An air handling unit consists of multiple elements mounted on top of each other, which in turn make huge boxes called modules. These modules create the necessary ventilation requirements for purifying and cooling the building's indoor air. These units are usually installed on the roof of a building, and air is circulated through ventilation ducts. It is made of metal but painted to prevent corrosion. It contains all the components of the AHU. As the name suggests, filters are used to extract pollutants from the air. When customers have special requirements, use HEPA filter. Otherwise, use a bag filter, which filters the air very efficiently.

Other types of filters are panel filters, electrostatic filters and carbon filters. Due to the wide variety of wind turbines (backward, backward, forward, airfoil), designers use specialized software to check which type of wind turbine is most suitable based on the aesthetics of the building. With the advent of technology, VAV systems have become popular, which control the amount of air that is expelled. The VAV system also follows a greener agenda as it consumes less energy to run smoothly.

This is a physical location inside the AHU where the air returning to the AHU is mixed with the outside air to create the perfect air mix and then sent to the air conditioner again. Hybrid boxes help recover heat. Several other elements are also used to recover heat, such as cross-plate heat exchangers and heat wheels. It is one of the most important parts of the AHU. It is used to dehumidify and cool the air. Depending on the type of AHU system used, either refrigerated liquid cooling coils or direct expansion cooling coils can be used.

During harsh seasons like winter, the industrial air cooler inside the AHU frame and building can also become dry, which can be uncomfortable. That's where humidifiers come in. The mechanism of the humidifier includes: a steam grill, which heats water to produce steam, and a steam pot, which heats water using a heating pot and nozzles that spray water. The fan's electromechanical system then exhausts the air into the ducts that distribute the air throughout the building. Cooling is done using cooling coils through the air inside the ducts. Mufflers are also installed in the AHU to reduce noise from fans and filters.