GE Monogram ZV850 Installation Instructions Manual page 6

Installation Preparation
36" Island Vent Hood
Duct
fittincs
Use this chart to
compute maximum
permissable lengths
for duct runs to
outdoors.
Note: Do not exceed
maximumpermissable
equivalent lengths!
Maximum ductlength:
100 footforrange hoods.
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 ducfing.
Note:Any homeventilation
system, suchas 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 asthose
published by NFPAand ASHRAE.
Duct Piece Dimensions
Ro t/Ild,
straight
/_ 3-1/4" x 10"
straight
Q_ 90 ° elbow 12 It.
45 ° elbow 7 It.
3-1/4" x 10" 14 ft.
3-1/4" x 12" 10 It.
90 ° elbow
@_ 3-1/4" x 10"
8 ft.
3-1/4" x 12" 6tt.
45 ° elbow
3-1/4" x 10" 33 It. 3-1/4" x 12" 24 It.
90 ° fiat elbow
_@,_ 6" I'ound to
rectangular
2 It.
Equivalent Quantity
I,ength* Used
lit.
(per foot
length)
lit.
(per fbot
length)
_1_ Rectangular
to 6" round 2 It.
_ 3-1/4" x l 0" 4 ft.
3-1/4" x 12" 4 ft.
6" I'Ot/Ild to
rectangular
transition 90 ° elbow
_ 3-1/4" x 10" 4 ft.
3-1/4" x 12" 4ft.
Rectangular to 6" round
transition 90 ° elbow
Round
wall cap
with dainper 24 ft.
3-1/4" x 10" 24 ft. 3-1/4" x 12" 18 ft.
Rectangular wall cap
with damper
Round roof cap 33 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 __
Total
Equivalent
I,ength