Sunday, November 16, 2008


We just spent a couple hours dealing with a chimney fire.  Had a fair amount of time to think about stuff, while watching various portions of the stove, and stovepipe, glowing cherry-red.

Chimney fires are a fact of life.  If you burn wood- you will have fires, in your chimney, at some point.  

There are quite a few folks who will sell you stuff, and services, to "ensure" that you will never have to cope with a chimney fire.

The reality remains- if you burn wood- someday, you WILL have to cope with a fire in your chimney.  It's probably a good idea to know that- be ready for it, physically and mentally- so you're able to respond, when the time comes.

Metaphor alert.  

A whole bunch of this train of thought is applicable to - your entire life, and world.

I know plenty of people who are terrified of chimney fires, and go to great lengths to prevent them.  That's fine.  Maybe.  Maybe not.

I work on the other end of the spectrum- like most hillbillies from days gone by, I SET my chimney on fire, regularly.  So the fires are manageable, and non-catastrophic.

The one today was semi-planned; I knew the chimney needed a good burn, and when I dumped a whole pile of used nose-blowing tissue into it (we're still fighting the sinus bug from hell) - the chimney started to give the little warning signs that it was hot, starting to burn, and could go all the way if I encouraged it.  So I did, indeed, encourage the fire- gave it a little more heat from crumpled newspaper and old cardboard; opened up the flues to let the draft rip- and got a good fast burn going.

The problem with taking measures to "be sure" a fire never happens is:  some day - some day - you will have a fire anyway.  Either your measures will stop working.  Or you'll get old, and forget, just once, to have the chimney swept on time.  Or - something in the fire will be different, a little more creosote will form this cycle, or the fuel will burn a little hotter- and -

Presto.   Big fire in the chimney.  And you're not used to dealing with it.

Metaphor #1- gosh, it's called "California".

“It was a firestorm,” Captain Ruda said. “There were 50-foot-length flames streaking across the mobile home park. Fire hoses were melting into the cement and concrete. That’s how hot it was.”

For decades- we've suppressed fire in those areas.  Made them "fire proof", and "controllable".  Built houses, cities.  Sure, there was always a little fire danger, but hey, all you have to do is be careful, right?  And take proper precautions.

Turns out- not.  Nature's original answer for fires here?  Fires.  On a regular basis.  Stop them, and- eventually, all hell breaks loose.


Back to my own chimney fire.  It turned out to be more of a fire than I'd counted on.

No disasters; the Little House is intact.  But there could have been- if I hadn't been used to dealing with chimney fires.

First thing to know about chimney fires- if you've got one; you have to WATCH IT- every second- until it's out.  Really really out.  

Ok, some basics:  chimneys catch on fire because wood burns inconsistently (no matter what you do, or what you burn) and wood is a very complex material, with fractions that vaporize at wildly differing temperatures.  And condense again, at wildly differing temperatures.

The Owners Manual that comes with your spiffy new state of the art woodstove says: "When starting your fire, be sure to let the fire burn as hot as possible for the first half hour, to ensure that the chimney is properly heated, and to decrease creosote build-up.  Burning fires 'cool', with a cool stack, will greatly increase the risk of chimney fires."  Sure will.

The thing is- you are going to have SOME creosote deposited in your chimney, no matter how meticulous you are about getting the stack hot.  It will happen.  When you put a new piece of wood in- is it hot?  No.  Does it all start to burn at exactly the same time?  Nope.  One end of the log is a little further from the core of the fire- and rather than burning- "stuff" in the wood vaporizes, and blows up the stack- which, regardless of your efforts, is cooler than the firebox.  Some of those gasses will condense out of the smoke- bingo; creosote build up.  Guaranteed.

Lots of things influence how fast the gunk builds up- what kind of wood you burn; whether it was really "seasoned" before you burned it, or was "a little green" ; how cold the weather is (if it's not too cold, the tendency is to burn a cooler fire= more creosote); who in the family has been chief fire regulator recently (holding my tongue); etc.

The gunk will build up.  There is no way around it.

In the specific case of my present fire- gunk had built up in a place I'd never thought of before, inside the stove.  And this time- it caught fire.

I can't tell you the name of our wood stove- I can't remember it, and it isn't written all over it like most models.  We bought it through our Amish neighbors- it's made in Canada, by a Mennonite community.  A great stove, really; uses about 1/3 of the wood that our much older US made stove that was designed and built in the 1920's did.  This one is designed both to cook on, and heat with; the firebox is much bigger than kitchen stoves usually come with.

