Introduction

Thank you for your recent Aprilaire® Humidifier purchase. We sincerely appreciate your business and are pleased to add your name to our growing list of customers. With this purchase, you have invested in the highest quality equipment currently available. Research Products Corporation is the largest manufacturer of whole house humidifiers, air cleaners, and energy recovery ventilators and is a recognized leader in the heating and air conditioning industry today.

Please be assured that in addition to product quality, we are also committed to unit performance as well as customer satisfaction. Your unit will require periodic maintenance to assure you of continued fine performance. Please proceed as shown on page 9 to obtain service parts and/or replacement Water Panel® evaporators.

Now, please take a few minutes and read the appropriate section of this booklet. This will familiarize you with the benefits you will receive from the equipment you just purchased and help you understand the routine maintenance that will be required. Be sure to register your Humidifier with us for our records and your protection. You may do so by registering online at: www.aprilaire.com/warranty.

Genuine Replacement Water Panel® evaporators are available from your installing contractor or from most other heating and air conditioning contractors in your area. However, if you still have difficulty in obtaining a replacement Water Panel evaporator, use the dealer locator in our web site (www.aprilaire.com) or look in the Yellow Pages under Humidifying Apparatus or Heating & Air Conditioning Contractors. Purchase only genuine Aprilaire Water Panels to maintain performance.

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400 specifications

The Aprilaire 400 is a high-performance whole-home humidifier designed to enhance indoor air quality and provide superior comfort throughout your living spaces. As part of the Aprilaire family, known for their commitment to creating healthier environments, this model stands out due to its innovative features and advanced technologies.

One of the main characteristics of the Aprilaire 400 is its capacity to humidify homes effectively, covering an area of up to 4,000 square feet. This makes it ideal for large living spaces, ensuring that every room benefits from balanced humidity levels. The humidifier operates seamlessly with the home’s existing heating and cooling systems, requiring no additional maintenance, making it a hassle-free solution for homeowners.

A prominent feature of the Aprilaire 400 is its self-regulating technology. This unit uses a built-in humidistat that senses the moisture levels in your home and adjusts the humidification output accordingly. This ensures optimal humidity—typically between 30% and 50%—which can help reduce issues related to dry air, such as dry skin, irritated sinuses, and static electricity.

Another key benefit of the Aprilaire 400 is its evaporative design, which utilizes a water panel rather than a traditional water tank. This allows for efficient moisture dispersion, as the humidifier draws in dry air, passes it through the water panel, and releases it back into the living space as humidified air. The water panel is replaceable and designed for annual maintenance, promoting long-term functionality and hygiene.

The Aprilaire 400 also incorporates a simple installation process. With compatibility for various heating systems, including forced air and hydronic, it can be integrated into most homes without significant modifications. Its compact design is another advantage, ensuring it can fit unobtrusively in your home, maintaining the aesthetic of your space.

Overall, the Aprilaire 400 whole-home humidifier is a reliable solution for maintaining optimal humidity levels, fostering a healthier living environment, and enhancing overall comfort. With its advanced features, ease of use, and efficient operation, this humidifier is a smart investment for any homeowner aiming to improve indoor air quality and promote well-being.