This is the component of common residential HVAC systems found indoors. It can typically be identified as a large gray metal box, and it’s most often found in the garage, attic, or within a small dedicated closet.
Also known as the “air handling unit,” the air handler is the primary machinery inside an HVAC system responsible for circulating conditioned air through interior spaces. Similar to furnace systems used for forced air heating in northern states, air handlers consist of a blower motor, fan, cooling and/or heating elements, evaporator coil, drain pan, circuit board, filtration elements, and pretty much any part of the system that affects temperature and moves the conditioned airflows. However, the air handler can only circulate heated air when paired with a heat pump. Air handlers come in a variety of configurations, with blower motors offering single or variable speeds.