Harman Stove Company SF160 - Manual (Page 11)

11
Operation
Starting a Coal fire
Make sure the boiler and all piping is full
of water and that all air has been purged from the
system.
Never start a fire without water in the
system. An explosion will occur.
Turn on electrical power to the boiler. This
should cause the automatic draft control to open.
Open the ash pan door to allow free air move-
ment. Use the same procedure as starting a wood
fire except, do not load the larger diameter wood
Use wood about 2 in. diameter maximum. This
size will form a very hot charcoal bed in less time.
Again, the ash pan door may be opened periodi-
cally to speed the ignition process.
DO NOT LEAVE THE BOILEr uNATTENDED
WITH ANy DOOr OpEN.
When you have accumulated a substantial
charcoal bed, start adding a thin layer of coal. Pea
or Nut sized coal is better for starting than Stove
coal.
When the first layer is burning with some
blue flame, continue to add thin layers of coal until
there is a solid bed of burning coal. Let each layer
burn a blue flame before adding another layer. Ad-
ditional coal can be layered in until the bed is ap-
proximately 10 inches deep. By now, you should
have the ash pan door closed, and the automatic
draft control will continue to regulate the fire.
The idle air adjuster may need to be set for
slightly less air for coal than wood. Here again,
experience will dictate the best setting. The maxi-
mum air bolt can be turned all the way “counter-
clockwise” to allow for a quicker recovery. Never
adjust this bolt with the flapper open.
The two manual draft controls, on the
firebox door, are used to allow secondary air to
pass over the fire when burning coal. This helps
to burn the gasses that are emitted from the coal
as it is heated. Your setting for these draft controls
should be between 1/2 and 1 complete turn from
closed. Adjust both controls equally.
Loading
Coal should never be added unless there
is a reasonably hot fire. The coal bed should be
bright and vigorous. If you have an active coal
bed, full loads can be added at any time. If not,
add new coal in layers, as described in starting a
coal fire.
Shaking the Grates
Shaking should be done only when there
is a well-established fire. The frequency of shak-
ing will depend on the degree of burning. Twice
a day shaking is recommended. The best results
are achieved with short, choppy strokes as op-
posed to long, even strokes. Full rocking of the
grates may allow burning coal to fall into the ash
pan. The amount of shaking is critical, too much
can disrupt the fire bed, and too little will restrict
air-flow. The proper amount of shaking is normally
achieved when hot red coals first start to drop
through the grates into the ash pan.
Every effort should be made to not let a
coal fire burn down too low. This will cause the
reloading process to be much longer, with a real
good chance of losing the fire altogether.
Do not shake or stir with a low fire. Open
the ash pan door to get maximum air flowing into
the firebox. Once burning is restored, close the
ash pan door and add a layer of coal to the fire
bed. Follow the instructions under Starting a Coal
Fire. When the new coal is thoroughly ignited, and
there is a substantial bed of hot coals, the grates
may then be shaken.
Ashes and Ash removal
Ashes should never be allowed to accu-
mulate above the top of the ash pan. Ashes in
contact with the bottom of the grates act as insu-
lation, which intensifies the heat on the grates and
causes them to sag or warp. Also, too much ash
accumulation will restrict air-flow which will make
fire maintenance more difficult. Place ashes in
a sealed metal container, outside, until they are
cooled enough for final disposal. Coal produces
considerably more ash than wood, so the intervals
between emptying are much shorter.