CHANTILLY, Va. — The Sheet Metal and Air Conditioning Contractors’ National Association (SMACNA) has published the third edition of “HVAC Systems — Testing, Adjusting and Balancing.” According to SMACNA, the manual provides fundamentals and procedures for balancing air systems.

The revised edition presents the fundamentals, methods, and procedures, including tables and charts, for balancing HVAC systems. Subjects covered in the manual include motor operation, fan curves, pump curves and fluid flow losses in ducts, fittings, pipes, and air terminals. Additionally, variable-frequency drives, direct digital control systems, lab hood exhaust balancing, and balancing equipment and procedures are presented.

For more information, visit www.smacna.org.