Harman Stove Company SF-150 SF-250 manual

the fire has started to die. This will cause the reloading process to be much longer, and there is a good possibility of losing the fire.

Do not shake or stir with a low fire.

Open the draft control wide or open the ash cleanout door to get the maximum draft.

Run the stove with the draft control or ash door fully open until the fire is reasonably hot.

Start adding small amounts of coal. Follow the same procedure as in paragraphs 3 and 4 in Section 11.2

When the new coal is thoroughly ignited or there is a substantial bed of hot coals, the stove may be shak- en thoroughly. Be sure to shake down all ashes (but do not over- shake).

After shaking, keep the bottom draft control open until you are sure the fire is continuing to burn hot, then turn the draft control down to the proper operating level. IF THE ASH DOOR HAS BEEN OPENED, BE SURE TO SHUT IT (SERIOUS DAMAGE CAN RESULT IF THE STOVE IS RUN FOR EXTENDED PERIODS WITH THE ASH DOOR OPEN).

Count the exact number of turns from full shut to the normal operat- ing positions so that you can adjust the stove to the exact level of heat output and length of burn you desire.

11.5Shaking

Shaking should be done only when there is a hot fire.

The frequency of shaking will depend on the type of stove and the degree of burning. Shaking should be done at least once a day, and preferably twice a day.

Best results from shaking with Harman grates will occur if short “choppy” strokes are used rather than long, even strokes.

The amount of shaking is critical. Too little or too much, either can result in the extinguishing of a fire due to blocked air flow. The proper amount normally occurs when red coals first start to drop through onto the bed of ashes.

11.6Draft Controls

The heat output of the coal is con- trolled by the primary draft control on bottom door. Experience will dic- tate the proper settings for heat requirements.

Coal responds very slowly to changes in the draft settings. Because of this slow response time, over-correcting is a common prob- lem. When changes in heat output are needed, make only small changes in the draft setting and wait for the temperature to stabilize.

11.7Secondary Air

The two draft controls on the top door are used to allow secondary air to pass over the fire when burning coal.

This adds oxygen to the unburned gases (primarily methane and car- bon monoxide) and aides in burning them. The setting for normal burn- ing is from 1/2 to 1 turn open from closed position. Adjust both controls equally. NOTE: THESE SAME CONTROLS PROVIDE THE PRI- MARY AIR WHEN BURNING WOOD.

11.8Ashes

Ashes should never be allowed to accumulate in the ash pit so that they in any way impede the flow of combustion air to the fire. Excess ash accumulation can cause the fire to go out and also can cause severe damage to the grates because of the absence of a cooling flow of air beneath them.

Ashes should be placed in a metal container with a tight fitting lid. The closed container of ashes should be

placed on a noncombustible 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 outside the dwelling.

CAUTION! ASHES SHOULD NEVER BE ALLOWED TO ACCU- MULATE ABOVE THE TOP OF THE ASH PAN. ASHES IN CON- TACT WITH THE BOTTOM OF THE GRATES ACT AS AN INSU- LATOR, INTENSIFYING THE HEAT ON THE GRATES, AND COULD CAUSE THEIR WAR- PAGE. WITH AN EXCESSIVE ASH BUILDUP, PRIMARY COM- BUSTION AIR IS RESTRICTED (IN COAL MODE); THUS, THE UNIT’S OUTPUT COULD BE REDUCED!

Coal produces considerably more ash than wood, so the intervals between emptying are much short- er. For equal heat output, coal will produce seven to ten times more ash than wood.

11.9Safety

Whenever a loading door is opened, it always should be cracked slightly to allow oxygen to enter and burn any combustion gases that are pres- ent before fully opening. Failure to do this could result in sudden igni- tion of the unburned gases when the door is opened.

A stove never should be filled with excess coal so that the flue gas exit is blocked or impeded in any way. Burning coal generates carbon monoxide. If the flue gas exit is blocked, the carbon monoxide can be forced out of the stove into the room, with possible fatal consequences.

WITH THE EXCEPTION OF THE START-UP PERIOD, AN ASH PIT DOOR SHOULD NEVER BE LEFT OPEN.