Vermont Casting 2477 User Manual

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Your stove requires a dedicated flue. Do not connect the 
stove to a flue used by any other appliance. Chimney 
draft is a natural form of energy and follows the path of 
least resistance. If the stove is vented to a flue that also 
serves an open fireplace or another appliance, the draft 
will also pull air in through those avenues.
 The additional air flow will lower flue temperatures, 
reduce draft strength and promote creosote development; 
overall stove performance will suffer. The effect is similar 
to that of a vacuum cleaner with a hole in the hose. In 
some extreme instances, the other appliance can even 
impose a negative draft and result in a dangerous draft 
reversal.

Even the best stove installation will not perform well with 
poor fuel. If available, always use hardwood that has 
been air-dried (“seasoned”) 12-18 months. Softwood 
burns more rapidly than hardwood and has a high pitch 
content that can result in creosote. Decayed wood of any 
type has little heat value and should not be used.
Unseasoned (‘green’) wood has a high moisture content. 
Much of its heat value will be used to evaporate moisture 
before the wood can burn. This significantly reduces the 
amount of energy available to warm your home, as well 
as the intensity of the fire and temperature of the exhaust 
gas. Incomplete combustion and cool flue temperatures 
promote creosote formation and weak draft.
You can judge the moisture content of wood by its ap-
pearance and weight or use a commercially available 
moisture meter for an exact measurement. Unseasoned 
wood will be a third heavier than dry wood. Also, look for 
cracks (“checking”) in the ends of the log that result from 
contraction as the wood dries. The longer and wider the 
cracks are, the dryer the wood is.

Creosote is a by-product of low-temperature stove op-
eration, weak draft, or both. It is a tar that results when 
unburned gases condense inside the flue system at tem-
peratures below 290˚ F. Creosote is volatile and can gen-
erate a chimney fire. All of the installation characteristics 
that adversely affect chimney draft also promote creosote 
condensation. Consequently, you can minimize creosote 
accumulation with an effective chimney design and the 
use of operational techniques that encourage good draft 
and complete combustion.

Inspect your chimney frequently and clean it whenever 
accumulation exceeds 1/4”.

Backpuffing is a condition that results when the draft is 
too weak to pull flue gases out of the chimney system as 
fast as the fire generates them. Volatile gases build up 

within the firebox until reaching a density and temperature 
at which they ignite. With this ignition, you may hear a 
muffled popping sound and see a bit of smoke forced out 
of the stove. 
This condition is most likely to occur in the Spring or Fall 
when moderate outdoor temperatures and low intensity 
fires produce weak draft. If your stove back-puffs, open 
the damper to let the smoke rise to the flue more quickly. 
Also, open the air inlets to induce a livelier fire and speed 
airflow through the stove. Avoid large loads of firewood at 
one time. You should always see lively, dancing flames in 
the firebox; a lazy, smoky fire is inefficient and will pro-
mote draft problems.

An easy way to determine whether your chimney draft is 
strong enough is to close the stove damper, wait a few 
minutes to let the airflow stabilize, and then test whether 
you can vary the strength of the fire by swinging the air 
control open and closed. Results here are not instant; you 
may need to wait a few minutes for a change in the air 
control setting to have an effect on the fire. If there is no 
change, the draft is not yet strong enough to let you close 
the damper. You will need to open it for a while longer and 
manage the fire with the air inlet until the draft strength-
ens. 
Keep a record of your operating habits and relate them to 
their effects on the stove’s function.  You’ll be rewarded 
with safe and efficient performance. 

Good draft also depends on a sufficient supply of air to 
the stove. The chimney can’t pull in more air than is avail-
able to it. Sluggish draft can be caused by a house that is 
tight enough to prevent the ready flow of air to the stove, 
or by competition between the stove and other appliances 
that vent indoor air to the outside; i.e., exhaust fans for 
range hoods, clothes dryers, bathroom fans, etc. 
If the chimney draws well when all such equipment is 
turned off (or sealed, in the case of fireplaces and/or other 
stoves), you need to be attentive in timing the use of the 
other appliances. If you need to crack a nearby window 
or door to enable the chimney to pull well, you should 
install an outside-air intake to bring combustion air  into 
the room.

Woodburning is more an art than a science. Art includes 
technique; and since installations, homes, and fuel vary, 
the stove operator must also vary technique, (mostly 
timing), to achieve satisfying results. Over time, you will 
become familiar with the features of your particular instal-
lation; you will be able to identify cause and effect in a va-
riety of seasonal circumstances, and adapt your operating 
habits to changing conditions.