Installation Guide
EQUIVA
LENT
NUMBER EQUIVA
LENT
DUCT PIECES LENGTH x USED = LENGTH
5 Ft. (1.5 m)
x ( ) =
Ft. or mRectangular-to-Round
Transition Adaptor*
Wall Cap 40 Ft. (12.2 m)
x ( ) =
Ft. or m
90° Elbow 10 Ft. (3 m)
x ( ) =
Ft. or m
45° Elbow 5 Ft. (1.5 m)
x ( ) =
Ft. or m
90° Elbow 25 Ft. (7.6 m)
x ( ) =
Ft. or m
45° Elbow 5 Ft. (1.5 m)
x ( ) =
Ft. or m
Roof Cap 24 Ft. (7.3 m)
x ( ) =
Ft. or m
1 Ft. (0.3 m)
x ( ) =
Ft. or m
(8.2 x 25.4 cm Rectangular)
Total Ductwork = Ft. or m
Equivalent lengths of duct pieces are based on
actual tests and reflect requirements for good
venting performance with any vent hood.
* IMPORTANT : If 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
.
Installation Instructions
IN
STA
LLATION INSTRUCTIONS FOR EXTERNAL EXHAUST DUCTING
EN-14
Maximum duct length:
F
o
r
s
a
t
isfactory air movement, the total duct length of
3
1
⁄4"
x 10"
(8.2 x 25.4 cm) rectangular or
e
x
ceed
14
0 e
quiv
a
lent feet (42.7 m).
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.
diameter/
6"
(15.2 cm)
diameter round duct should not
5"
(12.7 cm)
NOTE: If you need to install ducts, note that the total duct
length of 3
1
⁄4"
x 10" (8.2 x 25.4 cm) rectangular or
5" (12.7 cm)diameter/6" (15.2 cm) diameter round duct
should not exceed 140 equivalent feet (42.7 m).
Outside ventilation requires an EXTERNAL 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 exhaust adaptor has been designed to mate with a
standard 3
1
⁄4"
x 10" (8.2 x 25.4 cm) rectangular duct.
If a round duct is required, a rectangular-to-round
tr
ansition adaptor must be used. A 5" (12.7cm)/ 6" (15.2cm)
diameter duct is acceptable to use.
Straight Duct 6" (15.2 cm)
Round or 3
1
⁄4"
x 10"