ASHRAE 90571

Abstract

Preface Air terminal units play an important role in the energy consumption of a building and ultimately the comfort of occupants, both acoustic and thermal. This design guide was created with the goal of producing a best practice guide to aid in the selection of air terminal units by design engineers. The team that produced this guide comprised a consulting engineer, manufacturers of air terminal units, a balancing commissioning and testing engineer, and a manufacturer’s representative. This guide was written in regards to current North American codes, standards, and design practices. It is intended to aid design engineers in selecting types of air terminal units and to explain methods for sizing units while maximizing occupant comfort and energy efficiency. It also details how to meet sound requirements and how to estimate life-cycle costs. The authors’ intent was to cover the existing product base as well as new application and component improvements. ASHRAE Technical Committee (TC) 5.3, Room Air Distribution, is the cognizant committee that reviewed and ultimately voted to approve this guide. TC 5.3 is concerned with the distribution, diffusion, and conditioning of air within rooms and similarly treated spaces. It includes consideration of the principles of air distribution, air diffusion, and performance characteristics of all types of air terminal devices, fan-coils, active and passive beams, and high/low-pressure assemblies (air terminal units) or components, including associated or related accessories for both supply and exhaust air. TC 5.3 has developed information on air terminal units in ASHRAE Handbook—HVAC Systems and Equipment, ASHRAE Handbook—HVAC Applications, and ASHRAE Handbook—Fundamentals. This guide combines the information presented in these Handbooks and goes into more detail and analysis.