Flex Duct Cfm Calculator

Equivalent duct calculator round vs rectangular.

Flex duct cfm calculator.

Read friction loss inches of water and duct velocity fpm. Other hart cooley mobile tools. Enter duct airflow cfm duct velocity fpm duct length and the number of bends. Input the required cfm in the box below that.

Enter round duct diameter. Flex duct 05 on most metal duct calculator round metal pipe 06 on most metal duct calculators field duct sizing chart rectangular sheet metal duct 07 on most metal duct calculators. Include fittings in the duct tel enter either. Enter the desired length of the rectangular duct.

Duct cross sectional area air flow rate and air speed are used in calculating the duct size. Enter air flow and its velocity in air duct sizing calculator to find the diameter of duct size. Read round duct diameter inches and friction loss per 100 of duct inches of water. Equivalent diameter is the diameter of a circular duct with similar pressure loss as an equivalent rectangular duct.

Cfm is flow rate in flex duct cubic feet per minute. Sheet metal duct friction loss calculator. Fpm is velocity in flex duct feet per minute. Friction loss calculator for sheet metal ducts.

Use the online duct calculator see references and calculate the needed flex duct size. Rectangular duct is rounded up to the nearest 1 4 inch. Friction loss calculator for flexible ducts. Calculations are for 60 f dry air at sea level from 5 to 3000 cfm approximately standard air which is 0 075lb da ft.

In wg duct tel. If ashrae 2013 is selected flexible roughness is 0 003 ft when straight and fully stretched tight at 0 compression adjusted at other compressions otherwise the. Data is based on straight runs of quietflex non metallic flexible air ducts as tested in accordance with the air diffusion council fd 72r1 test code and in accordance with ashrae 120 1999 method of testing to determine flow resistance of hvac. Friction rate velocity friction rate.

The flex duct size may be different than the hard duct that runs to that room. Air duct also termed as ductulator is a passage that is used to provide fresh air into rooms buildings etc air ducts may be in circular square and in rectangular shapes. Metal ductboard flex size by. Select the duct type on the pull down menu.

Based on duct diameter. Enter round duct diameter inches duct airflow cfm duct length and the number of bends. Read duct diameter inches and duct velocity fpm.