GE ZVC42LSS - Manual (Page 10)

10
Advance Planning
DUCT FITTINGS
This Hood Must Use an
8" Round Duct. It Can
Transition to a
3-1/4" x 12" Duct.
Use this chart to compute
maximum permissible lengths for
duct runs to outdoors.
NOTE: Do not exceed maximum
permissible equivalent lengths!
Maximum duct length:
100 foot for range hoods.
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.
Total
Equivalent Quantity Equivalent
Duct Piece Dimensions Length* Used Length
Round, 1 ft.
straight (per foot
length)
3-1/4" x 12" 1 ft.
straight (per foot
length)
90° elbow
17 ft.
45° elbow
10 ft.
 ø[
90° elbow 43 ft.
3-1/4" x 12"
45° elbow 26 ft.
3-1/4" x 12"
90° flat elbow 102 ft.
8" round to
3-1/4" x 12" transition 2 ft.
3-1/4" x 12" to 8"
round transition 5 ft.
8" round
to 3-1/4" x 12"
transition 90° elbow 6 ft.
3-1/4" x 12" to 8"
round transition 90° elbow 13 ft.
Round
wall cap
with damper 32 ft.
3-1/4" x 12" wall cap
with damper 75 ft.
Round
roof cap 44 ft.
Total Duct Run
* 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.