26
EXTERNAL EXHAUST DUCTING
OUTSIDE TOP EXHAUST (EXAMPLE ONLY)
The following chart describes an example of one possible ductwork installation.
OUTSIDE BACK EXHAUST (EXAMPLE ONLY)
NOTE: For back exhaust, care should be taken to align exhaust with space between studs,
or wall should be prepared at the time it is constructed by leaving enough space between
the wall studs to accommodate exhaust.
The following chart describes an example of one possible ductwork installation.
EQUIVALENT
NUMBER
EQUIVALENT
H
T
G
N
E
L
=
D
E
S
U
x
H
T
G
N
E
L
S
E
C
E
I
P
T
C
U
D
24 Ft. (7.3 m) x (1) = 24 Ft. (7.3 m)
12 Ft. (3.6 m) x (1) = 12 Ft. (3.6 m)
12 Ft. (3.6 m) Straight
Duct (6”/15.2 cm
Round)
5 Ft. (1.5 m) x (1) = 5 Ft. (1.5 m)
Rectangular-to-Round
Transition Adaptor*
Equivalent lengths of duct pieces are based on actual tests and
* 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.
reflect requirements for good venting performance with any vent hood.
Total Length =
41 Ft. (12.5 m)
Roof Cap
Wall Cap
40 Ft. (12.2 m) x (1) =
3 Ft. (0.9 m) x (1) =
10 Ft. (3 m) x (2) =
40 Ft. (12.2 m)
3 Ft. (0.9 m)
20 Ft. (3 m)
90° Elbow
3 Ft. Straight Duct
(31/4” x 10”/8.2 x 25.4 cm
Rectangular)
EQUIVALENT
NUMBER
EQUIVALENT
H
T
G
N
E
L
=
D
E
S
U
x
*
H
T
G
N
E
L
S
E
C
E
I
P
T
C
U
D
Equivalent lengths of duct pieces are based on actual tests and
reflect requirements for good venting performance with any vent hood.
Total Length =
63 Ft. (19.2 m)
