GE JVM1500 Series, Installation Instructions Manual

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EQUIVALENT NUMBER EQUIVALENT
DUCT PIECES LENGTH x USED = LENGTH
Rectangular-to-Round 5 Ft. x ( ) = Ft.
Transition Adapter*
Wall Cap 40 Ft. x ( ) = Ft.
90° Elbow 10 Ft. x ( ) = Ft.
45° Elbow 5 Ft. x ( ) = Ft.
90° Elbow 25 Ft. x ( ) = Ft.
45° Elbow 5 Ft. x ( ) = Ft.
Roof Cap 24 Ft. x ( ) = Ft.
Straight Duct 6
″
Round or 1 Ft. x ( ) = Ft.
3 1 ⁄
4
″
x 10
″
Rectangular
Total Ductwork = Ft.
*IMPORTANT: If a rectangular-to-round transition
adapter is used, the bottom corners of the damper
will have to be cut to fit, using the tin snips, in order
to allow free movement of the damper.
Equivalent lengths of duct pieces are based on actual tests and reflect
requirements for good venting performance with any vent hood.
5
NOTE: If you need to install ducts, note that the total
duct length of 3 1 ⁄
4
″
x 10
″
rectangular or 6
″
diameter
round duct should not exceed 120 equivalent feet.
Outside ventilation requires a HOOD EXHAUST DUCT.
Read the following carefully.
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.
Also, make sure dampers swing freely and
nothing is blocking the ducts.
Exhaust connection:
The hood exhaust has been designed to mate with
a standard 3
1 ⁄
4
″
x 10
″
rectangular duct.
If a round duct is required, a rectangular-to-round
transition adapter must be used.
Do not use less than
a 6
″
diameter duct.
Maximum duct length:
For satisfactory air movement, the total duct length of
3
1 ⁄
4
″
x 10
″
rectangular or 6
″
diameter round duct should
not exceed 120 equivalent feet.
Elbows, transitions, wall and roof caps,
etc.,
present additional resistance to airflow and are
equivalent to a section of straight duct which is longer
than their actual physical size. When calculating the total
duct length, add the equivalent lengths of all transitions
and adapters plus the length of all straight duct sections.
The chart below shows you how to calculate total
equivalent ductwork length using the approximate
feet of equivalent length of some typical ducts.
Installation Instructions