You cannot find too many Aprilaire Humidifiers on sale online, or off. Those models are often very expensive, and the Aprilaire Model 400A is not any different.
While many humidifiers have the capacity to humidify one room, the aprilaire humidifiers can actually Humidify the whole house. They have the new bypass damper, that helps you get the most out of vapor, and lower the usage of the water.
The Aprilaire Model 400A has a 100% automatic control. This unit evaporates around .70 Gallons per hour. It can humidify homes that are very large, up to 4000 Sq. Ft. in size.
