Add the new Aprilaire 400 Humidifier Annual Maintenance Kit to your order! This convenient kit gives you all the parts you need to maintain your Aprilaire 400 humidifier each year and keep it running in like-new factory condition.

The Aprilaire 400M Humidifier is one of eight updated humidifier models from Aprilaire. The Aprilaire 400 Humidifier is unique because it features a water-conserving design that does not require a drain line!

The Aprilaire 400M Humidifier includes a built-in bypass damper that is conveniently labeled for winter and summer settings. In addition, the Aprilaire 400 humidifier can humidify a tightly-constructed home of up to 4,000 square feet.

The Aprilaire 400M comes complete with the Aprilaire non-digital humidity control, one Aprilaire water panel, outdoor temperature sensor, saddle valve, 24V transformer, and installation instructions from Aprilaire!

Installation and Operating Manuals:
Click Here for Detailed Aprilaire 400A Humidifier Installation Instructions

Click Here for the Aprilaire Humidifier Owners Manual

Aprilaire Humidification Facts For Total Indoor Air Comfort

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