Creosote fire!....

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Cat stoves are an even better example. Who needs a "hot fire once a day" when 1600 degree exhaust has been blasting out of that cat all night? ;lol

Just out of curiosity, are there any good cat furnaces that could be hooked into duct work? I'm running hitzer which isn't nearly as technologically advanced, though I do like it. The whole cat thing is very interesting to me but I'm not sure how well it would work into my current setup.
 
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Not sure about that one. I think in the future we are going to be seeing more and more cat stoves on the market though.

EDIT: BB types faster than I do.
 
EPA cert furnaces are in the near future, we (the industry) are awaiting the government to give us guidance on the parameters we will have to meet. once we have the requirements , we'll develop the products to meet them.

personally im excited to see what we will need to achieve. i know looking at what we have been able to develop due to phase 2 (our industry as a whole) i expect we'll be able to produce products with similar jumps in technology.

IMHO the whole house add on furnace has been overlooked too long, but we(again, the industry) aren't going to develop a new type furnace until we have an idea on what we have to do as far as emissions. it simply costs too much to develop a unit or especially a line of products, then find out soon after that we cant sell it.
 
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Hope I am still around for it Mike. That basement flue right next to the back door has been waiting for ya to do the thing since 1985. >>
 
They haven't been selling the furnaces very long. Couple of years I believe. But they have been making things that toast trees for a really long time so I bet the thing is a good one.

Gasifier's are probably close to as clean and efficient.
 
Read Pens post again. His quoted temp was for a single wall surface reading. Your double wall (probe) reading is a different critter. I often take my double wall pipe (with probe thermo) to 800F.

ETA: I am with BroB on the flame impingement. Also the location of the gunk will make a big difference. The gunk stuck at the top 3 ft of your pipe will take much more heat (stove heat) to light off than a pile of gunk in a 90 degree elbow 4 ft from the stove body.

Yes. I am by no means an expert. I just started burning in an epa stove about a month ago but I start crossing around 800 (double wall probe temp) on every load. Wait, now I wonder if that is too high. Should I be throttling down the damper earlier?
 
I stand corrected.


spinny, this is the real beauty of this community, when information which may not be current is seen, its corrected in a civil way. nobody gets blasted in here. the mission is to educate.

a lot of old traditional "methods" simply do not apply with the newer technology , as well as the proper practices in burning wood for heat.

the "toss a green split on cause it burns all night" for instance. green wood will not burn, however if green wood is added to an existing fire, the existing fire will "cook" the moisture out of the wood and eventually when its been "dried" it will start to burn. problem is, in order to "dry" this green split, a lot of thermal energy is wasted. this is heat energy used inside the stove to dry out the green stuff instead of being used to radiate to the structure.

a little physics folks, moisture is the enemy of woodburning. this is why in laymans terms, to remove the water it would have to be cooked out by heat. this water once it has absorbed enough thermal energy it will flash to steam through evaporation, as this steam dissipates away from the fire it carries this thermal energy with it.. its a physical fact that heat (thermal energy)cannot be destroyed, only dissipated so by carrying this heat out of the stove with the steam we are doing just that,

"evaporation" is a cooling function. same as perspiration in our own bodies, the heat is removed from us by the vapor which by turning to vapor carries the heat energy away from our bodies.

now, understand that since the steam has left the fire it starts cooling in the flue, if this vapor drops below 211F it condenses back into a liquid and starts coating the flue like dew on your windshield, as it builds up and gravity starts drawing the water back down it gets closer to the fire and warms again, if it gets warmed back to 213F it evaporates again (remember its a cooling function, its drawing heat with it to dissipate again higher in the flue) this cycle builds "wet creosote" which is the stuff of flue fires.

burning a "hot fire" to clear the flue , is literally asking for a flue fire when the flue has been coated in the above manner. there are many a flue liner that's suffered cracked tiles from repeated firings due to this practice. and once a flue tile has been cracked , the heat is able to attack the structure of the chimney itself (and possibly the wood structure of the house which would be protected by the cracked tile). this causes house fires even when a flue fire is not happening at the time the house goes up. it happens when the chimney itself cracks and heat has an entry into the wood behind it.

ask my firefighting friends in here about this, they will confirm it im sure. bear in mind also that im not trying to "one up" the poster above , merely to post information describing the situation in a way that is educational.
 
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Yes. I am by no means an expert. I just started burning in an epa stove about a month ago but I start crossing around 800 (double wall probe temp) on every load. Wait, now I wonder if that is too high. Should I be throttling down the damper earlier?

