Figure 5
Horizontal rear termination
See figure 5.
Can be used with either #551DVK standard vent kit or #984
Dura-vent terminal cap and accessories.
Adapter #817VAK, one 90° vent elbow #990B and Dura-vent
pipe lengths will be required.
(See venting options section of this manual).
The location requirements are shown in the table and graph
below and figure 5.
(See page 16 graph 2 for restrictor installation detail)
Graph 1
Minimum Maximum
A
: From floor to top of
vent duct
3ft 7
9
/
16
”
(111cm)
9ft 1
9
/
16
”
(278cm)
B
: Frame front face to
outside wall
- 17ft
4”
(528cm)
C
: Frame front face to
inside wall
16”
(40.6cm)
-
D
: Vertical pipe run
between vent adaptor
and elbow
6”
(152mm)
6ft
(183cm)
E
: Horizontal pipe run
(including terminal
pipe) from elbow.
- 16ft
(488cm) with
no elbows in
horizontal run
F
: Clearance to
combustible materials
above horizontal pipe
run inside building
(Outside wall
shields/thimbles)
5”
(12.7cm)
-
G
: Clearance to
combustible materials
below horizontal pipe
run
1
5
/
16
”
(3.3cm)
-
H
: Clearance to
combustible materials
all round vertical pipe
run and at sides of
horizontal pipe run
2”
(5.1cm)
-
For installations with a horizontal rear termination, the
combination of horizontal and vertical vent pipes must be
within the allowed area shown in Graph 1. A minimum
vertical pipe run of 6” is necessary.
Example a: If a vertical rise of 2ft 3” is required, the
horizontal run must not be more than 11ft 6”.
Example b: If a horizontal run of 3ft 6” is required, the
vertical run must be at least 1ft 3”.
The horizontal vent pipe run may be
redirected by using elbows up to a total of
180º but the maximum horizontal run (E in
figure 5 & graph 1) is reduced by 18” for
every 45º. For example if two 90º elbows are used
as in figure 5a the maximum horizontal run is
reduced by 3ft per elbow –
Total reduction = 6ft.
Figure 5a
7 of 23
