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AprilAire 400 Whole-Home Humidifier

Automatic WATER SAVER Furnace Humidifier
The Model 400 is a drain-free humidifier, featuring evaporative technology to minimize water use.

AprilAire introduced the first evaporative humidifier for forced air furnace systems back in 1954. Since that time, AprilAire continues to lead the industry in whole-home humidification systems. Our evaporative humidifiers work by piping water into the distribution tray located at the top of the humidifier. The water is uniformly distributed across the width of the tray and through a scientifically designed system of outlets. It flows by gravity over the water panel evaporator. Dry, hot air from the HVAC system is moved through the moisture-laden water panel evaporator. Natural evaporation takes place, the water is turned to vapor, and the humidified air is circulated throughout your home.

Included in the box: Installation instructions and template, humidifier with built-in bypass damper, 24 VAC transformer, automatic digital humidifier control, and outdoor temperature sensor, saddle valve, solenoid valve, and water panel

Model 400 features:

BUY WITH CONFIDENCEThis humidifier was designed and manufactured in the U.S.A. by AprilAire – the inventor of the whole home evaporative humidifier, and the leader in indoor air quality solutions
CONSERVES WATERusing a unique evaporation process that also eliminates the need for a floor drain
FULL COVERAGEup to 2,500 square feet in average constructed homes* with a capacity of 17 gallons per day
AUTOMATIC HUMIDIFIERwith dual sensors to monitor and respond to both outdoor temperature and indoor relative humidity to deliver optimum humidity 24/7 throughout the home – simply set it and forgetit
CONVENIENT DIGITAL CONTROLshows percent humidity, lights indicate humidifier is running, when to change the water panel, when service is needed, and Blower Activation switch sets humidifier to run continually, or only when the furnace runs
HUMIDITY FOR HEALTHAprilAire Humidifiers can help you maintain the optimal humidity in your home between 40% – 60% minimizing the formation of bacteria, dust mites, fungi, and viruses. This helps reduce the incidence of respiratory infections andsymptoms related to allergies and asthma. In addition, you’ll feel more comfortable while also preserving items in your home susceptible to damage from changing humidity or dry conditions.

*AHRI Guideline F for Average Construction homes, https://www.ahrinet.org/App_Content/ahri/files/Guidelines/AHRI_Guideline_F_SI_2015.pdf

Humidity for Health

Reduce the incidence of respiratory infections and symptoms related to allergies and asthma by minimizing the formation of bacteria and viruses, fungi, and dust mites.

Humidity for Comfort

Whether your home is in a dry region of the country, or in an area with seasonal dryness, maintaining the right level of humidity can make all the difference in how comfortable you feel in your home.

Humidity for Preservation

Help preserve the natural beauty of wood floors, cabinetry, furnishings and anything else in your home susceptible to warping, cracking, or other permanent damage due to dry air.