EQUIVALENT NUMBER
EQUIVALENT
DUCT PIECES
LENGTH
x
USED
=
LENGTH
Roof Cap
24 Ft. (7.3 m)
x
(1)
=
24 Ft. (7.3 m)
12 Ft. (3.6 m) Straight Duct 12 Ft. (3.6 m)
x
(1)
=
12 Ft. (3.6 m)
(6”/15.2 cm Round)
Rectangular-to-Round
5 Ft. (1.5 m)
x
(1)
=
5 Ft. (1.5 m)
Transition Adaptor*
Equivalent lengths of duct pieces are based on actual tests and
reflect requirements for good venting performance with any vent hood.
Total Length
=
41 Ft. (12.5 m)
The following chart describes an example of one possible
ductwork installation.
NOTE: Read these next two pages only if you plan to vent your exhaust to the
outside. If you plan to recirculate the air back into the room, proceed to page 20.
OUTSIDE TOP 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.
* 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.
The following chart describes an example of one possible
ductwork installation.
Installation Instructions
OUTSIDE BACK EXHAUST (EXAMPLE ONLY)
EQUIVALENT NUMBER
EQUIVALENT
DUCT PIECES
LENGTH*
x
USED
=
LENGTH
Wall Cap
40 Ft. (12.2 m)
x
(1)
=
40 Ft. (12.2 m)
3 Ft. Straight Duct
3 Ft. (0.9 m)
x
(1)
=
3 Ft. (0.9 m)
(3
1
⁄
4
” x 10”/8.2 x 25.4 cm
Rectangular)
90° Elbow
10 Ft. (3 m)
x
(2)
=
20 Ft. (3 m)
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)
EXTERNAL EXHAUST DUCTING
11
