GE JVM1650BB005 Installation Instructions Manual page 5

Installation Instructions
NOTE: If you need to install
ducts, note
that the total
duct length of 3¼"x 10" rectangular or 6" diameter
round duct should not exceed 140 equivalent feet.
Outside ventilation requires a HOOD EXHAUST DUCT.
Read the following careflflly.
NOTE: It is important that venting be installed using
the most direct route and with as few elbows as possible.
This ensures clear venting of exhaust and helps prevent
blockages. Mso, make sure dampers swing freely and
nothing is blocking the ducts.
Exhaust connection:
The hood exhaust has been designed to mate with
a standard 3¼" x 10" rectangular duct.
If a round duct is required, a rectangular-to-round
uansition adaptor must be used. Do not use less than
a 6" diameter duct.
Maximum duct length:
For satisfactory air movement, the total duct length of
3¼"x 10"
rectangular
or 6" diameter round duct should
not exceed 140 equivalent feet.
Elbows, transitions, wall and roof caps,
etc.,
present additional resistance to airflow and are
equivalent to a section of suaight duct which is longer
than their actual physical size. When calculating the total
duct length, add the equivalent lengths of all uansifions
and adaptors plus the length of all suaight duct sections.
The chart below shows you how to calculate total
equivalent ducrwork length using the approximate feet
of equivalent length of some typical ducts.
DUCT PIECES
%
G
O
O
Rectangular-to-Round
TransitionAdapto¢
Wall Cap
%0 Elbow
45° Elbow
%0 Elbow
45° Elbow
RoofCap
Straight Duct6" Roundor
3%" x 10" Rectangular
EQUIVALENT
LENGTH
5 Ft.
40 Ft.
10 Ft.
5 Ft.
25 Ft.
5 Ft.
24 Ft.
1 Ft.
* IMPORTANT: If a rectangular-to-round transition
adaptor is used, the bottom corners of the damper
will hme to be cut to fit, using the tin snips, in
order to allow fi'ee movement of the damper.
NUMBER
x USED
x ( )
x ( )
x ( )
x ( )
x ( )
x ( )
x ( )
x ( )
Total Ductw0rk
EQUIVALENT
=
LENGTH
=
=
=
=
=
=
=
=
==
Equivalent lengths of duct pieces are based on actual tests
and reflect requirements tot good venting pertormance with
any vent hood.
5
Ft.
Ft.
Ft.
Ft.
Ft.
Ft.
Ft.
Ft.
Ft.