Ok I'm confused is this the stove you have / also what size coal are you burning ?
This link is broken, either the page no longer exists or there is some other issue like a typo.
if it is then why does it state this in the ad
Wood Stove WarmthMODEL 1500
The NORSEMAN� 1500 Warm Air Add-on Furnace works as a primary or supplementary source of heat for your entire home or workshop area.
Conserve dollars spent on conventional heating methods using this solid fuel efficient wood/coal furnace.
This add-on furnace comfortably heats most small to medium homes with an output of 30,000 to 90,000 BTU's.
In the event of a power failure, the Norseman will continue to provide heat on a low setting.
Norseman furnaces are designed for INDOOR installation only.
(Not Applicable for Anthracite Coal Firing)
Coal Burning Tips
The size of coal fuel is critical - too large and it won�t burn well, too small and it will smother the fire creating excessive smoke and gases. Purchase Bituminous coal �nuggets� that are 1-3/4� to 4� diameter and that have been �cleaned� to remove rocks and other minerals.
Bituminous coal is recommended for ease of use but produces a greater amount of volatile gases so it is important to build and refresh coal fires properly. Extra maintenance will also be required to remove accumulated
soot on heating surfaces and pipes.
All fires should be initially started using wood kindling. Hardwood is best as it creates a hotter bed of coals that is necessary to ignite the coal.
Once a hot bed of wood coals has been established an initial layer of coal may be placed in the firebox. Due to the high amount of volatile gas produced by coal, the initial flames will be long and of an orange or yellow color accompanied by quite a bit of smoke. As the gas is burned off the flames will become shorter, the color will change and less smoke will be produced.
Once the fire is well established, add coal to the center of the firebox in a conical arrangement. The highest
part of the fuel should be in the center of the fire box. This allows the heat to drive off the volatile gases and the turbulence created causes a more efficient burn.
Remember to allow enough secondary air to enter the fire box and keep the stove pipe damper open to properly burn off the volatile gases. You will have to experiment with your particular setup (fire construction,
fuel load, spin draft control, damper and automatic settings) as no two arrangements of furnace/chimney are the same.
When refueling a coal fire, use a poker to break up any crust that may have formed being careful not to mix the coal which may increase the chance of forming �clinkers.�
Banking a Coal Fire
A fire should be banked for extended operation without tending, such as overnight. This is accomplished by heaping the fuel along the sides and back of the fire box so that the fire gradually burns through the fuel. This reduces the intensity of the fire without letting it go out.
Use the same procedures as in refueling but without shaking the grates. The layer of ash will help to reduce the intensity of the fire. After loading the fuel in this manner, let the fire establish itself for about 30 minutes then close the damper and adjust the automatic control to a point so that the house does not get too cold. Make sure you leave yourself enough time to bank the fire before leaving or retiring so you can make the necessary adjustments after the fire has become well established.
Reviving a Fire
To revive a fire that has almost gone out, increase the draft through the grates by opening the ash door and stove pipe damper and closing the door spin draft control(s). Place a thin layer of new coal over the entire fire but DO NOT SHAKE the fire grates. Doing so may cause the live coals to drop through the grates. Once the fresh layer of coal has ignited you may shake the grates (slightly) and refuel as usual.