11
Heat & Glo • TIARA II-B • 7011-148 Rev. G • 10/12
D.
How to Use the Vent Graph
E.
Venting Guidelines
1. Measure the distance from the top of appliance 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 16 ft.
(5m).
.
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 12 ft. 10 in. (4m).
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 20 ft. (6m) 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.; 20 ft.
max. - 6 ft. = 14 ft. max.).
• The maximum horizontal vent run is 20 ft. (6m) when the
vertical vent rise is 10 ft. (3m).
• The minimum horizontal vent run is 6 in. (152mm).
• Horizontal sections require a 1/4 in. (6mm) rise for every 12
in. (305 mm) of horizontal travel.
• Exterior Vent Diameter = 6-5/8 in. (168mm); Inner Vent
Diameter = 4 in. (102mm).
• Horizontal sections require non-combustible support every
3 ft. (914mm), e.g. wall straps.
• For any vertical termination a minimum of 6 ft. (2m) vertical
must be used.
Figure 5.2
Example 1
Example 2
2' 4' 6 ' 8' 10' 12' 14' 15' 16' 17' 18' 19' 20'
2'
4'
6'
8'
10'
12
'
14'
16'
18'
20'
22'
24'
26'
28'
30'
32'
34'
35'
36'
37'
38'
39'
40'
Damper position
more CLOSED in
this area
C
L
40 ft. (12m)
Maximum Vertical
VERTICAL DISTANCE
FROM APPLIANCE TO
90° ELBOW
6 in. (152mm) Minimum
Vertical Termination
For rear vent or top of
appliance for top vent
C
L
6 in. (152mm) Minimum starter pipe
3 ft. (914mm) Maximum Horizontal run with no
vertical pipe and with 1/4 in (6mm) rise per foot.
Must use Snorkel cap.
No damper
in this area
Damper position
more OPEN in
this area
Part: SLK-991DA
Part: SLK-011TRD
EXCEPTIONS FOR HORIZONTAL INSTALLATIONS:
*When installing in a rear vent configuration with no
vertical rise, a Snorkel Kit must be used. Refer to venting
components.
*The maximum horizontal vent run is 3 ft. (914mm).
*The maximum horizontal vent run with a 45° elbow is 2 ft.
(609mm).
*The minimum horizontal vent run is 6 in. (152mm).
INDIVIDUAL INSTALLATIONS MAY VARY. PERCENTAGE
CLOSED BASED ON FULL RANGE OF DAMPER TRAVEL.
NOTE: IF YOUR INSTALLATION FALLS WITHIN A SHADED
AREA ON THE GRAPH, THE DAMPER MUST BE USED.* SEE
INFORMATION ON DAMPER ADJUSTMENT ON PAGE 31.
*In the Commonwealth of Massachusetts, the word damper
shall be replaced with the words flue restrictor.
