Levoit Humidifier LUH-A603S Manual

The Levoit LUH-A603S is a 6L (1.59 gallon) top-fill ultrasonic cool mist humidifier designed for medium to large rooms up to 505 ft². It features a 360° nozzle, adjustable mist levels, optional night light, auto mode, sleep mode, timer (1-12 hours), and essential oil diffuser tray. It operates quietly (<38dB) and includes a built-in humidity sensor for smart humidity control. Below are key sections for safety, features, installation, setup, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Installation & Setup 3. First-Time Use 4. Specifications 5. Controls and Settings 6. Operation Modes 7. Adding Essential Oils 8. Maintenance & Cleaning 9. Safety Information 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: 6L Water Tank, 360° Rotating Nozzle, Control Panel, Essential Oil Tray, Humidistat Sensor, Power Adapter.

Feature	Description
Top-Fill Design	Easy to fill directly from the top without removing the tank
6L Large Capacity	Up to 60 hours of continuous operation on low mist setting
Ultrasonic Cool Mist	Quiet operation, safe for children and pets
360° Nozzle	Adjustable mist direction for even humidity distribution
Built-in Humidistat	Auto Mode maintains desired humidity level (40%-60% RH)
Essential Oil Tray	Separate tray for adding aromatherapy oils (not into water tank)
Adjustable Mist Levels	Three settings: Low, Medium, High
Timer Function	Set to run for 1-12 hours then auto shut-off
Sleep Mode	Display turns off, operates at lowest settings for quiet night use
Night Light	Optional warm white light with two brightness levels

Installation & Setup

Unpack and inspect all parts. Place on a flat, stable, waterproof surface away from electronics and direct sunlight.

Remove all packaging materials from inside and outside the humidifier.
Place the base unit on a level surface. Ensure the 360° nozzle is attached securely.
Fill the water tank: Remove the tank cap, fill with clean, cool tap or distilled water (max line), and replace cap.
Place the filled tank onto the base. Align properly until it sits securely.
Plug the power adapter into the DC input on the back of the unit, then plug into a 120V AC outlet.

WARNING! Do not place on carpets or uneven surfaces. Keep away from walls and furniture (minimum 12 inches clearance).

First-Time Use

Power on the humidifier; the display will illuminate.

Press the POWER button to turn on. Default mode is Manual with Medium mist.
Adjust mist output: Press MIST button to cycle through Low, Medium, High.
Set desired mode: Press MODE button to switch between Manual, Auto, and Sleep.
Set Timer (optional): Press TIMER button, then use +/- to set 1-12 hours.
Adjust night light: Press LIGHT button to cycle through Bright, Dim, Off.
For Auto Mode: The humidifier will monitor room humidity and adjust mist output to maintain 50% RH (default). Use +/- to set target humidity (40%-60%).

CAUTION! Use only clean, cool water. Do not use hot water or add oils directly to the water tank.

Specifications

Model: LUH-A603S
Water Tank Capacity: 6L / 1.59 gallons
Room Coverage: Up to 505 ft² (47 m²)
Run Time: Up to 60 hours (Low), 36 hours (Medium), 18 hours (High)
Mist Output: Up to 500 mL/hr
Noise Level: <38 dB
Power Consumption: 25W
Power Input: 120V AC, 60Hz
Humidity Control Range: 40% - 60% RH
Timer: 1-12 hours
Dimensions: 11.8" x 7.9" x 11.8"
Weight: 5.7 lbs (empty)

Controls and Settings

Control Panel: POWER, MIST, MODE, TIMER, LIGHT, +/- Buttons, Display Screen.

Display Icons: Power, Mist Level (1-3 dots), Mode (Manual/Auto/Sleep), Timer, Night Light, Humidity %, Target Humidity.

MIST Button: Cycles through Low (1 dot), Medium (2 dots), High (3 dots) mist output.

MODE Button: Manual (constant mist), Auto (smart humidity control), Sleep (display off, quiet low mist).

TIMER Button: Press to activate, then use +/- to set hours (1-12). Press again to confirm. Unit will auto shut-off after set time.

