Newmac BC 160, Installation, Operating And Service Manual

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8
COAL BURNING TIPS
Burn ONLY anthracite (hard) coal of the “chestnut” size. Bituminous (soft) coal is not recommended
because it has a high ash and sulphur content which means more cleaning and greater pollution. Also
bituminous coal produces excessive smoke and an excessive amount of dirt and ash which will plug the
heating unit and the flue pipe possibly causing smoke damage or danger of carbon monoxide poisoning.
Coal is not as easy to burn as wood. It requires patience, and a very specific and regular procedure of
loading, shaking, adjusting, etc. If you do not follow the correct procedure, the coal fire will go out. This
can happen in a very short space of time and once the process of extinction has started, it is almost
impossible to reverse.
After a coal fire goes out, all the coal must be emptied from the boiler and the complete starting process
must be repeated. The coal-burning learning process is often long and frustrating, but once the proper
procedure is established and followed, coal burning becomes a reasonably simple process, with the
benefits of long burn times and evenness of output over the entire length of burn.
STARTING UP A NEW FIRE
The flue draft must be -.05” W.C. to allow combustion gases to flow freely out the chimney. Use paper
and dry kindling to start the fire.
Add small compact pieces of hardwood when the kindling is burning hot. Keep the draft slide plate in the
ash door fully open to establish a hot fire. The ash door may be opened for start-up. However, close the
ash door before opening the fire door to prevent smoke from emitting out the fire door opening.
When a substantial bed of red coals is built up, start adding coal, small amounts at a time. Continue
adding small amounts of coal until there is a solid bed of burning coal. Do not add too much at on time.
Allow sufficient time between each small loading (at least 10 to 15 minutes) so that each loading has time
to thoroughly ignite before the next load is put in. For maximum burning efficiency, always fill the firebox
to the highest level possible. A deep bed of coal always will burn more satisfactorily than a shallow bed.
Keep the draft fan running until you are sure the fire is continuing to burn hot. If the ash door has been
opened, close it to prevent overfiring, which can severely damage the unit.
LOADING
Coal should be added to the fire at least every twelve hours. Coal never should be added unless there is
a reasonably hot fire.
If the fire is burning hot and there is a deep bed of coals, full loads of coal can be added at any time.
However, if there is not a deep bed of coals, it is best to add small amounts of coal at first.
SHAKING
Shaking should be done only with a hot fire.
Shaking should be done at least once a day, but not more than twice a day.
Best results from shaking will occur if short “choppy” strokes are used rather than long even strokes.
The amount of shaking is critical. Too little or too much can extinguish a fire due to blocked air flow. The
proper amount normally occurs when the red coals first start to drop through onto the bed of ashes. Be
sure that a small amount of ash is left on the grates to protect them from the direct heat of the burning
coal.
MAINTENANCE
Ashes never should be allowed to accumulate in the ash pit so 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 they cannot cool from a flow of air beneath them. Ashes MUST
be removed daily and put in a metal container with a lid.
Clinkers can occur in any coal burning unit. They are pieces of fused ash that are hard. They can
become large, and therefore cannot be shaken through the grates in a coal furnace. When there is an
appreciable accumulation, the fire will go out because insufficient air is allowed to pass through the
clinkers to the burning coal.
Once clinkers have formed, they can be removed only from above the
grates. This usually means the fire must be allowed to die out before they can be removed.