12
BDVT Series Direct Vent Gas Fireplace
10003358
20’ (6m)
7.5’ (2.3m)
Pipe Straps
Every 3’ (914mm)
Firestop/Zero
Clearance Sleeve
Pipe
Straps Every
3’ (914mm)
FP1012
Fig. 13 Support straps for horizontal runs.
•
If a 90
°
elbow is used in the horizontal vent run
(level height maintained) the maximum horizontal
vent length is reduced by 36” (914mm). This does
not apply if the 90
°
elbows are used to increase or
redirect a vertical rise.
Example: According to the chart the maximum
horizontal vent length in a system with a 7.5’ (2.3m)
vertical rise is 20’ (6m) and if a 90
°
is required in
the horizontal vent it must be reduced to 17’ (5.2m).
In Figure 15, Dimension A plus B must not be
greater than 17’ (5.2m).
Since it is very important that the venting
system maintain its balance between the
combustion air intake and the flue gas
exhaust, certain limitations as to vent
configurations apply and must be strictly
adhered to.
The vent graph showing the relationship between
vertical and horizontal side wall venting will help to
determine the various dimensions allowable.
Minimum clearance between vent pipes
and combustible materials is one 1”
(25mm) on top, bottom and sides unless
otherwise noted.
When the vent termination exits through foundations
less than 20” (508mm) below siding outcrop, the vent
pipe must flush up with the siding.
It is always best to locate the fireplace in such a way
that minimizes the number of offsets and horizontal
vent length of vent pipe from the flue collar of the
fireplace to the face of the outer wall.
Vertical Sidewall Applications
How to Use the Vent Graph
The vent chart should be read in conjunction with the
following vent installation instructions to determine the
relationship of the vertical and horizontal dimensions of
the vent system.
1. Determine the height of the center of the horizontal
vent pipe exiting through the outer wall. Using this
dimension on the Sidewall Vent Graph (Fig. 12),
locate the point intersecting with the slanted graph
line.
2. From the point of this intersection, draw a vertical
line to the bottom of the graph.
3. Select the indicated dimension, and position the
fireplace in accordance with same.
Example A:
If the vertical dimension from the floor of the fireplace
is 11’ (3.4m) the horizontal run to the face of the outer
wall must not exceed 14’ (4.3m).
Example B:
If the vertical dimension from the floor of the unit is 7’
(2.14m), the horizontal run to the face of the outer wall
must not exceed 8
¹⁄₂
’ (2.6m).
Horizontal dimension from the outside face of the wall to
the center of the fireplace vent flange
Sidewall vent graph showing the relationship between vertical
and horizontal dimensions for a Direct Vent flue system.
Vertical dimension from the floor of the fireplace to
the center of the horizontal vent pipe
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
eg: A
eg: B
Fig. 12 Sidewall venting graph. (Dimensions in feet)
Horizontal plane means no vertical rise exists on this
portion of the vent assembly.
•
The maximum number of 90
°
elbows per side wall
installations is three (3).
•
If a 90
°
elbow is fitted directly onto the fireplace
flange the maximum horizontal vent run before the
termination or a vertical rise is 36” (914mm).
