17
DVB4136 Direct Vent Gas Fireplace
20012322
3 x 90°
Elbows
3 x 90°
Elbows
FP1176
Fig. 28
Maximum three (3) 90° elbows per installation.
• The maximum number of elbow degrees in a system
is 270°. (Fig. 32)
Example:
Elbow 1 = 90°
Elbow 2 = 45°
Elbow 3 = 45°
Elbow 4 = 90°
Total angular variation = 270°
Max 20"
Max 20"
36"
(914mm)
Max.
36"
(914mm)
Max.
FP1177
Fig. 29
Maximum horizontal run with no rise.
7'6"
(2.3m)
A
B
A + B = 17' (Max.)
(5.2m)
FP1178
Fig. 30
Horizontal run reduction.
V584-201
Horizontal Run
2/99 djt
A
10’
(3 m)
7’
(2.1 m)
8’
(2.4 m)
V584-201
B
Fig. 31
Maximum vent run with elbows.
1
2
3
4
1
2
3
4
1 + 2 + 3 + 4 = 270°
FP1180
Fig. 32
Maximum elbow usage.
When installing the appliance as a rear
vent unit, the 90° or 45° Transition Elbow
attached directly to the rear of the unit is
NOT INCLUDED in the following criteria
and calculations, and unless specifically
mentioned should be ignored when calcu-
lating venting layouts.
• The maximum number of 90° elbows per side wall
installation is three (3). (Fig. 27)
• If a 90° elbow is fitted directly on top of the fireplace
flange the maximum horizontal vent run before the
termination or a vertical rise is 36” (914 mm). (Fig.
28)
• If a 90° elbow is used in the horizontal vent run
(level height maintained) the horizontal vent length
is reduced by 36” (914 mm). (Fig. 29, 30) This does
not apply if the 90° elbows are used to increase or
redirect a vertical rise. (Fig. 28)
Example:
According to the vent graph (Page 15) the
maximum horizontal vent length in a system with a 7
¹⁄₂
’
(2.3 m) rise is 20’ (6 m) and if a 90° elbow is required in
the horizontal vent it must be reduced to 17’ (5.2 m).
In Figures 30 & 31, dimension A plus B must not be
greater than 17’ (5.2m)
• The maximum number of 45° elbows permitted per
installation is six (6). These elbows can be installed
in either the vertical or horizontal run.
• For each 45° elbow installed in the horizontal run,
the length of the horizontal run MUST be reduced by
18” (457 mm). This does not apply if the 45° elbows
are installed on the vertical part of the vent system.