Honeywell Humidifier HCM645 - 4 Gl. Cool Mist Manual

The Honeywell HCM645 is a 4-gallon cool mist humidifier designed to add moisture to dry indoor air, helping to relieve dry skin, nasal congestion, and static electricity. It features a large tank capacity, adjustable humidity control, a wicking filter, an easy-to-fill top-fill design, a quiet operation mode, an automatic shut-off when empty, and a refill indicator light. Below are key sections for safety, features, setup, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: 4-gallon water tank, wicking filter, adjustable humidistat, top-fill opening, control panel, mist outlet, refill indicator, and power cord.

Installation & Setup

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

1. Remove all packaging materials from inside and outside the unit.
2. Install the wicking filter: Remove filter from packaging, soak in cool water for 15 minutes, then insert into filter frame.
3. Fill the tank: Remove tank cap, fill with cool, clean tap water (do not use hot water or additives). Replace cap securely.
4. Place tank on base: Align tank with base and set down gently.
5. Plug into a 120V AC outlet.

WARNING! Use only on a level, waterproof surface. Do not place near heat sources or in direct sunlight.

First-Time Use

After setup, follow these steps to begin operation.

1. Turn the control knob to the desired mist setting (Low, Medium, High).
2. Adjust the humidistat dial to your preferred humidity level (typically 40-60% RH).
3. Allow a few minutes for the filter to fully saturate and mist to begin emitting.
4. Monitor the refill indicator light; refill when illuminated.

CAUTION! Always unplug the unit before refilling, cleaning, or performing any maintenance.

Specifications

• Model: HCM645
• Tank Capacity: 4 gallons (15.1 liters)
• Coverage Area: Up to 1,200 square feet
• Run Time: Up to 24 hours on low setting
• Mist Output: Adjustable up to 2.3 gallons per day
• Filter Type: Wicking filter (replacement part #HCM-645F)
• Power: 120V AC, 60Hz, 30W
• Dimensions (approx.): 15.5" H x 13.5" W x 10.5" D
• Weight (empty): 8.5 lbs (3.9 kg)
• Noise Level: < 35 dB on low setting

Controls and Operation

Control Panel: Power/Mist Control Knob, Humidistat Dial, Refill Indicator Light.

Operation: Turn knob clockwise to increase mist output (Low → Medium → High). Turn humidistat to set target humidity. The unit will cycle on and off to maintain the set level.

Indicator Light: Green = Normal operation. Red/Illuminated = Tank empty, needs refill.

Automatic Shut-Off: Activates when tank is empty or removed, preventing damage to the motor.

Maintenance & Cleaning

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

1. Unplug the unit.
2. Empty any remaining water from tank and base.
3. Clean tank with a mixture of mild dish soap and warm water. Rinse thoroughly.
4. Wipe base interior with a soft cloth dampened with white vinegar or a humidifier cleaner to remove scale.
5. Rinse all parts with clean water and air dry completely before reassembly.
6. Clean every 1-2 weeks during use, or more often in hard water areas.

Tip: Never use abrasive cleaners, bleach, or submerge the motor unit in water.

Filter Replacement

The wicking filter should be replaced every 1-2 months, or when discolored or clogged.

1. Unplug humidifier and remove water tank.
2. Remove the old filter from the filter frame.
3. Soak the new filter (HCM-645F) in cool water for 15 minutes.
4. Insert the damp filter into the frame, ensuring it is seated properly.
5. Reassemble the unit and refill with water.

WARNING! Using a dirty or clogged filter reduces mist output, increases noise, and can harbor bacteria.

Safety Features

Automatic Shut-Off: Prevents operation when tank is empty or improperly seated. Tip-Over Protection: Internal switch cuts power if unit is knocked over. Cool Mist Technology: Emits room-temperature mist, safe for children and pets.

Care & Storage

When not in use for extended periods:

1. Unplug, empty, and thoroughly clean all parts (see Maintenance).
2. Allow all components to air dry completely.
3. Remove and discard the old filter.
4. Store unit in original box or a dry place, with tank cap off to prevent odors.

CAUTION! Never store with water in the tank. Always dry completely to prevent mold growth.

Regulatory Information

This humidifier complies with Part 15 of the FCC Rules. Operation is subject to the condition that this device does not cause harmful interference. Copyright © Honeywell International Inc. Honeywell and the Honeywell Home logo are trademarks of Honeywell International Inc. For support, visit www.honeywellhumidifiers.com or contact 1-800-332-1110.

Troubleshooting

Reset: Unplug for 1 minute, then restart.

Service: 1-800-332-1110; www.honeywellhumidifiers.com