Honeywell Humidifier HWM-340B Manual

The Honeywell HWM-340B is a cool mist humidifier designed to add moisture to dry air, helping to relieve dry skin, nasal congestion, and other discomforts caused by low humidity. It features a 1-gallon tank capacity, adjustable mist control, automatic shut-off, a night light, and a wicking filter. 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 7. Maintenance & Cleaning 8. Filter Replacement 9. Safety Information 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: Water Tank, Base Unit with Mist Nozzle, Control Panel, Wick Filter, and Power Adapter.

Feature	Description
1-Gallon Tank	Removable tank for easy filling
Adjustable Mist Control	Dial to control mist output (Low/High)
Automatic Shut-Off	Turns off when tank is empty or removed
Night Light	Soft blue light for nighttime use (on/off switch)
Wick Filter	Traps minerals and impurities from water
360° Mist Nozzle	Adjustable direction for optimal mist distribution
Easy-Fill Design	Wide opening for convenient refilling
Quiet Operation	Designed for bedroom or office use
Filter Change Indicator	Light alerts when filter needs replacement
Carry Handle	Integrated handle for easy portability

Installation & Setup

Unpack and inspect all parts. Place on a flat, stable, level surface away from walls and electronics.

Remove the water tank from the base.
Install the wick filter: Remove from packaging, soak in cool water for 15 minutes, then insert into the filter slot in the base.
Fill the tank: Turn tank upside down, remove cap, fill with cool, clean water (do not exceed max fill line). Replace cap securely.
Place tank back onto base, ensuring it is seated properly.
Plug the power adapter into the base unit and then into a standard 120V AC outlet.

WARNING! Use only clean, cool water. Do not use hot water or add essential oils, as this may damage the unit. Keep away from children.

First-Time Use

After installation, power on the humidifier.

Press the Power button. The unit will beep and the display will light up.
Adjust the mist output using the Mist Control dial. Start on Low for initial use.
Turn the Night Light on or off using the dedicated button, if desired.
Allow the unit to run for a few minutes; mist should be visible from the nozzle.
Adjust the 360° mist nozzle to direct moisture away from walls and furniture.

CAUTION! Place the humidifier on a water-resistant surface. Do not place on carpets or delicate surfaces.

Specifications

Model: HWM-340B
Tank Capacity: 1 Gallon (3.8 Liters)
Room Coverage: Up to 250 sq. ft.
Run Time: Up to 24 hours on Low setting
Mist Output: Adjustable, up to 1.5 gallons per day
Power: 120V AC, 60Hz, 25W
Filter Type: Demineralization Wick Filter (Part # HWMF-340)
Dimensions (LxWxH): 10.2" x 10.2" x 13.8"
Weight (Empty): 3.5 lbs
Noise Level: < 30 dB on Low setting
Warranty: 1-Year Limited Warranty

Controls and Settings

Control Panel located on the front of the base unit.

Buttons & Indicators: Power Button, Mist Control Dial (Low/High), Night Light Button, Filter Indicator Light.

Power: Press to turn unit On/Off. Unit beeps and display lights up.

Mist Control Dial: Rotate to adjust mist output. Low setting for quiet operation and longer run time. High setting for maximum moisture output.

Night Light: Press to toggle soft blue light On/Off. Independent of humidifier operation.

Filter Indicator Light: Illuminates when the wick filter needs replacement (typically every 1-2 months). Reset by pressing and holding the Power button for 5 seconds after filter change.

Automatic Shut-Off: Activates when water tank is empty or improperly seated. All lights will turn off.

Operation

For daily use, ensure the tank is filled and the filter is in good condition.

Check water level in the tank daily. Refill as needed.
Turn the unit On using the Power button.
Select desired mist level using the dial.
Adjust the mist nozzle direction as needed.
Use the Night Light if desired.
When not in use, or for refilling, press Power to turn unit off. Unplug from outlet.

Tip: For best performance, use distilled or demineralized water to reduce white dust and extend filter life.

Maintenance & Cleaning

Regular cleaning prevents mold and mineral buildup. Clean every 1-2 weeks, or more often in hard water areas.

Unplug the unit and remove the water tank.
Empty any remaining water from the base reservoir.
Clean the tank: Fill with a mixture of 1 cup white vinegar and 1 gallon water. Let sit for 20 minutes. Scrub interior with a soft brush. Rinse thoroughly.
Clean the base: Wipe the interior reservoir and all surfaces with a cloth dampened with the vinegar solution. Do not submerge the base in water.
Clean the mist nozzle with a cotton swab to remove any mineral deposits.
Rinse all parts with clean water and allow to air dry completely before reassembly.

CAUTION! Never use abrasive cleaners, bleach, or detergents. Do not immerse the base unit in water.

Filter Replacement

The wick filter should be replaced every 1-2 months, or when the Filter Indicator Light turns on.

Unplug the unit and remove the water tank.
Remove the old filter from the base by pulling it straight up.
Soak the new filter (Part # HWMF-340) in cool water for 15 minutes.
Insert the new filter into the slot in the base, ensuring it is fully seated.
Reset the Filter Indicator Light by plugging in the unit, then pressing and holding the Power button for 5 seconds until the light turns off.
Reassemble the tank and base.

Note: Using the humidifier without a filter or with an old filter can reduce performance and cause mineral dust.

Safety Information

Use only as directed in this manual.
Intended for indoor household use only.
Always unplug before cleaning, maintenance, or when not in use.
Do not operate with a damaged cord or plug.
Do not block mist nozzle or air intakes.
Keep out of reach of children and pets.
Do not add medications, essential oils, or fragrances to the water tank.
Use only clean, cool water. Do not use hot water.
Place on a flat, stable, water-resistant surface.
Do not move the unit while it is operating or full of water.

Regulatory Information

This device complies with Part 15 of the FCC Rules. Operation is subject to the condition that this device does not cause harmful interference. This product is listed by UL. Copyright © Honeywell International Inc. Honeywell and the Honeywell logo are registered trademarks of Honeywell International Inc. For customer support, visit www.honeywellpluggedin.com or call 1-800-332-1110.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No mist output	Empty tank, clogged filter, mist dial on Low	Refill tank, replace filter, turn mist dial to High.
Unit not turning on	Not plugged in, power outage	Ensure plug is secure in outlet. Check home circuit breaker.
White dust around unit	Hard water, old filter	Use distilled water. Replace wick filter.
Water leaking	Tank cap not tight, overfilled tank	Ensure tank cap is secure. Do not fill past MAX line.
Loud noise or gurgling	Low water level, mineral buildup	Refill water tank. Clean unit per instructions.
Filter light is on	Filter needs replacement	Replace wick filter and reset indicator.
Night light not working	LED failure, button not pressed	Press Night Light button. If still fails, contact support.
Automatic shut-off not working	Float valve stuck	Unplug, clean base reservoir, ensure tank is seated correctly.

Reset: Unplug unit for 2 minutes, then plug back in to reset electronics.

Service: For repairs not covered in troubleshooting, contact Honeywell Customer Support at 1-800-332-1110 or visit www.honeywellpluggedin.com. Do not attempt to disassemble the unit.