10/08
Page 11
Quadra-Fire • Columbia Bay • 250-5195 Rev. K
D.
How to Use the Vent Graph
E.
Venting Guidelines
Figure 5.2
NOTES
The maximum horizontal vent run is 15 ft. (5m) when the
vertical vent rise is 10 ft. (3m).
The minimum horizontal vent run is 11 in. (279mm).
Horizontal sections require a 1/4 in. (6mm) rise for every 12
ft. (305mm) of horizontal travel.
Exterior Vent Diameter = 6 5/8 in. (168mm); Inner Vent Diam-
eter = 4 in. (101mm)
Horizontal sections require noncombustible support every 3
ft. (914mm), e.g. wall straps.
A minimum 2 ft. (610mm) vertical rise is required before the
90 degree elbow.
1. Measure the vertical distance from the center line of the
flue pipe to the center of the 90° elbow. On the graph
below, draw a horizontal line from that measurement
on the vertical axis across until it intersects with the
slanted line.
2. From the point of this intersection, draw a vertical line to
the bottom of the graph.
3. The point at which this line meets the bottom line of the
graph is the maximum length of the horizontal run.
EXAMPLE 1:
If the vertical dimension from the center line
of the fl ue vent to the center of the 90° elbow is 7 ft. (2m),
the horizontal run to the outer wall fl ange must not exceed
13 ft. (4m).
EXAMPLE 2:
If the vertical dimension from the center line
of the fl ue vent is 21 ft. (6m), the horizontal run to the outer
wall fl ange must not exceed 9 ft. (3m).
4. Each 90° elbow is equivalent to 3 ft. (914mm) of vent
pipe and each 45° elbow is equivalent to 1 ft. (305mm)
of vent pipe, and must be subtracted from the vent pipe
run. A single horizontal to vertical 90° elbow is already
calculated into the allowable 15 ft. (5m) run. Each
additional 90° elbow reduces the maximum horizontal
distance by 3 ft. (914mm).
EXAMPLE:
The use of 3 elbows would reduce the allowable
horizontal run to 9 ft. (3 -1 = 2 elbows x 3 ft. = 6 ft.; 15 ft.
max. - 6 ft. = 9 ft. maximum).
NOTE:
If your installation falls within the gray-shaded area
on graph, see information on Vertical damper adjustment in
Section 8. (In the Commonwealth of Massachusetts, the word
damper shall be replaced with the words flue restrictor.)
VERTICAL DISTANCE
FROM APPLIANCE TO
TO THE 90° ELBOW
EX. 2
EX. 1
11" 2' 4' 6' 8' 10' 12' 14' 15'
30'
28'
26'
24'
22'
20'
18'
16'
14'
12'
10'
8'
6'
4'
2'
0'
(MAX)
(MIN)
32'
34'
35'
TOTAL HORIZONTAL RUN TO OUTSIDE OF
EXTERIOR WALL (INCLUDING ELBOWS)
