The harman Accentra Pellet Insert

& Operating
& Maintenance
The Harman Accentra Pellet Insert
“Ce manuel est disponible en Français sur demande”
Please read this entire manual before you install and use your new room heater. Failure
to follow instructions may result in property damage, bodily injury, or even death.
INSTALLATION DIRECTIONS. do not use makeshift compromises.
Contact your local authority (such as municipal building department, fire department, fire
prevention bureau, etc.) to determine the need for a permit.
Cette guide d'utilisation est disponible en francais. Chez votre concessionnaire de
save these instructions.
Item# 3-90-00674
Maintenance - Cleaning Glass on View Door
The glass used in your stove is manufactured to exact standards to withstand the high heat of the fire, but
like all glass, it must be treated with common sense and care. Never abuse the glass by slamming the door
shut or striking the glass with a heavy object. If the glass is broken or damaged, do not operate the stove until
it has been replaced.
Glass - Replacement
If the stove’s glass is cracked or broken, you must replace it before operating your stove. Remove pieces
carefully. Replace glass only with Harman replacement glass; do not use substitutes.
Carefully remove damaged glass, gasket material, and hold down clips (set aside).
Install the self adhesive 1/4"” gasket material around the front face of the glass. Set the glass panel and gasket
gently onto the door. Install the hold down clips and tighten with bolts.
Glass - Cleaning
Sometimes it will be necessary to clean accumulated ash from the glass surface; allowing this ash to remain
on the glass for long periods can result in “etching” due to the acidity of the ash. Never clean the glass while it
is hot, and do not use abrasive substances. Wash the surface with cool water, and rinse thoroughly. You may
wish to use a non-abrasive cleaner specifically designed for use on stove glass. In any case, dry thoroughly
before relighting your stove.
Disposal of ashes: Ashes should be placed in a metal container with a tight fitting lid. The closed container of
ashes should be placed on a non-combustible floor or on the ground, well away from all combustible materials,
pending final disposal. If the ashes are disposed of by burial in soil or otherwise locally dispersed, they should
be retained in the closed container until all cinders have thoroughly cooled.
Soot and fly ash: Formation and need for removal. The products of combustion contain small particles of
fly ash. The fly ash will collect in the exhaust venting system and will restrict the flow of the flue gases. Pellet
fuels have different ash contents depending on what type of wood has been used to make the pellets. We
recommend to clean the system after approximately 1 ton of pellets have been burned and judge from
that how often the stove should be cleaned, remember if you change pellets it may change how often
you have to clean your stove.
When burning wood slowly, the potential exists for creosote to form. The venting system should be
inspected periodically throughout the heating season to determine if a creosote buildup has occurred. If a
significant layer of creosote has accumulated (3mm or more), it should be removed to reduce the risk of
a chimney fire. If a fire occurs, call the fire department, shut down the stove, and evacuate the residence.
Before using the appliance, have the venting system thoroughly inspected and replace any damaged
Replace glass
only with high
ceramic glass.
Glass Gasket
Fig. 57
Inspect door gasket during
cleaning and inspection
Maintenance - Burn Pot
Burn Pot Cleaning and Maintenance
Whenever adding fuel, take the opportunity to clean
the burn pot.(Weekly at minimum)
• Scrape the top holed surface and sides of the burn
pot down to auger tube.(Fig 58) It is not necessary to
completely remove all material from the burn pot. The
excess will be pushed out during the next use.
Monthly, or after each ton of fuel burned:
• Loosen the (2) wing thumb screws on the lower front
angle of the burn pot. (Fig. 59)
• Lift off the clean-out cover (Fig.59) to open the
bottom clean-out chamber. (Fig.60)
Disconnect the power to the unit before
removing cover.
Fig. 59
Burn pot igniter
• Clean ash buildup from inside the chamber while
cover is off. Use the scraper to tap on the top front
edge of the burn pot. This will help knock pieces of
ash, loosened by the scraping process, down through
the holes. It also helps knock scale off of the igniter
Figure 60
The igniter is made to be removable for service
by insulated male/female wire connectors. These
connections between the hot leads (the wires inside
the burn pot) and the cold leads (the wires from the
control board) are always pulled to the inside rear of
the feeder body. (Not coiled inside the burn pot.)
