What is the difference between makeup air unit and air handling unit?

A Makeup Air Unit (MAU) is specifically designed to bring in outside air to replace air that is exhausted from a building, ensuring proper ventilation and indoor air quality. In contrast, an Air Handling Unit (AHU) is a broader system that conditions and circulates air within a building, often incorporating heating, cooling, filtration, and humidity control. While MAUs primarily focus on introducing fresh air, AHUs manage the overall air quality and comfort within the indoor environment. Both units play important roles in HVAC systems but serve different functions.