GE JVB67HBB Installation Instructions Manual page 8

DUCTWORK LENGTH AND DUCT FITTINGS
NOTE: Do not exceed 150 foot maximum permissible equivalent lengths!
Flexible ducting: If flexible metal ducting is used, all equivalent feet values in the table should be
doubled. The flexible metal duct should be straight and smooth and extended as much as possible.
DO NOT use flexible plastic ducting.
Add equivalent lengths for all duct pieces and transitions used to ensure that the duct run does not
exceed the maximum 150 feet.
Duct
Pieces
6" Round
Straight
" x 10"
3 ⁄
1
4
Straight
6"
90° Elbow
6"
45° Elbow
" x 10"
3 ⁄
1
4
90° Elbow
SHOULD NOT EXCEED 150 EQUIVALENT FEET
*Equivalent lengths of duct pieces are based on actual tests conducted by GE Evaluation Engineering
and reflect requirements for good venting performance. See chart for CFM Duct Length.
Installation Instructions
Equivalent Duct
Length* Pieces
1 ft. (per
foot length)
1 ft. (per
foot length)
15 ft.
9 ft.
16 ft.
Equivalent
Length*
" x 10"
3 ⁄
1
4
5 ft.
45° Elbow
" x 10"
3 ⁄
1
4
24 ft.
90° Flat Elbow
6" Round
" x 10"
to 3 ⁄ 7 ft.
1
4
Transition
" x 10"
3 ⁄
1
4
to 6" Round 5 ft.
Transition
6" Round
" x 10"
to 3 ⁄
1
4
20 ft.
Transition
90° Elbow
13
Duct Equivalent
Pieces Length*
" x 10"
3 ⁄
1
4
to 6" Round
12 ft.
Transition
90° Elbow
6" Round
Wall Cap 21 ft.
with Damper
" x 10"
3 ⁄
1
4
Wall Cap 27 ft.
with Damper
6" Round
20 ft.
Roof Cap
6" Round
24 ft.
Roof Vent