Not that it's perfect.  It's advertised as "airtight" - but that's a pretty big fib; there are a bunch of air-leaks connected to the oven doors; cannot be sealed, and make it impossible to truly operate it as an airtight stove.

The cause of this weird fire - there's a water reservoir built in; a 5 gallon tank with one side in the combustion gas stream.  Somebody - decided it would heat the water faster if they put a moveable baffle right next to the tank, so that you can direct the stack gases to run under the tank, as well as next to it.  Yup, it heats the water faster.  It also- very very slowly- accumulates creosote.

So I was pretty astonished when, as I was watching my chimney fire cool down, I started to see my water tank (with water in it, of course)  smoke, and see blue flames coming from underneath the water tank.

That was not cool.

But at least I was watching; and saw it start to happen.  And was not scared out my mind by this horrifying danger.  

If you burn your chimney on a regular basis, it's not too hard to control.  Fire needs- fuel, heat, and oxygen.  If you decrease the supply of any of those, the fire has to slow down.  If you cut one off completely, the fire will go out.  Closing all the dampers slows the air flow- if your stove is actually airtight, you can cut the air off completely.

Or you can add water.  Dumping water on your hot stove, or into the hot firebox- is NOT recommended; you can warp the iron, or crack the firebrick.  But- as a 2nd resort, a little water, sprayed onto the fire from a spray bottle- can cool and slow a fire.

Last resort?  Your fire extinguisher; sprayed right into the firebox, and up the chimney.  Makes a mess, but it will do the job.  You DO have a fire extinguisher, I know- right handy to the stove.  Of course you do.  You'd be a fool not to.

I had my spray bottle right there- but the weird location of the creosote made it impossible to get at.  Mostly I had to just spray near by, and keep the fire from getting too hot.

It worked.  Burned out- boy, it's nice and clean under there now.  I guess we have a "self cleaning oven" after all.

A normal, planned chimney fire is a half hour job.  One person stays at the stove, opening and closing drafts to keep the fire from getting too hot (or going out too soon; as long as this fire is going, we'd like it to clean out the chimney.)  One person stays upstairs, watching the stove pipe where it goes through the bedroom- it will usually get some red spots.  If the red starts to move to yellow- you need to cool the fire.  If it turns towards white- you've got trouble; that's when you can melt steel stove pipe- and set a fire that will burn the house down.  If closing the drafts and air on the stove doesn't cool a yellow spot to red quickly- start reaching for the fire extinguisher.

The house will get stinky from the extremely hot stove and pipe- open the windows.  In a half hour- it's over, the stove is drawing much better, burning much more efficiently, and you're safe from chimney fires for a couple weeks, at least; maybe a couple months.

This fire took us two hours- the gunk inside the stove caught, set on fire by burning chunks of creosote dropping down the chimney, and couldn't be extinguished.  It warped the inside of the oven a bit; and we just had to let it burn out.

Bad design, I'd have to say.  Basically, there is no way to clean that part of the stove- and no access to it in case of a problem, either.  The design needs to be changed, to make it safe.


Which leads me to the title for this post: "Foolproof".

We spend a lot of time making machines, and processes, foolproof, in our present society.  Safe.  Really, really safe.

I remember the startling realization when I was learning German that their word "idiotensicher" - does not, in fact, translate exactly as "fool proof".  Though that's what the dictionaries say.  It's not what they mean.

An idiot is NOT a fool; it's different.  And "secure" is not the same as "proof", either.

Both interesting, and related, concepts; but not identical.  Made me start thinking.  For one thing, it made it clear to me that German is not English with different words- there's a lot of stuff that just will never translate; the core cultures are different.

Another thing I know from my own business; as I have proven many times, in trying to develop "instructions" for customers.

If you make a process foolproof; Nature will quickly make a better fool.

You can see how well it's worked to make our economy "foolproof".  All the time and effort and legislation spent on making processes safe.


Looking ahead to our new world: one thing that worries me is our current supply of fools.

We're over-supplied; I think that's clear.

It might be useful to blame Ralph Nader.  

All of the efforts to make the world a little safer for those who are a little careless-  may not be turning out so well.  An awful lot of people who would have been self-eliminated, in the old days; have lived on; and reproduced.

My woodstove would have burned the house down today, if I hadn't been on guard.

