Good direct-gas-fired-AHU applications include facilities/processes that have high exhaust/infiltration airflows, large open spaces with few smaller spaces, and no low-humidity-control requirements. As noted previously, direct gas-fired AHUs commonly are used in commercial kitchens. Other commercial facilities that might benefit from utilizing direct gas-fired AHUs include fitness centers/gyms, enclosed stadiums, auditoriums, large retail stores, car dealerships, airport terminals, and laboratories.


Though the consequences of poorly designed or installed direct gas-fired AHUs can be severe and possibly deadly, those that are well-designed and installed can provide economical, energy-efficient, and reliable service for the right applications.


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An engineering manager with Jacobs Engineering Inc., Vincent A. Sakraida, PE, LEED AP, has 25 years of experience designing mechanical systems for high-technology facilities, as well as extensive experience designing central-plant, laboratory-utility, and HVAC systems.