Hearth & Home Technologies MTVERNINSAE-MBK Manuel D’Utilisation

Page de 52
Page  14
7036-135E
September 1, 2008
R
Mt. Vernon Pellet Insert (AE)
D. Pipe Selection Chart
Fire Risk.
Do NOT pack insulation or other 
combustibles between firestops.
•  ALWAYS maintain specified clearances 
around venting and firestop systems.
•  Install firestops as specified.
Failure to keep insulation or other material 
away from vent pipe may cause fire.
WARNING
The chart will help you in determining proper venting size 
according to the equivalent feet of pipe calculated in the Vent 
Termination Calculaltion Table and the altitude above sea 
level of this installation.  See Figure 14.1.
Locate the calculated equivalent feet of pipe on the vertical 
left side of the chart.  Move to the right horizontally on the 
chart until you reach your altitude above sea level.
If you fall below the diagonal line, 3 or 4 inch (76 to 102mm) 
pipe may be used.  If it is anywhere above the diagonal line, 
a 4 inch (102mm) diameter pipe is required.
The chart reveals that a 90° elbow is 5 times as restrictive 
to the flow of exhaust gases under positive pressure as one 
foot of horizontal pipe, and a foot of horizontal pipe is twice 
as restrictive as a foot of vertical pipe.
Figure 14.1
3 in. or 4 in. (76mm or 102mm) Diameter  Pipe 
Equivalent Pipe 
Length In Feet
ALTITUDE IN THOUSANDS OF FEET 
0
20
30
   1        2       3       4       5       6        7       8        9     10
4 in. (102mm) Diameter Pipe Only 
10
Example 1
Example 2
Example 1:  If the equivalent length of pipe is 23 feet with altitude of 
8,000 feet you must use 4 inch (102mm) diameter type “L” or “PL” 
vent.
Example 2:  If the equivalent length of pipe is 12 feet with altitude of 
6,000 feet you may use 3 or 4 inch (76 to 102mm) diameter type “L” 
or “PL” vent