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Aprilaire Humidifier, 24V Whole House Humidifier w/ Manual Control - 0.7 Gallons/hr

Aprilaire 400M

SKU: 826494
Our Price: $155.00
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Aprilaire 400M


Product Information:

About The Aprilaire 400M 120V Hang-Mount Whole-House Humidifier

The Aprilaire 400M 24V Whole-House Humidifier utilizes a unique evaporative technology that reduces the water usage by passing through the built in bypass damper.  During the water processing the water is naturally pulled down by gravity while at the same time the water panel draws the water back to the top allowing the Aprilaire 400M 24V Whole-House Humidifier to use 100% of the water that is delivered to the unit.  The Aprilaire 400M 24V Whole-House Humidifier can help to solve common house issues such as chipping paint/plaster, splitting/cracked wood floors, splitting/cracked wood furniture, splitting/cracked trim and molding.  The Aprilaire 400M 24V Whole-House Humidifier can also help with many health issues such as sore throats, cry nose, cracked/itchy skin, allergies and asthma symptoms.  The Aprilaire 400M 24V Whole-House Humidifier includes a built-in bypass damper, saddle valve, one water panel, 24 volt transformer, manual humidifier control and the installation sheet.

Highly Efficient For Better Results

By evaporating up to 0.7 gallons of water per hour, you will never have to experience the discomfort of dry air again! Best of all, the wide ranging effects of this humidifier can reach every room in a well-constructed home of up to 4,000 square feet!  If you worry about water conservation or live in a region where standing water is a problem, don’t wait another day to get the Aprilaire 400M Humidifier.  This great humidifier not only recycles water cleanly into the air, but can help eliminate water where draining is not available.

Benefits for Your Home & Your Health

By maintaining an optimal level of humidity you can ensure proper respiratory health, and avoid expensive repairs on parts of your home that can be affected by dry weather, parts such as weather stripping, molding, paint, etc.  Keeping your Aprilaire humidifier maintained allows your humidifier to provide optimal performance.

Minimal Maintenance

The Aprilaire 400M Humidifier does not require that you focus a lot of your time maintaining the unit.  The Aprilaire humidifier should be visually checked every 500 hours, more frequently during heavy use.  The water lines and plumbing components should be checked for cracks or leaks and replaced as needed.  The one item that must be replaced regularly is the water panel.  The water panel should be replaced once a year during regular use, and every six months during extreme use.

Please Note: Heat pumps: Model 400 can be installed in heat pump applications. However, due to the fact that heat pumps deliver lower temperature air to the home than gas furnaces, evaporation will be approximately 60% of rated capacity. (With other Aprilaire models hot water can be used instead of cold to maximize evaporation. However, due to the nature of the wicking water panel in the Model 400 hot water provides no extra benefit.) As such, your dealer will need to take the size and age of your home into consideration to ensure the Model 400 will provide satisfactory comfort and protection through adequate humidification.

Additional Information:





• Eliminates standing water, making it the perfect choice for homes with septic systems, locations where a floor drain is not available or families interested in water conservation
• Features Manual Control
• Has an evaporation capacity of 0.70 gallons per hour
• Humidifies tightly-constructed homes up to a 4,000 square foot in size
• Needs no drain panel uses 100 percent of humidifier water


• Sq. Ft. Area (air changes/hr.): 1,000 loose house (2) / 2,000 avg. house (1) / 4,000 tight house (1/2)
• Unit Size (inches): 15-3/8W x 15-3/4H x 10-1/4D 6" dia. round opening
• Plenum Opening (inches): 10W x 12-3/4H
• Water Evap Rate: 0.70 gph
• Water Feed Rate: N/A
• Electrical Data: 24V-60Hz 0.5 AMP

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