Owner's Manual

DUCT FITTINGS
Use this chart to compute
maximum permissable lengths for
duct runs to outdoors.
NOTE: Do not exceed maximum
permissable equivalent lengths!
Maximum duct length:
100 foot for 6” round duct
75 foot for 3-1/4” x 12” duct
Flexible ducting:
If flexible metal ducting is used,
all the 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.
NOTE: Any home ventilation
system, such as a ventilation
hood, may interrupt the proper
flow of combustion air and
exhaust required by fireplaces,
gas furnaces, gas water heaters
and other naturally vented
systems. To minimize the chance
of interruption of such naturally
vented systems, follow the heating
equipment manufacturer’s
guidelines and safety standards
such as those published by NFPA
and ASHRAE. When applicable,
install any makeup (replacement)
air system in accordance with local
building code requirements. Visit
GEAppliances.com for available
makeup air solutions.
This Hood Must Use a
6” Round Duct.
It Can Transition To
3-1/4” x 12” Duct
5
Installation Preparation
Total
Equivalent Quantity Equivalent
Duct Piece Dimensions Length* Used Length
Round, 1 ft.
straight (per foot
length)
3-1/4” x 12” 1 ft.
3-1/4” x 24” (per foot
straight length)
6” Round
90° elbow 15 ft.
6” Round
45° elbow 8 ft.
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90° elbow 11 ft.
3-1/4” x 12” or
45° elbow 6 ft.
3-1/4” x 12”
90° flat elbow 24 ft.
6” round to
3-1/4” x 12”
or 3-1/4” x 24” transition 1 ft.
3-1/4” x 12” to 6”
round transition 8 ft.
6” round
to 3-1/4” x 12” or
transition 90° elbow 16 ft.
3-1/4” x 12” to 6” round
round transition 90° elbow 17 ft.
6” round
wall cap
with damper 30 ft.
3-1/4” x 12” wall cap
with damper 30 ft.
6” Round
roof cap 26 ft.
6” Round
roof vent 26 ft.
* Actual length of straight duct plus duct
fitting equivalent. Equivalent length of
duct pieces are based on actual tests
conducted by GE Evaluation Engineering
and reflect requirements for good venting
performance with any ventilation hood.
Total Duct Run