X 1 40 ft.
Ductwork installation guide pdf.
90 elbow 10 ft.
For best results and ease of installation store the clamps gaskets and caulk at between 50 and 80 f.
Site condition and preparation it is not prudent practice to install underground duct work where ground water is present.
Duct pieces equivalent length x number used equivalent length wall cap 40 ft.
Leakage the time rate of air volume loss expressed in cubic feet per minute cfm l s.
X 1 3 ft.
1 psi equals 27 7 inches of water gauge.
Instructions install duct support system in leveled and squared curb.
This equal friction method of duct sizing should be adequate for normal residential furnace heating and air conditioning applications.
Contractors and specifiers who design and install duct systems although there is an abundance of published literature concerning mechanical.
Designers working alone are.
The following duct sizes are based on a fraction drop of 10 inches per 100 feet of lineal duct.
A common duct pressure of 0 25 inches water column is equal to 0 25 divided by 27 7 in wc psi 0 009.
Duct system design guide first edition 2003 mcgill airflow corporation mcgill airflow corporation one mission park groveport ohio 43125 duct system design i.
Ducts conforming to nfpa 90a or 90b shall meet the following requirements.
Ordinary heating ventilating and air conditioning duct systems read air pressures at 0 4 psi or less often much less.
The following chart describes an example of one possible ductwork installation.
Installation instructions a manufacturers printed instructions in accordance with the terms of their listing which advises the method and materials to install the flexible duct.
Checking the work œ quality control œ chapter 12.
X 2 20 ft.
Fabricate ductwork with 1 fl ange out on top opening and with an outside dimension that is smaller than inside dimension of duct openings cre ated by duct support system.
Equivalent lengths of duct pieces are based on actual tests.
13 to 51mm tough airstream surface resists shop installation and service damage sheet metal ducts must be tightly sealed fibrous glass duct liners are manufactured to.
Installation requirements 4 1 code reference the authority having jurisdiction should be referenced to determine what law ordinance or code shall apply in the use of flexible duct.
For installing in high ambient temperatures above 90 f consult aqc industries for special installation instructions.
Larger volumes or higher static pressures should be dealt with on an individual job basis.
Design documents œ instructions to the contractor œ insuring that the design documents convey to the hvac contractor what the designer wants by clarifying features shown on the drawings and described in the schedules and specifications.
Straight duct 3 x 10 rectangular 3 ft.
Listed a published list by a recognized approving.
