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It is important to know that for high, combustion efficient, clean burns,
you will need to have sufficient temperatures inside the firebox for
thorough combustion. The best method for determining if you have
sufficient temperatures is to watch the brick lining in your firebox. When
you first light your stove, the bricks will turn a dark brown or black.
After 20 to 30 minutes of a hot fire, most of the bricks should return
to near their original light brown or yellow color. This means the bricks
have reached a high enough temperature for your stove to achieve high
combustion efficiency.
Second and just as important, is achieving a high level of heat transfer
efficiency. Slowing the rate of flow through the stove or insert enhances
heat transfer, thus allowing more time for heat to be transferred into your
home. To do this, be sure to thoroughly preheat your stove and then reduce
the amount of primary air by closing the draft control (lower left) to about
1/2 to 3/4 open. This will decrease the excess oxygen in your flue, which
carries heat up your chimney, but should still be enough air to allow the
stove to produce its maximum heat output. (More air may produce a lightly
greater amount of heat, but will greatly increase wood consumption). When
the area being heated reaches a comfortable temperature, slow the burn
rate by closing the control to further improve heat transfer.
To get the most out of your appliance, you will need to combine good
combustion efficiency with good heat transfer practices. The following
are some tips on how to operate your stove to achieve the highest overall
efficiency.
1. Thoroughly preheat your stove before slowing the burn rate by closing
the draft control.
2. Measure the stove temperature at the hottest point on the stove top
or face. Use this information to repeat burn rates.
3. Once preheated, add wood (if needed) and partially close the draft
control (lower left).
4. Operate your stove as much as possible in the low to medium burn
ranges.
5. Do not lower the draft setting so low as to completely extinguish the
flames in the firebox. Check for at least some small flames 20 minutes
after setting the draft control.
6. Do not continually operate your stove in the high (wide open) setting.
This wastes wood by carrying a great deal of heat up the chimney
and can damage your stove and chimney.
7. Go outside and check your chimney. More than a very small amount
of smoke indicates wasted heat, creosote build-up and pollution.
MAXIMIZING YOUR STOVE’S OVERALL EFFICIENCY
Recent developments in wood-burning technology have made wood-burn-
ing a cleaner and more convenient way to heat your home. Overall efficiency
in a wood-burning appliance is a combination of combustion efficiency
and heat transfer efficiency. Whether heating your entire home, or just a
room or two, your understanding of how to best operate your stove or
insert will enhance its overall efficiency and performance. What this can
mean to you is longer, cleaner burns, less wood use and more heat.
OPERATING TECHNIqUES AND HINTSGETTING THE MOST OUT OF YOUR STOVE
The following sections will outline techniques you can use to “get the
most out of your stove.” Please read them carefully.
To achieve long burn times, after having thoroughly preheated the
stove, let the stove top cool down to 275 to 400 degrees (on Elites,
locate thermometer on the face of the insert just above the door). Now
load the firebox and set the draft control. At this point, you may need to
burn the stove with the draft open for a few minutes to ignite the wood.
All Lennox Hearth Products stoves are EPA tested for emissions at low
burn with the air control completely closed. Whether or not you should
burn your stove with the air control completely closed will depend on
the following factors.
* How you load your wood
* Your chimney type, height and draft
* Your wood type and its moisture content
* The temperature of the stove
* Which model stove or insert you have
Experiment with different loading configurations to achieve longer
burns. Try loading the wood from side to side and nesting it in the ashes
to prevent airflow under and around the wood. Fresh wood should be
loaded to the back of the firebox or to the sides. Hot coals or half burned
wood should be brought towards the front of the firebox. The way you
load your wood can seriously affect burn times. If the new load does not
ignite within a few minutes, try crisscrossing the load to allow more airflow
around the fire, or try a slightly hotter stove temperature.
Determining the lowest setting for efficient low burns. This will require
some experimentation on your part. Try closing the air control all the
way with the stove temperature at 325 to 350 degrees. If the flames are
completely extinguished, open the air control halfway and then slowly
close it until there is only a small amount of flame. It is important to check
the stove about 20 minutes after setting the draft control as it takes this
long for the stove temperature to stabilize. There should still be some
small flames on or above the wood load.
Use 325 degrees as a starting point. You can try starting temperatures
25 degrees higher or lower to achieve desired burn times, start 25 degrees
lower if the stove burns the wood too quickly or 25 degrees higher if there
are no flames in the firebox for more than a few minutes after loading the
wood. You may or may not need to burn the stove with the air control
open for a few minutes prior to setting the draft for a low burn, this will
depend on the factors mentioned above. Be sure not to smolder a fire
overnight. Check your chimney for large amounts of smoke as this
indicates very poor combustion.
It is important to realize that stove technology has changed. Stoves
have changed a great deal in the last few years. This has led to substantial
changes in the methods of operation in new stoves as compared to older
stoves. In old stoves without full brick linings and ceramic insulation,
the rule was “get the stove as hot as possible before setting the draft on
low for overnight burns.” On newer, high technology stoves, this is not
necessary. Although it is still important to have the stove hot enough to
burn efficiently, it will require less preheating. Once you have determined
your optimum operating temperatures for various burn rates, we believe
you will find your stove an extremely convenient way to achieve your
heating needs.
Do not reload the stove for long burns when the stainless secondary
tubes or baffles are glowing red, or when the stove is uncomfortably
hot to load. This indicates the stove is too hot to load for a long burn.
Also, do not load wood for a long burn on a deep bed of hot coals. Try
stirring the coals a few minutes before loading the stove for a low burn
to allow some of the unburned coals time to burn.
ACHIEVING CLEAN, LONG BURNS