LIGHT Button: Controls night light: Bright → Dim → Off.

+/- Buttons: Adjust target humidity in Auto Mode (40%-60%). Adjust timer setting. Adjust mist output in some modes.

Operation Modes

Manual Mode: Runs continuously at selected mist level until tank is empty or turned off.

Auto Mode: Uses built-in sensor to maintain your set humidity level (default 50%). Automatically adjusts mist output. Recommended for consistent comfort.

Sleep Mode: Display turns off, mist runs at lowest setting, and noise is minimized. Ideal for nighttime use.

Timer Mode: Set 1-12 hours of operation before automatic shut-off. Combines with any other mode.

Adding Essential Oils

Use ONLY the dedicated essential oil tray. Do not add oils directly to water tank.

Ensure humidifier is off and unplugged.
Pull out the essential oil tray located near the top of the base.
Add 3-5 drops of pure essential oil onto the absorbent cotton pad inside the tray.
Slide the tray back into place securely.
Operate humidifier as normal. The mist will carry the aroma.

Tip: Replace cotton pad monthly or when aroma weakens. Clean tray regularly to prevent oil buildup.

Maintenance & Cleaning

Regular cleaning prevents mold, mineral buildup, and ensures optimal performance.

Daily: Empty and refill tank with fresh water if not used for >24 hours.

Weekly Cleaning:

Unplug unit. Remove water tank and empty any remaining water.
Clean tank with mild dish soap and warm water. Use provided cleaning brush for hard-to-reach areas.
Rinse thoroughly. Do not submerge base in water.
Wipe base exterior with a damp cloth. Clean the ultrasonic mist disc gently with a soft brush or cloth.
Air dry all parts completely before reassembly.

Descaling (Monthly or as needed):

Mix white vinegar and water (1:1) in tank. Let sit for 15-20 minutes.
Gently scrub interior with brush. Rinse multiple times until vinegar smell is gone.
For heavy deposits, use a commercial humidifier descaler following product instructions.

CAUTION! Never use abrasive cleaners, bleach, or harsh chemicals. Always unplug before cleaning.

Safety Information

Use only the provided power adapter. Do not use with damaged cord or plug.
Always place on a flat, stable, waterproof surface.
Keep out of reach of children and pets.
Do not operate without water. The unit will auto shut-off if tank is empty.
Do not cover mist outlet or block air vents.
Use only clean, cool tap or distilled water. Do not use hot water.
Do not add medications or chemicals to water.
Unplug before moving, cleaning, or when not in use for extended periods.
If abnormal operation occurs (unusual noise, smell, or no mist), stop use immediately and unplug.

Regulatory Information

FCC Compliance: This device complies with Part 15 of the FCC Rules. Operation is subject to the condition that this device does not cause harmful interference. Copyright © Levoit. All rights reserved. Levoit is a registered trademark of Vesync Co., Ltd. For support, visit www.levoit.com or contact customer service at 1-866-647-0755.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No mist output	Empty water tank / Incorrect assembly	Fill tank with water. Ensure tank is properly seated on base.
Weak mist	Mineral buildup on disc / Low mist setting	Clean mist disc (descaling). Increase mist level.
Humidifier not turning on	No power / Empty tank	Check power connection. Ensure tank has water.
Water leaking	Tank cap loose / Overfilled / Crack	Tighten cap. Do not fill above MAX line. Inspect for damage.
Unusual noise	Vibration on surface / Debris in water	Place on flat, hard surface. Use filtered or distilled water.
Display shows "EE" or "E1"	Sensor error / Water on sensor	Unplug for 10 minutes, then restart. Ensure base is dry.
Bad odor	Dirty water tank / Stagnant water	Clean tank thoroughly. Use fresh water daily.
Auto mode not maintaining humidity	Sensor blocked / Extreme room conditions	Ensure sensor area is clean. Auto mode works best in sealed rooms.

Reset: Unplug unit for 5 minutes, then restart to reset all settings to default.

Service: 1-866-647-0755; [email protected]; www.levoit.com