10
XXV Pellet Stove
3-90-00885R17_02/15
Outside air flex
pipe goes here.
Inlet Cover part#
1-10-09542
venting
Fig. 7
Fig. 8
Outdoor Half
Indoor Half
Adjustable from 4 1/2" to 10 5/8"
wall thickness
Avoiding Smoke and Odors
Negative Pressure, Shut-down, and Power Failure:
T
o reduce the probability of back-drafting or burn-back in
the pellet burning appliance during power failure or shut-
down conditions, the stove must be able to draft naturally
without exhaust blower operation. Negative pressure in the
house will resist this natural draft if not accounted for in the
pellet appliance installation.
Heat rises in the house and leaks out at upper levels. This
air must be replaced with cold air from outdoors, which flows
into lower levels of the house. Vents and chimneys into
basements and lower levels of the house can become the
conduit for air supply, and reverse under these conditions.
Outside Air:
Hearth & Home Technologies strongly recommend
attaching outside air in all installations, especially lower
level and main floor locations.
Per national building codes, consideration must be given to
combustion air supply to all combustion appliances. Failure
to supply adequate combustion air for all appliance demands,
may lead to back-drafting of those and other appliances.
When the appliance is side-wall vented: The air intake is best
located on the same exterior wall as the exhaust vent outlet
and located lower on the wall than the exhaust vent outlet.
When the appliance is roof vented: The air intake is best
located on the exterior wall oriented towards the prevailing
wind direction during the heating season.
The outside air connection will supply the demands of the
pellet appliance, but consideration must be given to the
total house demand. House demand may consume some
air needed for the stove, especially during a power failure. It
may be necessary to add additional ventilation to the space in
which the pellet appliance is located. Consult with your local
HVAC professional to determine the ventilation demands for
your house.
There is a break-away hole on the rear panel of the stove
which must be removed to connect the flex pipe. The
maximum length run of this pipe is 15 feet. If a longer run
is needed the size must be increased to 3". Inlet cover part
number 1-10-09542 should be used to keep birds, rodents,
etc.out of the pipe unless the Harman® wall passthrough is
being used.
direct vent wall Passthrough
The Harman® Direct Vent Wall Passthrough (Part # 1-00-
677177) makes installing your Harman® Pellet Stove with
outside air easier. It combines the needed wall protection
for the venting, with a source of intake air for combustion. It
is made to fit walls from 4 1/2" to 10 1/8" thick with a single
square opening in the wall of 6-1/2 inches.
Canadian Standard, ULC-S627-00 Requires that all
outdoor-aired appliances must be secured to the
structure.
