximately 3.44 lbs)
- Recommended Room Type: Bedroom
10. Warranty and Support
For warranty information and customer support, please refer to the warranty card included with your product or visit the official Deerma website. Keep your purchase receipt as proof of purchase for any warranty claims.





