GE ZV950 Installation Instructions Manual page 6

installation Preparation
DUCT FiTTiNGS
Use this chart to compute maxhnmn
permissible lengths for duct runs to
O tltdooYs.
Note: Do not exceed maximum
equivalent lengths!
Maximum duct length:
100 ft. for range hoods.
?ermissible
Flexible ducting:
If flexible metal ducfing is used, all
the equivalent feet values in the ruble
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 homeventilation system,suchas a ventilation
hood,may interruptthe properflow of combustionair and
exhaustrequiredbyfireplaces,gas furnaces,gas water
heatersand other naturallyvented systems.To minimize
the chanceof interruptionof suchnaturallyvented
systems,follow the heating equipmentmanufacturer's
guidelinesand safetystandardssuchasthose published
by NFPA andASHRAE
Duct Piece Dimensions
Round,
straight
3-1/4" x 12"
straight
(_ 90 ° elbow
(_ 45 ° elbo_a
3-1/4" x 12"
90 ° elbo_
%
©
Equivalent
Length*
IIL
(per foot
length)
lft.
(per foot
length)
17 ft.
10ft.
43 ft.
Quantib_
Used
3-1/4" x 12"
45 ° elbox_ 26 ft.
3-1/4" x 12"
90 ° flat elb{m 102 ft.
_" I'Ot/lld to
3-1/4" x 12" transition 2 ft.
3-1/4" x 12"
to 8" round transition 5 ft.
_" I'OHlld
to 3-1/4" x 12"
transition
90 ° elbow 6 ft
3-1/4" x 12" to 8"
3 I'Ot/lld transition 90 ° elb(m 1: ft.
Round
wall cap
with damper
32 ft.
3-1/4" x 12" x_all cap
x_ith damper
75 ft.
Total
Equivalent
Length
Round
roof cap
44 ft.
"Actual length of straight duct plus duct fitting equivalent.
Equivalentlength of duct pieces are basedon actual
tests conducted by GEEvaluationEngineeringand reflect
requirementsfor good venting performancewith any
ventilation hood.
Total Duct Run
6