21
Venting Routes And Components
A gas appliance must not be connected to a chimney flue serving a
separate solid-fuel burning appliance.
Since it is very important that the vent system maintain its balance
between the combustion air intake and the flue gas exhaust, certain lim-
itations as to vent configurations apply and must be strictly adhered to.
The table showing the relationship between vertical and horizontal side
wall venting will help to determine the various vent lengths.
The maximum horizontal run with the 90 degree bend at the fireplace
flue outlet is 4 ft/122cm (Figure #1). The maximum horizontal run is
20 ft/6.1m when the vertical run is 7 ft/2.1m. (Figure #2). Note: 1/4”
vertical rise is required for every 12” of horizontal run.
The maximum number of 45 degree bends per side wall installation is
two (2) in the horizontal run and then you must reduce the length of the
horizontal by 18 inches for each 45 degree bend.
The maximum vertical run is 40 ft/12.2 meters.
Special Note: For each 45 degree bend installed in the horizontal
run, the length of the horizontal run must be reduced by 18”
(45cm). This does not apply if the 45 degree bends are installed on
the vertical part of the vent system.
Example:
If according to the table, the length of the horizontal run is
10 feet, and two 45 degree bends are required, the horizontal run length
must be reduced to 7 feet.
How To Use The Horizontal Vent Table
1. Determine the height of the system and the number of bends
required.
2. Having determined the vertical distance determine the maximum
horizontal section allowed.
3. Vent table has been established for 90˚ horizontal/vertical runs.
With use of flex pipe distance not having 90˚ bends will not fall into
vent table standards. See Fig. B.
Horizontal Venting Table From Bottom of Fireplace
for venting to a maximum of 40 ft. (12.2 meters)
Total Vertical
Max Total Horizontal
Feet
Meters
Feet Meters
4
1.2
5
1.5
5
1.5
8
2.4
6
1.8
12
3.7
7
2.1
20
6.1
8
2.4
20
6.1
9
2.7
20
6.1
10
3.0
20
6.1
11
3.4
20
6.1
12
3.7
20
6.1
13
4.0
20
6.1
14
4.3
20
6.1
15
4.6
20
6.1
16
4.9
20
6.1
17
5.2
20
6.1
18
5.5
20
6.1
19
5.8
20
6.1
20
6.1
20
6.1
25
7.5
15
4.6
30
9
10
3.0
40
12.2
0
0
Example A:
If the vertical dimension from
the floor of the fireplace is 6ft,
the horizontal run to the wall
flange of the vent termination
must not exceed 12ft.
NOTE: The final location of
the fireplace must be such
that the horizontal vent
dimensions fall within those
stated on the graph. The
Maximum Vertical vent run
is 40ft. (12.2 meters).
Important:
Always locate the fireplace in such a way that a minimum of off-
sets and/or horizontal runs are required. 1/4” vertical rise is required for every
12” horizontal run.
Important:
Minimum clear-
ance between vent pipes and
combustible materials is 1 inch
(25mm).
36"
MINIMUM
12 ft.
6 ft.
SUPPORT STRAP ON 90° BEND
MAX. HORIZONTAL
FIGURE A
FIGURE B
TOT
AL VER
TICAL
It is recommended for
Propane Horizontal Installations
that the
venting should be a minimum of one foot vertical off the flue
before the elbow on any horizontal runs of one foot or greater.
This allows for cleaner combustion and greatly reduces carboning
and cleaning of glass. (Does not apply to Back Flue Models).
2 additional 90 degree bends or equals are allowed. The horizontal
run must be reduced by 36” per each 90 degree bend, or 18” per
each 45 degree bend.
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