The definition of air handling unit from ANSI/AHRI Typical 430-2009 states that it's “A manufacturing facility-created encased assembly consisting of a fan or followers together with other needed machines to accomplish a number of on the features of circulating, cleaning, heating, cooling, humidifying, dehumidifying and mixing of air….” Modular AHUs https://air-handling-units-ahus94815.getblogs.net/64935764/5-easy-facts-about-air-handling-units-ahus-described