ACCA
ACCA Manual D
Published by Air Conditioning Contractors of America (ACCA)
acca.org · checked 2026-09-23
Citing it here is not conformity with it, and this site holds no copy of its text.
- 4Calculators cite it
What it governs
The residential duct design procedure: sizing a duct system so that each room receives the airflow the heat-loss and heat-gain calculation asked for, at a static pressure the equipment can actually deliver. It follows the load calculation and the equipment selection rather than replacing them — a duct designed to this procedure against the wrong load is a well-sized route for the wrong quantity of air.
Its output is a duct layout and sizes, not a comfort guarantee: what leaves the register is governed here, what happens in the room is not. Flexible duct is where designs most often fail in the field: its effective length depends on how it was installed, and a run that is compressed or sagging delivers a fraction of the air the design allowed for.
Return air is half the system and gets a fraction of the attention. A room with supply and no path back to the return is pressurised, and the design airflow never arrives however carefully the supply was sized.
Obtained from Air Conditioning Contractors of America. What ACCA publishes
Editions
This site holds no edition list for ACCA Manual D, so a citation here names ACCA Manual D rather than a year. The publisher above has the current designation.
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