Vermont Casting 2550CE 사용자 설명서

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Creosote is a by-product of slow wood-burning. It’s an 
organic tar that can condense in the flue if it’s dense in 
the smoke, and slow-moving, and cools off to less than 
143° C (290° F). Condensed creosote is volatile, and 
can generate chimney fires if it gets hot enough. All the 
features that affect chimney draft also affect creosote 
condensation - so use whatever combination of installa-
tion features and operational steps will encourage good 
draft and minimize creosote production.
Because letting the smoke cool off and slow down is 
one of the keys to creosote production, it makes sense 
to line a chimney to match the stove’s outlet size, for 
safety reasons as well as performance. Consult a quali-
fied installer and check local and national codes for 
recommended chimney size.

Even the best stove installation will not perform well 
with poor fuel. The best fuel is hardwood that has air-
dried 12-18 months. Softwood burns, but not as long as 
hardwood. Fairly ‘green’ wood has a good amount of 
moisture in it; it will burn, but some of the heat potential 
is used to drive the remaining moisture off the wood. 
This reduces the amount that reaches your home and 
can contribute to a creosote problem. There are mois-
ture meters available for firewood; you can also judge 
your wood by its appearance and weight. If you get it 
green, lift a piece and get a sense of its weight; it can 
lose a third or more of its weight as it dries. Also look at 
the ends of a log; as it dries it shrinks and often cracks. 
The more weathered and cracked a piece is, the drier 
it is.       
Dry wood burns readily with a good chimney draft. But 
with modern stoves, especially catalytic ones, the wood 
can be too dry. While extra-dry wood has little creosote 
in it, the remainder can ‘gas out’ from the wood quickly 
and densely enough to overload the catalytic burner. 
If you hear a rumbling or roaring noise, like a propane 
torch, from the stove, that is a sign the catalyst is seri-
ously overfiring. The catalyst is a platinum film on a 
ceramic base; the metal can get to higher temperatures 
than the ceramic can take, and overfiring the catalyst 
can break it.  Dry wood can also burn out faster than 
you want. If your dry wood burns out too quickly or 
overloads the catalyst you can mix in greener wood to 
slow the fire down. 

Back-puffing results when the fire produces volatile 
gases faster than the chimney draft pulls them out of 
the firebox. The gases back up in the firebox till they’re 
dense enough and hot enough to ignite. If your stove 
back-puffs, you should open the damper to let the 

smoke rise to the flue more quickly, let more air into the 
firebox, and avoid big loads of firewood. You should 
always see lively, dancing flames in the firebox; a lazy, 
smoky fire is inefficient, can lead to back-puffing, and 
can contribute to creosote buildup in the chimney. 

An easy way to test your chimney draft is to close the 
stove’s damper, wait a few minutes to let the airflow 
stabilize, then see whether you can vary the strength 
of the fire by swinging the air control open and closed. 
Results are not always 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’s no change, then the 
draft isn’t strong enough yet to let you close the damper, 
and you’ll need to open it for a while longer and manage 
the fire with the air inlet until the draft strengthens. If you 
keep track of your burning habits and relate them to their 
effects on the stove’s operation, you’ll be rewarded with 
good performance and a safe system.
In many cases, local or national codes require the 
installation of permanently open air vents, particularly 
with larger appliances (i.e. above 5 kW). Refer to these 
codes to determine specific requirements for your 
installation.

Good draft also depends on a supply of air to the stove; 
a chimney can’t pull in more air than is available to it. 
Sluggish draft results when a house is tight enough to 
prevent the ready flow of air to the stove, or by competi-
tion between the stove and other equipment that sends 
indoor air outside - especially power-driven equipment 
like range hoods, clothes dryers, etc. If the chimney 
draws well with all other equipment turned off (or 
sealed, in the case of fireplaces and/or other stoves), 
then you simply need to be careful with timing the use 
of the other gear. If you need to crack a nearby window 
or door to enable the chimney to pull well, that’s a sign 
that you should install an outside-air intake to bring 
combustion air directly to the stove. For most of our 
stoves we carry adapters to attach to the stove to con-
nect an air duct for outdoor combustion air.

Wood-burning is an art rather than a science. Once the 
stove and chimney system are in place, you can only 
vary your technique, mostly your timing, to achieve 
good results. If you keep track of your burning habits 
and relate them to their effects on the stove’s operation, 
you’ll be rewarded with good performance and a safe 
system.