Insignia NS-OTR16SS8Q Installation Manual page 8

Equivalent duct length table
To calculate your equivalent duct length:
1 Write the number of sections used for each of the duct pieces.
2 Multiply the number used by the equivalent length for each duct piece.
3 Add the total equivalent lengths together. This number must be less than 140 ft.
Straight duct 6" round
OR
3-1/4" × 10" rectangular
8
Duct Pieces
Rectangular-to-
round transition
adapter
Wall cap
90° elbow
45° elbow
90° elbow
45° elbow
Roof cap
www.insigniaproducts.com
Equivalent
× Number Used
Length
5 ft. × (
40 ft. × (
10 ft. × (
5 ft. × (
25 ft. × (
5 ft. × (
24 ft. × (
1 ft. × (
Total ductwork =
NS-OTR16SS8Q
Total
= Equivalent
Length
) = ft.
) = ft.
) = ft.
) = ft.
) = ft.
) = ft.
) = ft.
) = ft.
ft.
(For proper airflow, this
number should not
exceed 140 ft.)