It is very important that these connections are to the
inside rear of the feeder body. Also, the extra wire of
the igniter wire service loop must be pulled out through
the rear of the feeder and tied up so that it will not be
damaged by any moving parts.
Use caution when cleaning burn pot clean-out
chamber. Do not damage the high temperature
igniter wires.
Igniter hot lead wires
(high temperature)
Fig. 60
Viewed from below through the ash pan opening.
Note: The hot lead/cold lead connection
must always be pulled to the rear of the
feeder body before operation.
Maintenance - Cleaning
Monthly Cleaning- continued:
There is a 2" square exhaust tube on each side (lower
left and right corners) of the firebox. They can only be
seen with the cast heat exchanger covers removed.
Fig. 61
Cleaning the Heat Exchanger tubes
Using the cleaning brush provided, clean these tubes
after every 1 ton of pellets are used.
These tubes are an important part of the heat exchanger. Efficiency will be lost if they are not properly
maintained. The right side tube is a straight passage
to the combustion blower chamber. The Left side tube
follows straight back then makes a right turn, across
the back, to the combustion chamber. You will need
to use the entire length of the cleaning brush handle
to properly clean this tube.
Fig. 62
Primary Air Inlets
Fig. 63
Cleaning the Heat Exchanger
The accordion heat exchanger surfaces are the primary
source of heat transfer into the room. Therefore, it is
very important to keep them clean from flyash and
soot buildup.
• The heat exchanger surfaces should be cleaned after
approximately every 1 ton of pellets are used.
• Use the scraper provided to clean all the way into
the point.
• Note: An old paint brush works well to clean these
• Note: The unit “must be cold” before using anything
other than a wire brush.
• There are 2 primary air inlet holes on the rear flange
of the burnpot. They should be checked for blockage
and cleaned with a vacuum if necessary. Note: The
bottom of the flame guide has 2 notches that match
the holes.
Maintenance - Cleaning
Feeder Chamber
Feeder rear
clean out
wing nut
Fig. 64
slide plate
Possible pellet
fines buildup
This chamber may get a buildup of fines from the feeder
mechanism movement. This area should be checked and
cleaned at least once a year.
To remove the feeder cover:
• Remove the 5/16" wing nut.
• Slide the cover off of the threaded stud.
• Inspect and clean the inner chamber if necessary. See
Fig. 65.
• Reinstall the cover making certain it is centered on the
feeder body and tighten as tightly as you can by hand.
The combustion blower is made to be removed easily for
inspection and cleaning. See Fig. 67.
The combustion blower is mounted on a precision cut
gasketless mounting plate. This plate is held into place
with (3) thumb screws. See Fig. 67.
To remove the combustion blower:
• Turn the thumb screws counterclockwise approximately
5 turns. Rotate the entire assembly counter clockwise until
the points of the retaining slots are visible.
• Remove the blower assembly with the fan blade by
pulling it directly away from the blower housing.
• The cord on the motor is long enough to allow the motor
to be set down on the black plastic fan cover. This allows
for easy access to inspect and clean the area. See Fig.
• With the blower assembly out, inspection should be done
on the surfaces of the blower assembly and the housing
opening where they meet. These surfaces MUST be
clean and free from dirt, grit, flyash, soot or nicks in the
metal. This gasketless seal relies on an extremely close
tolerance. Therefore, anything other than a clean joint
may cause exhaust gases and/or flyash to escape.
• The assembly can only be reinstalled in one position:
with the motor winding in the upward location. See Fig. 67.
The mounting plate will not allow for any other position.
• Always make sure that the assembly is fully seated and
the (3) thumb screws are tightened before operating the
Fig. 66
Fig. 67
Feed Motor
The Control Board/ESP combination is responsible for
all high limit safety control. There are 2 high limits, one normal
operation high limit and one backup high limit. The control has
an automatic diagnostic circuit that continuously monitors the
ESP and Room Sensor for faults. If a fault should occur, the
control sends a status alert and at the same time the unit goes
down to minimum feed/minimum burn as a safety condition.
The Hopper Lid Position Switch is found in the rear
corner of the hopper opening. If the hopper lid is not fully
closed, the switch opens, interrupting the power to the feed
motor and the igniter circuits. This prevents possible injury from
reaching into the feeder mechanism during operation.
