Air Handler

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Air Handler

What is Air Handler?

An air handler is a key HVAC component that circulates and conditions air in residential and commercial buildings for comfort and efficiency.

Description

An air handler, also known as an air handling unit (AHU), is a central component of an HVAC system responsible for circulating, filtering, and conditioning air throughout a building. It typically contains a blower, heating or cooling elements, filters, dampers, and controls that work together to manage indoor air distribution.

In construction projects, air handlers are used across residential, commercial, and industrial buildings to support heating and cooling systems. They work in conjunction with ductwork to deliver conditioned air to occupied spaces and return stale air back to the system for reconditioning. Air handlers can be installed indoors or outdoors and are often paired with heat pumps, chillers, or furnaces depending on the system design.

From a project and operational standpoint, properly sized and installed air handlers are critical to energy efficiency, indoor air quality, and occupant comfort. Poor selection or installation can lead to uneven temperatures, increased energy consumption, and premature equipment wear, making air handlers a key consideration during HVAC design and commissioning phases.

FAQs

  • What does an air handler do?

    An air handler circulates air through an HVAC system, filtering and heating or cooling it before distributing it throughout a building.

  • Is an air handler the same as a furnace?

    No. A furnace generates heat, while an air handler moves and conditions air. Some systems use both together.

  • Where is an air handler typically installed?

    Air handlers are commonly located in basements, attics, mechanical rooms, or on rooftops in commercial buildings.

  • Do air handlers include air filters?

    Yes, air handlers contain air filters that help remove dust, allergens, and other airborne particles.

  • Can an air handler work with a heat pump?

    Yes, air handlers are commonly paired with heat pumps to distribute heated or cooled air efficiently.

Fun Fact

Some large commercial air handlers are big enough to walk inside during maintenance — essentially functioning like mechanical “rooms” that move thousands of cubic feet of air per minute.

CSI Code

23 73 13

NAHB Code

3610