If you are a real Laura Ingalls Wilder fan, you've read "The First Four Years" - the continued story of the first four years of married life for Laura and Almanzo.

He built her a house.  She burned it down.  Somehow- she hadn't learned well enough, not to allow flammable materials to build up around the stove.  One spark is all it takes.  You keep a pile of newspapers handy right by the stove for lighting it in the morning?  Bad idea.  No kidding.  No, really.  You must not do that.  Ever.  Don't.  Just this once, for a few minutes, is ok, though, right?  No.

The world is now full of people for whom "not ever" is an approximate statement, not an absolute.  The chimney fire that will burn them out of our stove pipe- is going to be very painful for all concerned.

Try to make sure the people you depend on have common sense.  Really.

There should be a Nobel Prize for Common Sense, don't you think?  And Depts. of Common Sense in the universities.  How is it they don't exist?  They would contribute far more to the well being of humanity than any Dept. of Economics.


Spice informs me that our stove is a "Gem Pac".  The closest thing to it listed is the 2020-W, though there are significant differences between current models and our 12 year old one.

In case anybody is interested; I'm convinced the evolution of the home wood cookstove is in a very primitive stage.  Most models out there have one or two nifty features- but then use the wrong materials- or skimp on construction, or something.  The wood stove that "has it all" - has not been made.  A business waiting to happen...


knutty knitter said...

I think I'll stick to electric - its cheaper and more environmentally friendly round here. There's only one coal fired plant in the whole country and even that is used mostly for backup.

Mind you it pays to be careful with that too. It can be just as idiot prone as fires are.

Hope your colds leave soon - ours stayed for a couple of weeks being carefully shared round along with a nasty tummy bug someone got from school.
That bug is a recurring one and we still haven't completely cleared it - I need to disinfect door handles, knobs and buttons again I think!

viv in nz

Anonymous said...

I *just* had a conversation about stove safety with a friend today. SHe has a safety gate surrounding her woodstove, and inside the gate in an ungodly jumble of paper, kindling, etc. You can hardly reach the srove for all the crap in the way. Someone else challenged her on the fire hazard, and she responded

"I'm a member of Mensa! I'm not an idiot. It hasn't burned down the house in the three years I've lived here. It's fine, and you don't know what you're talking about."

As a child, my mother used to lecture me about how "just because a person has a high IQ, does not make them particularly bright."

ISn't it funny how, decades later, mom was right about some things after all?

~J~ said...

fantastic post

Zabetha said...

Oh you have outdone yourself, wonderful writing! Long post but well worth it. My favourite line: "If you make a process foolproof; Nature will quickly make a better fool." Well said sir.

Keep on keepin' on!

Connie said...

phew, good you had it under control. Our stove still has to get plumbed, but then again we've used wood stoves all our lives. One does get complaicent at times.

We did get double wall pipe so I guess we won't know if we've got a chimmney fire.

feonixrift said...

I'm sitting here stuck indoors due to that "all hell breaks loose", which around here is more like "aw hell, not again..." Baton down the hatches, start the air filters, wait it out. Be glad my town uses goats. I don't think they're allowed to do prescribed burns this close to the city (yeah, uh, don't mind the logic, it's Cali), but at least the goats keep the brush somewhat under control.

I learned a new daftness the other day. The red fire retardant they drop from planes acts as a fertilizer after the fires have passed. On the surface this looks like it might be a good thing: More plant growth to hold the hills down. But wait! Extremely high fertilizers induce growth of annuals and other shallow-rooted stuff, at the expense of longer lasting scrub and small trees. So much for holding the soil down, and more fodder for the next fire.

This all reminds me of the phrase "no user serviceable parts". Lots of folks seem to run their whole lives as if that phrase applied. Just set it up, hit go, and complain when it stops. I've got a roomba - great gadget, by the way, if you like that kind of tech. It does a fabulous job of cleaning up the dust from regional fires, but best of all, it's trivial to disassemble. I can get at every little piece. People complain that its bearings die? Not if you clean them like you're supposed to! Funny, how maintenance has slipped out of the vocabulary.

Don't get me started, though, on people whose review of a water canteen contains phrases like "it's heavy when it's full of water".

Anonymous said...

glad your fire was contained!

ahh, foolproof.

apparently the accident statistics for anti-lock brakes are no better than regular brakes, and they think it's because people think they're invulnerable with anti-lock brakes, so they drive like it, including during snow and ice and heavy traffic.

and count how many newspaper stories say "we can't have another depression -- we learned from the last one so we're smarter now."


