EN
W415-3096 / C / 05.03.22
15
venting requirements
2.4 venting application flow chart
10.3
TOP EXIT
Horizontal Termination
Vertical Termination
Vertical rise is equal
to or greater than
the horizontal run
Vertical rise is less
than horizontal run
Vertical rise is equal
to or greater than
the horizontal run
Vertical rise is less
than horizontal run
Horizontal run +
vertical rise to
maximum of
35 feet (10.7m)
Horizontal run +
vertical rise to
maximum of 24.75
feet (7.5m)
Horizontal run +
vertical rise to
maximum of
35 feet (10.7m)
Horizontal run +
vertical rise to
maximum of
35 feet (10.7m)
4.2 times the
vertical rise equal to
or greater than the
horizontal run
3 times the vertical
rise equal to or
greater than the
horizontal run
10.2
REAR EXIT
Horizontal Termination
Vertical Termination
Vertical rise is equal
to or greater than
the horizontal run
Vertical rise is less
than horizontal run
Vertical rise is equal
to or greater than
the horizontal run
Vertical rise is less
than horizontal run
3.5 times the
vertical rise equal to
or greater than the
horizontal run
3 times the vertical
rise equal to or
greater than the
horizontal run
Horizontal run +
vertical rise to
maximum of
40 feet (12m)
Horizontal run +
vertical rise to
maximum of
24.75 feet (7.5m).
Horizontal run +
vertical rise to
maximum of
40 feet (12m)
Horizontal run +
vertical rise to
maximum of
40 feet (12m)
2.5 definitions
11.1
For the following symbols used in the venting calculations and
examples are:
> - greater than
> - equal to or greater than
< - less than
< - equal to or less than
H
T
- total of both horizontal vent lengths (Hr) and offsets (Ho) in feet
H
R
- combined horizontal vent lengths in feet
H
O
- offset factor: .03 (total degrees of offset - 90°*) in feet
H
O
- offset factor: .03 (total degrees of offset - 135°*) in feet
V
T
- combined vertical vent lengths in feet
