ARLINGTON, Va. - The first in a four-part series of technical bulletins regarding direct-fired make-up air (MUA) equipment is available at the Air Conditioning Contractors of America's (ACCA) Web site.
ACCA Technical Bulletin 109 covers specifications for and operation of direct-fired MUA equipment in situations where one or more HVAC systems exhaust air from the space and require an equivalent amount of outdoor air (or make-up air) to maintain comfort, air quality, and equipment performance. Many commercial and industrial spaces have substantial make-up air or air-change requirements. These include manufacturing plants, garages, aircraft hangars, kitchens, shopping malls, and some warehouses.