Regardless of the type of air conditioning system, the air is mainly conditioned in a/an:

The air handling unit (AHU) is the central component in most air conditioning systems responsible for the conditioning and distribution of the air. It typically contains a blower, heating and cooling elements, filter racks, and dampers to regulate airflow. The AHU processes the air by filtering out impurities, adjusting humidity levels, and either heating or cooling it to maintain desired temperature settings.

In various air conditioning systems, the AHU is key for ensuring that the air supplied to the indoor environment is comfortable and suitable for the occupants. This versatility makes it essential in both residential and commercial HVAC applications, handling air from the building and circulating it effectively.

Air purification chambers focus specifically on removing particulates and contaminants from the air but do not handle the conditioning or temperature regulation. Heat pump units are primarily involved in transferring thermal energy and may condition air but are not the main component responsible for air quality and distribution. Cooling towers, on the other hand, are used in industrial applications to remove heat from water that is then circulated through a building; they do not serve the function of directly conditioning air for indoor environments.

Thus, the air handling unit stands out as the component that is primarily responsible for the overall conditioning of the air in any air conditioning system.