25
Installation Instructions
DUCT LENGTH CHART
Duct Fitting Number Total Equivalent
Duct Fitting Equivalent Length of Fittings Length of Fitting
8″Diameter 90° Elbow 5 ft.
(1.52 m)
6″Diameter 45° Elbow 2.5 ft.
(0.76 m)
5″to 6″Transition 1 ft.
(12.7 cm to 15.24 cm) (0.30 m)
6″to 31⁄4″ x 10″90° Elbow 5 ft.
(15.24 cm to 8.26 cm x 25.4 cm) (1.52 m)
31⁄4″ x 10″to 6″90° Elbow 9 ft.
(8.26 cm x 25.4 cm to 15.24 cm) (2.75 m)
6″to 31⁄4″ x 10″Transition 1 ft.
(15.24 cm to 8.26 cm x 25.4 cm) (0.30 m)
31⁄4″ x 10″to 6″Transition 4.5 ft.
(8.26 cm x 25.4 cm to 15.24 cm) (1.37 m)
5″to 31⁄4″ x 10″90° Elbow 6 ft.
(12.7 cm to 8.26 cm x 25.4 cm) (1.83 m)
31⁄4″ x 10″90° Elbow 5 ft.
(8.26 cm x 25.4 cm) (1.52 m)
31⁄4″ x 10″Flat Elbow 12 ft.
(8.26 cm x 25.4 cm) (3.66 m)
6″Wall Cap 28 ft.
(15.24 cm) (8.53 m)
31⁄4″ x 10″Wall Cap 20 ft.
(8.26 cm x 25.4 cm) (6.10 m)
10″ x 10″Roof Jack 0 ft.
(25.4 cm x 25.4 cm) (0 m)
Thermal Break 2 ft.
(0.61 m)
6″Diameter Straight Duct–Feet 1 ft.
(For flex duct multiply by 2.) (0.30 m)
31⁄4″ x 10″Straight Duct–Feet 1 ft.
(0.30 m)
System Total