Harman Stove Company 1-90-797000 C. The Combustion Process, Doors, Front Door, Ash Door, Grates

Models: 1-90-797000

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2. Doors

Oakleaf Woodburning Stove

2. 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 Oakleaf 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.)

C. The Combustion Process

Combustion in the Harman Oakleaf is precisely con- trolled and is best explained in two parts.

During a wood fire, combustion air enters at the bot- tom front of the stove where it travels upward through channels at either side of the front door. From the mani- fold 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 "Fire- dome" 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 ventillation to the room where the apliance is located, to prevent air star- vation. In tight construction, consider installing outside air to the appliance.

3. Grates

The Harman Oakleaf's unique grate system consists of one flat bottom grate, and two front

EXHAUST STREAM

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

SECONDARY AIR ENTERING EXHAUST STREAM

SECONDARY AIR

THRU BRICK

SECONDARY AIR THRU RAMP BRICK

or change the configuration of this grate system.

SECONDARY AIR FLOWFront Door

PRIMARY AIR FLOW

PRIMARY & SECONDARY AIR FLOW

Save These Instructions

3-90-798

Dry Seasoned Wood Only!

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Harman Stove Company 1-90-797000 manual C. The Combustion Process, Doors, Front Door, Ash Door, Top Load Door, Grates