Would this work with a chimney fire?

[webbie]

Another point - in relation to the masonry getting "hot" on the outside. Lab tests by OMNI when they were trying to get a brick fireplace as hot as possible - showed that the temp of the outside wall continued to increase for 9-12 hours! Since the typical chimney fire would probably burn for 5-30 minutes, it would seem near impossible for all that heat to transfer through tons of masonry.....and keep in mind that the testing was done INSIDE a lab. An exterior fireplace would be harder to heat up!

All bets are off when the fireplace is completely defective, etc.

But, all in all, the best defense against chimney fires is a good offense....clean burning stoves, seasoned wood, proper installation, etc.

My guess would be that the single largest danger from most chimney fires is the stuff coming out the top - catching something on fire. Of course, they also can ruin the chimney, but at least that is contained.

 

[MarcM]

If a stove is tightly installed, it is very difficult for a chimney fire to get enough air (if the stove air inlet is closed) to really cook!

And, open fireplaces don't tend to build up vast creosote deposits. Also, our chimney sweeps (at the shop) report that most post-epa stoves have very little (if any) combustible creosote in the chimneys.

So I assume most of these fires are with improperly installed old smoke dragons? As hopefully our resident combustion engineer, T, can verify - without a fairly vast amount of "feed" air, a fire can only get to a certain level.

In my experience with my father's most recent stove, a cat VC Encore, as long as you burn seasoned wood, there is almost never any creosote production. I help him sweep it three or four times a year, and there's never anything there.

You're quite right about the required oxygen to sustain the combustion of a chimney fire. The one's that get going, in my experience, are from very old and leaky installations, or something the homeowner does, for example, try to extinguish from below and opening the stove or cleanout, etc. Depending on the chimney, however, there can be quite a lot of availalbe oxygen in the ashpit even on newer houses. And it just so happens that the homeowners who are generally ill informed enough to burn wet/soft wood and/or burn at low temperatures often are usually the ones that don't know how to react to a chimney fire and end up doing something I described above.

 

[Heat Miser]

Heat Miser: How much does the small Tri-Max unit cost?

They're expensive. Just over $1000. Running a forge as a hobby (I like trying to make knives) there are a lot of fire risks. The forge, the oil quench, etc. Everyone I know who makes knives at one point or another has had an "incident" of some type with fire (not me, yet, knock on wood). I felt better spending the money than risking losing my entire shop if something goes wrong.