Harman PB 105, Installation & Operating Manual, Page: 11 / 40

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The minimum vent configuration is a 90
o
or Tee on
a starter collar and a 24” length horizontal through an
exterior wall. A cap on the end should direct the flue
gasses down and away from the structure. See Fig. 5.
The maximum horizontal length is 18 feet. The
minimum termination height above the exterior grade
is 18”. The maximum total length of any configuration
is 30 feet*.
* ( see venting graph on page 10 for exceptions )
NOTE: Cleanout Tee’s should always be used on the
transitions to horizontal pipe to allow easy access for
cleaning.
The venting graph allows for one(1) 90 deg. or Tee
fitting in any configuration.
If more 90’s, T’s, or 45’s are needed the total length
must be adjusted to allow for the added restriction.
Up to four (4) additional 90’s, Tee’s, or equivalent 45’s
can be added as long as the overall length is adjusted in
accordance with the values listed below.
( See the venting graph on page 10.)
Each Vertical ---- 90 deg. or T subtract 2.5 feet
Each Vertical ---- 45 deg. subtract 1.5 feet
Each Horizontal - 90 deg. or T subtract 5.0 feet
Each Horizontal - 45 deg. subtract 2.5 feet
Any exterior venting (vent pipe exposed to outside
ambiant temperatures) should be kept to a minimum,
due to potential condensation problems.
This is especially important in high humidity cold
weather climates, such as maritime areas, lake shores,
and low river valleys.
Venting
venting
4” Type “L” or
“PL” Vent pipe
This is the minimum venting configuration.
Fig. 5
Venting
Use 4” pellet vent pipe to vent your PB105.
A combustion blower is used to extract the combustion
gases from the firebox. This creates a negative pressure in
the firebox and a positive pressure in the venting system
as shown in Fig. 4. The longer the vent pipe and more
elbows used in the system, the greater the flow resistance.
Because of these facts we recommend using as few elbows
as possible and 30 feet or less of vent pipe. The maximum
horizontal run should not exceed 18 feet.
Be sure to use wall and ceiling pass through fittings
(which are approved for pellet vent pipe ) when going
through combustible materials. Be sure to use a start-
ing collar to attach the venting system to the stove. The
starting collar must be sealed to the stove flue collar
with high temp silicone caulking or aluminum tape,
and screwed into the stove flue collar at least three (3)
places.
-
Fig. 4
+
Vent Pipe
4” pellet vent pipe (also known as “L or PL” vent) is
constructed of two layers with air space between the layers.
This air space acts as an insulator and reduces the outside
surface temperature to allow a minimum clearance to com-
bustibles of 1 inch. In Canada the minimum clearance to
combustibles is 3 inches.
The sections of pipe lock together to form an air tight
seal in most cases; however, in some cases a perfect seal
is not achieved. For this reason and the fact that the PB105
operates with a positive vent pressure,
we specify that all
joints within the structure should also be sealed with
clear silicone.
NOTE:Use only 4” diameter type “L” or “PL” venting
system. Be sure to inspect and clean exhaust venting
system frequently.