Combustion Process - Harman Oakwood Wood Stove Owner's Manual

Oakwood Woodburning Stove
Doors
Your stove has a large glass-paneled door for loading and
fire viewing, a separate smaller door for removing ashes and
a top loading door.
Front Door
Before opening, always check for wood, embers, or ash that
may be ready to fall out of the door.
To open the glass door, open the bypass damper first, then
turn the handle clockwise and pull out; to close the door, push
the door closed with the handle in the open position, then
turn, counter-clockwise, to engage the latch.
Ash Door
To open the ash door, lift up the handle and pull out. Close the
door by pushing in and pushing the handle all the way down.
Top Load Door
To open the top load door, open the bypass damper and then
lift to open the top load door.
All doors must be closed while the stove is in normal
operation, and the gaskets routinely examined for wear and
replaced when necessary. Good door seals are important
for maintaining control of the stove. Never operate with the
ash door open. Operating the stove with the ash door open,
or with a door inadequately sealed, could create a serious
overfiring condition (discussed later in this section).
The glass used in your Oakwood 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
(See instructions in the Maintenance section.)
Grates
The Harman Oakwood's unique grate system
consists of one flat bottom grate, and two front
andirons. The bottom grate has slots which allow
the ash to fall into the ash pan by passing a poker
back and forth across the grate. The andirons keep
the fuel from coming into direct contact with the
glass, and keep hot coals and embers from spilling
out while reloading. Never build a fire directly
against the glass.
The grates and andirons must remain in place
at all times. Do not tamper with or change the
configuration of this grate system.
3-90-08327
SECONDARY AIR ENTERING
EXHAUST STREAM
SECONDARY AIR FLOW
Harman® • Oakwood Owner's Manual_R34 • 2004 -___ • 09/15
C. The Combustion Process
Combustion in the Harman Oakwood is precisely controlled
and is best explained in two parts.
During a wood fire, combustion air enters at the bottom front
of the stove where it travels upward through channels at either
side of the front door. From the manifold located above the
front door, it is directed into the firebox as a sheet of air flowing
between the glass and the wood. This concept helps to keep
the glass clean, while providing the oxygen needed to sustain
burning. This is what is known as "Primary Combustion".
Additional air enters at the bottom rear of the stove body.
Some of this air enters through holes in the rear bricks
where it is used to revitalize the fire at the rear of the firebox.
The remainder is delivered into the "Firedome" combustion
package where the "Secondary Combustion", or re-burning
of the smoke, occurs.
During combustion, the burning of wood proceeds through
several stages. The initial or evaporation stage is where
the moisture in the wood is driven off in the form of steam.
A second stage is where the volatile gases contained in the
wood are released and burned. This represents most of the
wood's heating capacity. The final stage is the charcoal stage
where the charcoal burns the remaining heat content in the
wood fuel. Ash remains after the burning is complete. Within
the primary firebox two or more of these stages of combustion
are occurring at once.
Always be sure to provide adequate ventilation to the room
where the appliance is located, to prevent air starvation.
In tight construction, consider installing outside air to the
appliance.
EXHAUST STREAM
PRIMARY & SECONDARY AIR FLOW
SECONDARY AIR
THRU BRICK
SECONDARY AIR THRU
RAMP BRICK
PRIMARY AIR FLOW
Dry Seasoned Wood Only! 27