Air conditioner basics

An Air Handling Unit (AHU) or Air Handling is a device that regulates and circulates air as part of a heating, ventilating, and air-conditioning (HVAC) system. It is a large metal box containing a blower, heating or cooling elements, filter racks or chambers, sound attenuators, and dampers. It connects to a ductwork ventilation system that distributes the conditioned air through the building and returns it to the AHU.