Venting – Harman Stove Company The Harman Accentra Pellet Insert User Manual
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A combustion blower is used to extract the com-
bustion gases from the firebox. This causes a negative
pressure in the firebox and a positive pressure in the
venting system as shown in fig. 46. The longer the vent
pipe and more elbows used in the system, the greater
the flow resistance.
The recommended maximum flue lengths for the
Accentra Insert are as follows:
4" Stainless Steel Flex: 30 Lineal ft. Vertical*
4" PL Vent Pipe:
4" Pl Vent Pipe: 30 Lineal ft. Vertical*
4" Pl Vent Pipe: 14 ft. Vertical w/1-90
o
and 12 lineal ft. horizontal*
If additional 4" PL Vent fittings are required, the overall
length must be reduced by:
Vertical 90
o
or T:
2.5'
Vertical 45
o
:
1.5'
Horizontal 90
o
or T: 5.0'
Horizontal 45
o
:
2.5'
3" PL Vent Pipe:
20 Lineal ft. vertical*
8 Lineal ft. vertical w/1-90
o
& 8 lineal ft. horizontal*
If additional 3" PL Vent fittings are required, the overall
length must be reduced by:
Vertical 90
o
or T:
2.0'
Vertical 45
o
:
1.0'
Horizontal 90
o
or T: 4.0'
Horizontal 45
o
:
2.0'
* Long runs of flex or PL vent pipe installed directly vertical from the flue stub
may require more frequent cleaning due to fly ash falling off inside and
collecting directly above the combustion blower outlet.
Any use of horizontal venting will require more frequent cleaning. It is the
responsibility of the installer to make sure all flue configuration are accessible
for cleaning.
4" stainless steel flex vent piping is only allowed
for use in masonry fireplaces and chimneys or factory
built wood burning fireplaces with class A metal chim-
neys. All pellet vent pipe whether flex type, PL or an-
other approved type must be secured together either
by means provided by pipe manufacturer or by 3 screws
at each joint.
D O NOT IN STA LL A FLUE D AMPER IN TH E
EXHAUST VENTING SYSTEM OF THIS UNIT.
DO NOT CONNECT THIS UNIT TO A CHIMNEY
FLUE SERVING ANOTHER APPLAINCE.
Venting
+ = Positive static pressure
= Negative static pressure
Fig.46
Inside hopper
Inside
firebox
In flue pipe
In fan
chamber
&
starter
collar