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 3
1
⁄4″ x 10″ 90° Elbow 5 ft.
(15.24 cm to 8.26 cm x 25.4 cm) (1.52 m)
3
1
⁄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 3
1
⁄4″ x 10″ Transition 1 ft.
(15.24 cm to 8.26 cm x 25.4 cm) (0.30 m)
3
1
⁄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 3
1
⁄4″ x 10″ 90° Elbow 6 ft.
(12.7 cm to 8.26 cm x 25.4 cm) (1.83 m)
3
1
⁄4″ x 10″ 90° Elbow 5 ft.
(8.26 cm x 25.4 cm) (1.52 m)
3
1
⁄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)
3
1
⁄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)
3
1
⁄4″ x 10″ Straight Duct–Feet 1 ft.
(0.30 m)
System Total
