Alexandria, VA (July 29, 2025) — The Air Conditioning Contractors of America Educational Institute (ACCA-EI) Standards Task Team (STT) announces an American National Standards Institute (ANSI) public review period for proposed revisions to ANSI/ACCA 11 Manual Zr® – 2018, Residential Zoning, as a revised industry standard.
The 30-day ANSI public review period will run from July 25 through August 24, 2025.
This is the first public review for proposed revisions to Manual Zr® – 2018, and only involves correcting an error in the formula in Figure 2-2 related to Air - Air Cooling referenced under Section N2-9, Bypass Duct Relief.
Manual Zr® provides procedures and requirements for designing zoned comfort systems for residential buildings, including single-family detached homes, duplex and triplex homes, row and townhouses, and large, multi-family structures that are in accordance and compatible with Manual J® procedures.
Get a copy of the proposed correction to the formula and submit comments by going to the link below and using the form.
ACCA ANSI Public Response Form - Proposed Revisions to Manual Zr®
For more information about Manual Zr® or ACCA, please contact Samantha Boyd, ACCA director of communications, marketing, and member engagement, at samantha.boyd@acca.org or 703-824-8842.