The answer to 'what is air handler' is an air handler, also known as an air handling unit (AHU), is a key component of a central heating, ventilation, and air conditioning (HVAC) system. An air handler is responsible for circulating and conditioning the air throughout a home or building. It consists of a blower, heating and/or cooling elements, filter racks or chambers, and dampers to control the flow of air.
The air handler is typically located within the home, often in the attic, basement, or a dedicated utility closet. It works in conjunction with the outdoor condenser unit to provide heating, cooling, and air circulation. The blower in the air handler pulls in air from the return ducts, passes it over the heating or cooling coils, and then pushes the conditioned air through the supply ducts and into the living spaces.