Hopper Lid
The Low Draft Pressure Switch is a differential pressure switch that monitors the negative pressure (Draft) in the
firebox. If the draft becomes too low for proper combustion,
the switch opens, cutting power to the feed motor and the
igniter circuits. This switch is connected into the AC (high
voltage) wiring.
Accentra Pellet Insert Safety Devices
Distribution Blower
(under unit)
See Fig. 10, Page 9.
Backdraft Damper Assembly
Always check to see if the damper
plate swings freely inward and that
the seating edges are not covered
with dirt or lint.
Low Draft
Accentra Insert Motor & Component Locations
Motor & Component Locations
1. No fuel in hopper.
2. Firebox draft may be too low for sensing switch in
feeder circuit to operate. Check for closed doors,
loose or missing gasket on doors or hopper lid.
3. Hopper lid must contact the lid position switch.
4. Feed motor will not run until the ESP control
senses a certain temperature. Maybe you did not
put enough fuel or starting gel in the burn pot before
manually lighting the fire.
5. Restriction in the hopper or feeder. Remove all
fuel and examine. Clear the obstruction.
6. Feed motor has failed.
1. Feed rate too high.
2. Poor air to fuel mixture. (Check burn pot cleanout cover and air intake).
3. Burn pot or heat exchanger tubes may need to
be cleaned.
4. Combination of all the above.
5. #6 status blink: A 6 blink control board status
indication is caused by poor or incomplete combustion. The circuit board has the ability to track the
combustion through feed settings and ESP temperatures. When the control board has calculated
poor or incomplete combustion, it will shut down
the unit as a safety feature. (Poor or incomplete
combustion is a contributor of creosote which may
cause a chimney fire)
A 6 blink status may be caused by several
1. Blocked or partially blocked flue.
2. Blocked or partially blocked inlet air.
a. Backdraft damper on the inlet pipe may be
stuck closed.
b. If outside air is installed, the inlet cover may
be blocked.
3. The air chamber under the burnpot may be filled
with fines and small bits of ash.
4. The holes in the burnpot may be getting filled
with ash or carbon buildup.
5. Combustion blower fan blades may need
6. Fuel restrictions as noted above.
Seal the vent pipe joints and connection to stove
with silicone. The exhaust vent is the only part of
the system that is under positive pressure.
FIRE HAS GONE OUT- Check for status light.
1. No fuel in hopper.
2. Draft is too low, blocked flue.
3. Something is restricting fuel flow.
4. Hopper lid not closed properly.
5. Feed motor or combustion blower has failed.
1. Air-fuel ratio is too rich.
A. Feed rate too high.
B. Draft too low caused by a gasket leak.
1. Feed rate too low
2. Draft too low because of gasket leak.
3. Poor quality or damp pellets
4. Combination of 1 and 2.
Helpful Hints
Cleaning Burn Pot
Whenever your stove is not burning, take the opportunity to scrape the burn pot to remove carbon buildup.
A vacuum cleaner is handy to remove the residue. Be
sure the stove is cold if you use a vacuum.
Carbon buildup can be scraped loose with the fire
burning using the special tool provided with your stove.
Scrape the floor and sides of the burn pot. The carbon
will be pushed out by the incoming fuel. Always wear
gloves to do this.
Removing Ashes
Turn the Temp Dial to number 1 approximately 30
minutes before removing ashes. This will result in a
cooler stove and ash pan.
Maximum Feed Adjuster settings are not needed
in most cases. Operating in the normal range (#4) is
recommended when maximum heat output is not required. The ESP probe prevents the stove from being
Keep the stove free of dust and dirt.
The Accentra is approved for burning any grade
of pelletized bio-mass fuel. It is also approved for burning shelled corn in a mixture with wood pellets, up to
50%.(See Page 46)
It should be noted, however, that higher ash content will require more frequent ash removal, scraping of
the burn pot, and may provide less BTU's per pound.
The moisture content of pellets must not exceed
8%, and corn must not exceed 15%. Higher moisture
will rob BTU's and may not burn properly.
Fuel should not be stored within the stove installation clearances or within the space required for charging and ash removal. See Page 14.
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