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Duct Fitting Database

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Note: multiple user licensing is not available for this product. 

The ASHRAE Duct Fitting Database, with cloud-based access by annual subscription, includes loss coefficient tables for more than 200 round, rectangular, and flat oval duct fittings.

Featuring pictorial outlines of each fitting, this database is useful to design engineers dealing with a variety of duct fittings. For any given fitting, enter the flow rate and fitting information and obtain loss coefficient data and associated pressure loss. The product includes table data for supply, exhaust, and common (supply/return) duct functions. Fittings may be saved into a project file, which is easily navigated and can be stored and transferred.

The database interface features fully available input, output, calculations, and table data properties; and easily viewable calculations that update in real time.

Purchasers receive a one-year subscription for cloud-based access to the ASHRAE Duct Fitting Database ver. 6.00.05.

Get the App for your iPhone, iPod, or iPad

ASHRAE Duct Fitting Database (DFDB) for the iPhone, iPod touch, and iPad allows you to perform pressure loss calculations for ASHRAE duct fittings in both I-P and SI units. Use this mobile app in the field for quick duct pressure loss calculations. The inputs can be adjusted by touch, and installation is automatic. Purchase this product from iTunes for $9.99 Learn More

The Standard

Standard 120-2017 --Method of Testing the Determine Flow Resistance of HVAC Ducts and Fittings
ASHRAE Standard 120 establishes uniform methods of laboratory testing of HVAC ducts and fittings to determine their resistance to airflow.

Also Available

The Duct Size Calculator is a quick reference tool for approximating duct sizes and equivalent sizes of sheet metal duct versus flexible duct. It includes sizing for metal ducts, and for flexible duct when compressed at 4%, 15%, and 30% straight line compression. The Duct Size Calculator is the result of collaboration between ASHRAE TC 5.2, Duct Design, and the Air Distribution Institute. Learn more