Hank Roberts said...


Cautionary tale:

"... I'm afraid of fools, and the chance that I have one working for me, here, affects me like having a cobra crawling around my bedroom in the dark. I want you to locate any who might be in a gang of new men I've had to hire, so that I can get rid of them."
* *
"And just how do you define the term 'fool', Mr. Melroy?" she asked. "Remember, it has no standard meaning. Republicans apply it to Democrats, and vice versa."

"Well, I apply it to people who do things without considering possible consequences. ... people who push buttons to see what'll happen, or turn valves and twiddle with dial-knobs because they have nothing else to do with their hands. Or shoot insulators off power lines to see if they can hit them. People who don't know it's loaded. People who think warning signs are purely ornamental. People who play practical jokes. People who--"


And for those of you in old houses, with gas-fired "floor heaters" -- a metal grill in the floor, a metal box under it; cold air falls down through the outside holes, goes under the baffle and rises up the inside over the heat exchanger (corrugated metal case inside which the gas flame lives).

Air that falls down carries dust; air that rises leaves it behind.

Old gas floor heaters build up about an inch of dust and cat fur and stuff through a spring-summer-fall. It felts (mats down) and gets thick and dense and new years make new layers.

Eventually it catches fire and burns your house down, because the flame comes up right through your floor alongside all that dry old wood.

Happens to a few people around where I live in N. Ca. every winter. Usually to old people living alone who've forgotten it, or had whoever did check it each fall die on them. Oh, there was one guy who didn't wonder what the floor grille was for when he moved in in the fall, so he piled boxes on it. A few months later, when it got cold, he turned on the heater switch, its little electric igniter lit the gas, the apartment warmed up, and then in the middle of the night his pile of boxes caught fire and killed him.

It ain't just creosote. It's nice fluffy little dust bunnies too.

Get out that flashlight. Look down into your floor heater or wall heater for that matter, anything that can collect dust. Got a nice new furnace? Checked the air filters yet? Checked _behind_ them?

jewishfarmer said...

Nice post, Greenpa. We've not had a chimney fire, but I rather expect one (rather like I expect the collapse of the economy - I'd rather not, but I'd rather not be unprepared).

And a good reminder to check the weird parts of my stove for goop


tjbbpgob said...

Anything advertised as "foolprof" just hasn't been tested by the right fool.

Hank Roberts said...

> wood stove

The SF Bay Area is just starting its winter months when there will be bans on burning wood during the windless cold damp inversion-layer periods -- during which more than half the particulates are from fireplace use and health problems abound for those with compromised breathing.

When designing it, add a really effective catalytic converter to that hypothetical wood stove, to recapture the heat from oxidizing the stuff that usually goes up the flue.

Hank Roberts said...

PS, an aside re

> fire retardant they drop from
> planes acts as a fertilizer
> after the fires have passed.

So does the mineral ash, the first year; European and Asian annuals are highly adapted to capture that with widespread shallow roots.

On my N. Ca. site we've tried spraying sugar water in places after burns, just before the snow falls, based on some ideas I got from researchers still using the old Usenet science newsgroups.

Here's something more recent on the same subject:

-- by springtime when the annuals germinate the soil can be back to its normal dearth of available minerals on the surface, giving the advantage back to the deep-rooted native perennials that aren't going to be poking much aboveground til later.

That last aerial tanker run should probably be sugar water, to accomplish the same thing on a useful scale.

Anonymous said...

Wow, great post -- I once again learned a bit more about how little I know. I don't have a wood stove yet but was thinking about one in the future -- never even thought about the cleaning of them.

Anonymous said...

Great post! We are in the process of getting a wood cook stove in our new house. I will remember this post for the future.


Omelay said...

nice blog.
i clean our chimney every year mechanically--brush and pole. usually very little creosote each time. although i don't try to heat water or use the chimney as a heat source. since our second year here we burn very seasoned wood. our chimney is insulated and most expansion/condensation happens after the chimney.

i liked your post because it portrayed a respect and need for close monitoring of a wood heat source. although i'd never try to set a chimney fire. my dad used to every so often also. i guess, i'd rather climb up on the roof, clean it manually and keep the illusion that it is safer that way.

btw, the gempac is a beautiful stove. my wife would be jealous.