Lennox Hearth T300P - Manual (Page 10)

INSTALLATION
PAGE 10
VENTING REQUIREMENTS
It is recommended that only an authorized dealer install
your pellet stove. The specified installation requirements
must be followed to ensure conformity with both the
safety listing of the appliance and local building codes. All
clearances, installation instructions and precautions
specified by the vent manufacturer must be followed.
Selecting a Location - Review the appliance clearance
requirements before installing the venting system (see
Clearances, page 6). Position the appliance far enough
away from walls to allow adequate room for servicing.
Choose the appliance location with the least amount of
interference with the house framing, plumbing, wiring,
etc.
Preferred Vent Configuration – For the best perform-
ance, we recommend a vent run design which runs verti-
cally and terminates above the roofline. This design will
allow natural draft to improve the flow of flue gases and
will aid in combustion and stove performance.
Type of Pipe – This stove requires type “PL” (pellet vent
pipe, sometimes referred to as “L-Vent pellet vent”),
which conforms to UL standard 641. Connect the pellet
vent pipe or the “tee” to the flue collar using a minimum of
three screws and seal as specified in “Pipe Joint Re-
quirements” on this page. Do not use class B gas chimney
or single wall chimney as a substitute.
Size of Pipe -These pellet appliances are approved for
use with the following vent sizes: 3” (75mm) standard, or
4” (100mm). See page 12 for determining correct size
vent to use. Use a 3” (75mm) to 4” (100mm) adapter
(Cat. No. 14M81) or a 3” (75mm) to 4” (100mm) “tee” in
order to run 4” (100mm) pipe.
Offsets - In every installation, a single or double clean-
out “tee” is recommended for every ninety-degree offset
(this tee will help collect ash residue and will allow for
routine cleaning without the need to disconnect sections
of pipe).
Note: Offsets and horizontal runs accumulate fly ash and
soot which reduces the exhaust flow and performance of
the stove.
Total Offsets in venting system should not exceed 270
°
total in direction change.
Horizontal Runs - The maximum total horizontal run
must not exceed 10 feet (3.1 meters).
Horizontal run of pipe requires 1/4” / 7 mm rise per foot.
Pipe Clearances / Requirements – See pipe manufac-
turers instructions for installation of venting components
and clearances. Follow pipe manufacturers installation
precautions for passing pipe through a combustible wall
or ceiling (i.e. use an approved thimble).
Notes:
All pellet vent pipe requires 3” (75mm) clearance from
outside of pipe unless otherwise specified by vent manu-
facturer.
A support bracket should be installed every 4’ (1.2m) of
pellet vent pipe on the exterior wall of the house unless
otherwise specified by vent manufacturer.
Pipe / Liner Joint Requirements - All pipe joints must
be secured with a minimum of 3 screws. ALL horizontal
joints must be sealed gas tight. Use RTV silicone with a
rating of at least 570
° F (969° C), or Interam to provide a
complete seal at the flue collar and on all joints.
Connection to Masonry Chimney through a Wall - Be
sure to verify the construction of a masonry chimney, as it
may have combustible framing.
The use of single wall flex or rigid 24 gage stainless steel
pipe as a liner is approved.
Connection to an Existing Class A Chimney - A chim-
ney adapter can be used to make the connection from 3”
/ 75mm or 4” / 100mm pellet vent pipe to existing UL
chimney system. Verify with the pipe manufacturer that
your pipe brands will interconnect. The use of single wall
flex or rigid pipe (24 gage stainless steel) as a liner is
approved.
Direct-Vent Installations (Horizontal): On all direct-vent
installations (short, horizontal runs with no vertical pipe);
care should be taken when choosing a location for termi-
nating the vent. It is not recommended to directly vent the
exhaust on the prevailing wind side of the house. It is
recommended that when an appliance is vented directly
through a wall, a minimum of 8’ (2.5M) of vertical pipe
should be installed to create some natural draft. This will
reduce the possibility of smoke or odor entering the
dwelling during appliance shutdown or loss of power.