ARLINGTON, Va. - The Air Conditioning Contractors of America Educational Institute (ACCA-EI) Standards Task Team (STT) announced an American National Standards Institute (ANSI) public review period for its standard for residential HVAC system zoning. This standard provides the step-by-step procedures for the design of optimum zoning in residential structures. The public review period will close at 11:59 p.m. EDT on July 4.

This proposed standard was created for mechanical and HVAC system designers and addresses requirements of zoning design that include:

• Zonal load calculations;

• Zoning strategies and protocols (diversity issues; multilevel construction, diverse floor plans; winter/summer room and zone cfm variations; etc.);

• Zoned systems types/attributes (multiple furnaces or refrigeration cycle units, central heating-cooling with VAV dampers, and split coil refrigeration cycle with multiple indoor coils);

• Controls and control strategies (VAV bypass air; VAV damper sizing; multi- or variable-speed; and airflow management); and

• Zonal duct design elements, as well as supply and return grille selection (constant volume vs. VAV).

This proposed standard is referenced as BSR/ACCA 11 Manual Zr-201x, and can be downloaded at Comments must be submitted using the ACCA response form, by 11:59 p.m. EDT on July 4.

Publication date:06/06/2011