Starter said:
Btw I'm somewhat embarrassed to post this but it's the language barrier I think... I've been reading the FAQ on choosing stoves, woodburning etc on hearth.com and there are a couple of words I am not understanding what they refer to. Mainly, what is a flue, a baffle and a damper? :red:
I'm chiming in because I'm not sure your question has been answered real well yet.
Don't worry to much about the language, you do better than many native american speakers - our gov't education system is nothing to brag about. I think anyone might be confused by some of the technical terms.
A flue is not quite the same as a chimney. A chimney is a brick or metal structure that contains one or more flues. The flue is actually the pipe or passage that the smoke travels through. Typically the rule of thumb is that each fuel burning appliance, such as a furnace, stove, fireplace, etc. will need to have it's own seperate flue, so many times they will put several flues into the same chimney structure, especially when dealing with masonry chimneys.
A damper is sort of like a valve in the flue that controls the flow of exhaust gasses. These days the term is a bit ambiguous because there are really two different sorts of dampers, that serve two different functions.
The older traditional type may or may not be needed with a modern stove, but was very important on older stoves. It is typically either at the exit from the stove or somewhere in the flue passage. It controlled the effective size of the flue, and thus restricted the total airflow through the stove. On a modern stove, it is usually not needed unless the flue has an unusually powerful draft that can over-ride the modern stoves normal controls. In that case, adding a damper can restrict the effective flue volume so that the stove works better. (Draft, or draw, is the force that pulls the smoke up the chimney, it is influenced by many things, including the height, construction and size of the flue, the outside temperature, how hot the stove is, etc. )
In a modern stove, there are several techniques used to make it more efficient and cleaner burning. Many of these involve restrictions and extra chambers for secondary combustion, which work well once the stove is burning well, but can be too restrictive when the stove is being lit, or when you open it up to add more wood, so that the stove would blow smoke into the room. To deal with this, many stoves use a "bypass damper" that is usually internal to the stove body, and which (as the name implies) opens and closes a larger passage around those restrictions so that the stove won't smoke when you open the doors, and allows you to get it lit or get reloads burning well. This is one of the main controls on the stove itself.
A baffle is a part that is found in some stoves and not in others, and takes several different shapes and locations, and can be made from lots of different things depending on what the stove designer wanted it for. Some stoves might even have several baffles. Essentially what they do is control the movement of air and combustion gasses through the stove so that you get the most efficient combustion possible. Usually they aren't an item of major concern, however on some stoves they may need to be removed as part of the stove maintanence procedure, and on other stoves they are made out of relatively fragile material that you need to be somewhat careful to avoid damaging.
Next issue... Chimney fires.
Chimney fires are caused when excessive creosote builds up in the flue, and gets ignited by a hot fire. Creosote buildup is normally dealt with by developing good burning habits, and by proper periodic flue cleanings. If you don't have excess creosote, you are unlikely to have a fire in the process, so the number one step in preventing fires is preventing the creosote buildup in the first place. Fortuneately, modern stoves are far better about this than old units. The more efficient burning you get with a new stove also means there is less creosote going up the flue in the first place.
However if you DO have a chimney fire, you are potentially in big trouble! Creosote burns extremely hot, and as it burns generates tremendous draft in the flue, which adds air, making it burn hotter, in a self perpetuating cycle that will last until you either manage to shut off the air flow or the creosote all gets consumed. While it is burning, it may be shooting flames out the chimney, and blowing burning material all over the neighboorhood. You essentially have a giant blowtorch going inside your chimney! A large part of the reason codes require chimneys and flues to be built the way they do is to hopefully keep the fire contained inside the chimney structure. If it weren't for chimney fires, we could probably build much lighter chimneys...
If the fire is contained inside the chimney, it is spectacular, but not a big problem - typically you would want to get an inspection to make sure the structure is still sound, and possibly you'd have to replace some or all the chimney parts.
If the fire breaks out, you have a big blowtorch flame trying to get anything inside the house going that it can reach.... You now have a major fire more or less like one from any other cause - how much damage does a major fire typically do with your style of house construction? You probably will be better off than a typical american house made with wood framing and lots of other combustible materials, but I suspect it is still a serious problem.
About the only potentially "good" thing about a chimney fire, is that you will KNOW if you have one - they are typically compared to a jet airplane landing on your roof, or maybe a heavy freight train running through the living room. This gives you the warning to call the fire department and prepare to evacuate.
(almost out of room - will continue)
Gooserider
I've learnt a ton over here than any agent/installer ever taught me!
