The Definitive Guide on Air Terminal Units

ASHRAE Design Guide for Air Terminal Units provides detailed guidance for selection, application, control, and commissioning of a common element in all-air HVAC systems—the air terminal unit (ATU). It was written with a view toward current codes, standards, and design practices and is intended to aid design engineers in sizing units while maximizing occupant comfort and energy efficiency. This guide can be used as a complete, comprehensive in-house training program for new designers, and experienced engineers and designers can navigate directly to chapters of interest. New design paradigms are introduced throughout.

This guide includes detailed discussion on the criteria the design engineer needs to properly schedule and specify ATUs; with proper selection, the engineer can design a better system, resulting in acceptable sound levels, improved flow volume control, proper ATU sizing, and optimized energy consumption. The guide covers the history and types of ATUs as well as ATU construction types, insulation options, installation methods and suggestions, and accessories. Also included are in-depth treatises on HVAC acoustics, the control options and recommended sequences of operations for various ATUs and systems, comparing manufacturers' ratings, building energy modeling, and life-cycle cost analysis. ASHRAE, AHRI, and AABC standards applicable to ATUs; testing, balancing, and commissioning for ATUs; and ATU applications are also covered in this comprehensive resource. This design guide is accompanied by supplemental materials online for ongoing guidance.