Ductwork; Duct Fittings - GE Monogram ZVB36 Installation Instructions Manual

Ductwork
Use this form to
compute maximum
permissible lengths
for duct runs to
outdoors.
Nete: Do not exceed
maximum permissible
equivalent lengthsT
Flexibme dactiag:
If flexible metal
ducting is used, aH the
equivalent feet values
in the table should be
doubled. The flexibUe
metal duct should be
straight and smooth
and extended as
much as possible.
Do NOT use flexible
plastic ducting.
I)ewndraft Vent
150' maximum
equivalent length
Nete: Any home
ventilation system,
such as a cooktop with
a downdraft exhaust
mechanism, 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 inter°
ruption of such
naturally vented
systems, follow the
heating equipment
manufacturer's
guidelines and safety
standards such as
those published by
NFPA and ASHRAE.
Total
Equivalent Quantity Equivalent
Duct Piece Dimensions Length* Used Lengtb
I ft.
6" round, (per foot
straight lengtb}
I ft.
3-!/4" x I0" (per foot
straight length)
6"
96° elbow I5 ft.
45° elbow 9 ft.
3-!/4" x 16"
96° elbow I6 ft.
3-I/4" x 10"
45° elbow 5 ft.
3-!/4" x I0"
96° flat elbow I8 ft.
6" round
to 3-1/4" x 10'
transition 7 ft.
3-I/4" x I6"
round to 6"
transition 5 ft.
6" round to
transition
90° elbow 20 ft.
_& 3-I/4" x I6" to 6"
round transition
96° elbow I2 ft.
6" round
wall cap
with damper 21 ft.
3-I/4" x I0"
_ wa,I cap
with damper 27 ft.
6" round roof cap 20 ft.
6" round
roof vent 24 ft.
_ActuaJ length of straight duct plus duct fitting Total Duct Run
equivalent. Equivalent Jengtb of duct pieces are based
on actual tests conducted by GE Evaluation Engineer-
ing and reflect requirements for good veering
performance with any downdraft cooktop.
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