- 6 -
Installa
tion P
repar
ation
DUCT FITTINGS:
This Hood Must Use an
6" Round Duct. It Can
Transition to 3-1/4" x
10" or 3-1/4" x 12" Duct.
Use this chart to compu-
te maximum permissible
lengths for duct runs to
outdoors.
NOTE:
Do not exceed maxi-
mum permissible equivalent
lengths!
Maximum duct length:
100 feet for range ho-
ods.
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 in-
terruption of such naturally
vented systems, follow the
heating equipment manu-
facturer’s guidelines and
safety standards such as
those published by NFPA.
Duct
Piece:
Dimensions:
Equivalent
Number
Length*:
Quantity
Used:
Total
Equivalent
Length:
Round, straight 1 ft. (per foot
lenhgth)
3-1/4" x 10"
straight
1 ft. (per foot
lenhgth)
90° elbow
12 ft.
45° elbow
7 ft.
3-1/4" x 10"
3-1/4" x 12"
90° elbow
14 ft.
10 ft.
3-1/4" x 10"
3-1/4" x 12"
45° elbow
8 ft.
6 ft.
3-1/4" x 10"
3-1/4" x 12"
90° elbow
33 ft.
24 ft.
6" round to
rectangular
2 ft.
Rectangular to
8" round
2 ft.
3-1/4" x 10"
3-1/4" x 12"
6" round to
rectangular
transition 90°
elbow
4 ft.
4 ft.
3-1/4" x 10"
3-1/4" x 12"
Rectangular to
6" transition
90° elbow
4 ft.
4 ft.
Round wall
cap with
dramper
24 ft.
3-1/4" x 10"
3-1/4" x 12"
Rectangular
wall cap with
dramper
24 ft.
18 ft.
Round roof
cap
33 ft.
*Actual length of straight duct plus duct
fitting equivalent. Equivalent length of duct
pieces reflect requirements for good venting
performance with any ventilation hood.
Total Duct Run =
