6
31-7000069 Rev. 1
EQUIVALENT
NUMBER
DUCT PIECES
LENGTH
x
USED
=
LENGTH
Rectangular-to-Round
5
Ft.
x (
)
= Ft.
Transition
Adaptor*
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.
Ü÷õäìêë÷Íøæ÷&ėÛòøñçòõ
!Ï÷
û
¤¥
Ï÷
3
1
\
4
ėû! ėÛèæ÷äñêøïäõ
Total
Ductwork
= Ft.
Equivalent lengths of duct pieces are based on actual tests
and reflect requirements for good venting performance with
any vent hood.
*
IMPORTANT: I
f a rectangular-to-round transition
adaptor 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.
NOTE:
If you need to install ducts, note that the total duct
length of 3
1
\
4
ėû! ėõèæ÷äñêøïäõòõ&ėçìäðè÷èõõòøñççøæ÷
should not exceed 140 equivalent feet.
Øø÷öìçèùèñ÷ìïä÷ìòñõèôøìõèöäÑØØÍÎáÑÊÞÜÝÍÞÌÝ
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
ėû! ėõèæ÷äñêøïäõçøæ÷
If a round duct is required, a rectangular-to-round
transition adaptor must be used.
Do not use less than
a 6
ė
diameter duct.
Maximum duct length:
For satisfactory air movement, the total duct length of
3
1
\
4
ėû! ėõèæ÷äñêøïäõòõ&ėçìäðè÷èõõòøñççøæ÷
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 straight duct which is longer than their
actual physical size. When calculating the total duct
length, add the equivalent lengths of all transitions and
adaptors 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