An air handling system is a type of mechanical system that is used to condition and circulate air as part of a heating, ventilation, and air conditioning (HVAC) system. It is responsible for controlling the temperature, humidity, and quality of the air within a building. An air handling system is composed of several components, including a fan, filter, and air handler. The fan is responsible for drawing air into the system and pushing it through the filter, which removes dust, pollen, and other airborne particles. The air handler is then used to heat or cool the air, depending on the season and desired temperature. The air is then distributed throughout the building, providing a comfortable and healthy environment for occupants. An air handling system is a critical component of any HVAC system, as it helps to ensure that the air in a building is clean and comfortable.