Empyre Elite XT 100, Installation And Operation Instructions Manual

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OPERATION
EMPYRE ELITE XT INSTALLATION AND OPERATION MANUAL 17
Understanding the Gasification Process of
the Empyre Elite XT Wood Furnace
Wood gasification is an amazingly clean burning and
efficient process! It is a process where much of the solid
fuel is converted to gases. These gases ignite and burn
along with the solid fuel. A large percentage of wood is
converted into gases. In order to burn these gases there
must be the right amount of air, as well as temperatures of
well over 1000ºF (538ºC). Gasification is accomplished in
the Empyre Elite XT furnace because:
a) air flow is engineered to provide the correct amount of
under fire and over fire air. This setting is calibrated for
burning seasoned wood;
b) temperatures high enough to burn the gases are reached
in the insulated chamber below the firewood.
A key factor in the gasification process is the wood itself,
the type of wood, the moisture content, diameter, length
and placement in the firebox. The Empyre Elite XT furnace
is not difficult to operate using seasoned wood and by
using the following guide it will also work well even when
using less than ideal wood.
The gases in the wood are released when the wood surface
is exposed to the fire. The more surface area of a piece of
wood that is exposed and the drier the wood is, the faster
the gases are released. Example: A small DRY piece of
burning firewood will release gases much faster than a
large WET piece of firewood.
Scenario 1: in the case of the small DRY piece of firewood
which has a lot of exposed surface area, the gases are
released rapidly and the fire burns very hot but it is starving
for air due to the high volume of gases. This will eventually
create smoke.
Scenario 2: in the case of the large piece of WET firewood
that, in proportion to its mass, has little surface area and
will release gases slowly. In this case there is too much air.
The air is now cooling the fire resulting in blue smoke and
very little heat.
Generally speaking, when burning extremely dry firewood,
pieces should be over 5” (12.7 cm) in diameter. If using
high moisture wood, use pieces that are less than 5” (12.7
cm) in diameter. It is good to mix the dry and wet wood
when possible. When using the recommended seasoned
wood, where the moisture content is between 19% and
25%, the diameter of the wood is not that important.
Scenario 1 is also created when stirring a hot fire. Scenario
2 is also created when firewood is too short in relation to
the length of the firebox. Correct length of firewood for the
Empyre Elite XT 100 is 18” - 25” (45.7 cm - 63.5 cm)
, the
Elite XT 200 is 20” - 28” (50.8 cm - 71.2 cm).
Stack wood pieces side by side. If pieces are short place
them end to end making one long piece. Firewood should
be centered front to back over the brick slots.
Scenario 2 is also created when wood bridges in the
firebox. This is often due to wood with high moisture or
lack of careful placement of the wood. Scenario 2 is also
created when starting up a cold furnace. Only a small
amount of wood is burning with a lot of excess air.
Identifying Smoke Verses Condensation
Mostly the exhaust from the chimney will be clear. There are
times soon after loading the furnace when a gray vapour
may appear. This vapour disappears soon after leaving the
chimney. This vapour is moisture being released from the
wood. Smoke is more blue in colour and will not disappear
as quickly as the gray vapour. On a cold winter day what
looks like smoke may only be vapour.
Loading Wood into the Firebox
1. The right time to add wood is when there still is a good
layer of charcoal or wood left, but not so much that it
is difficult to stir.
2. Using the ash rake, gently pull the charcoal away from
the back of the firebox. Stir the charcoal sufficiently
so that ash falls down through the brick slots. Always
ensure that the brick slots are not blocked by ash
buildup. Place wood into the firebox, DO NOT throw, as
this may damage the brick lining.
Correct:
The firebox should be loaded with
wood of proper length. This will
lengthen the burn time.
Incorrect:
The firebox loosely filled with irreg -
ular pieces of wood will decrease
burn time and may cause unneces-
sary bridging.
Larger diameter and irregular shaped logs are more
likely to cause wood to hang up or ‘bridge.’ Place the
larger logs on top.
3. Load wood into the firebox.
Centre wood in the firebox. There should be a gap
of several inches between the wood and both
the front and back of the firebox. Placing wood
up against the back of the firebox can result in
unburned wood which can cause logs to hang up.