If your burns times are not shorter than expected, then I wouldn't be that concerned but it never hurts to experiment a bit and try turning things down just a bit sooner and see what you get.
 
If your burns times are not shorter than expected, then I wouldn't be that concerned but it never hurts to experiment a bit and try turning things down just a bit sooner and see what you get.
Good point. I am not getting very long burn times but I also haven't really loaded her up to the gills yet either. That coupled with the small firebox size, I thought the burn times were normal so far. I will def try turning things down a bit sooner. Thanks for the advice.
 
Yes. I am by no means an expert. I just started burning in an epa stove about a month ago but I start crossing around 800 (double wall probe temp) on every load. Wait, now I wonder if that is too high. Should I be throttling down the damper earlier?


if you are reading with a probe 800 isnt too terribly high remember this would equate to about 400-450 or so with a single wall surface thermometer. i used to run a probe in my flue 18 inches up from my stove when i was running my cat stove and it literally mirrored my cat temps (which i used to see 1000F routinely)

you could throttle back a bit sooner but in a "noncat" this tends to intensify the secondaries provided they are lit up and singing. big thing i look for is when you throttle back early, look to se if the secondaries light off quickly as the primary air is reduced, they should , if not then you are too early, you can open the primary back up and let it go a bit longer in that case. you wont soot your chimney that fast. BTW that napoleon is a fine stove.
 
Hope I am still around for it Mike. That basement flue right next to the back door has been waiting for ya to do the thing since 1985. >>


i've actually done a couple concept drawings, thinking on basing on the same tube tech we use in the 30, longer rolling run across the top may have to split the secondaries though , not sure without building it if i can carry the secondary air all the way to the front. (gonna be fun playing with it)
 
I came within an inch of bringing that ESW furnace at Rice Hardware home for $750 in 1985. Was concerned what it would do to that new heat pump. The heat pump that died from lack of use for heat or A/C in the nineties. :confused:

Can't really complain. Old Brownie got the job done. Now new Brownie is.
 
Yes. I am by no means an expert. I just started burning in an epa stove about a month ago but I start crossing around 800 (double wall probe temp) on every load. Wait, now I wonder if that is too high. Should I be throttling down the damper earlier?

FWIW I sometimes run up to @850 deg or even a bit higher on startup before I dial it back. Cruises between 450 and 600 depending on how/what I loaded, how far i shut the auir down, etc. An Osburn flue probe shows 450 through 950 as the "safe" zone.
 
BTW that napoleon is a fine stove.


Are you being serious about that? Coming from a competitor, I'm not sure. We like it. Really like the looks. Our is the porcelain brown finish which we really like. Got it for $700 used. Wasn't too day it is 6 years old, but can't remember for sure.
 
spinny, this is the real beauty of this community, when information which may not be current is seen, its corrected in a civil way. nobody gets blasted in here. the mission is to educate.

a lot of old traditional "methods" simply do not apply with the newer technology , as well as the proper practices in burning wood for heat.

the "toss a green split on cause it burns all night" for instance. green wood will not burn, however if green wood is added to an existing fire, the existing fire will "cook" the moisture out of the wood and eventually when its been "dried" it will start to burn. problem is, in order to "dry" this green split, a lot of thermal energy is wasted. this is heat energy used inside the stove to dry out the green stuff instead of being used to radiate to the structure.

a little physics folks, moisture is the enemy of woodburning. this is why in laymans terms, to remove the water it would have to be cooked out by heat. this water once it has absorbed enough thermal energy it will flash to steam through evaporation, as this steam dissipates away from the fire it carries this thermal energy with it.. its a physical fact that heat (thermal energy)cannot be destroyed, only dissipated so by carrying this heat out of the stove with the steam we are doing just that,

"evaporation" is a cooling function. same as perspiration in our own bodies, the heat is removed from us by the vapor which by turning to vapor carries the heat energy away from our bodies.

now, understand that since the steam has left the fire it starts cooling in the flue, if this vapor drops below 211F it condenses back into a liquid and starts coating the flue like dew on your windshield, as it builds up and gravity starts drawing the water back down it gets closer to the fire and warms again, if it gets warmed back to 213F it evaporates again (remember its a cooling function, its drawing heat with it to dissipate again higher in the flue) this cycle builds "wet creosote" which is the stuff of flue fires.

burning a "hot fire" to clear the flue , is literally asking for a flue fire when the flue has been coated in the above manner. there are many a flue liner that's suffered cracked tiles from repeated firings due to this practice. and once a flue tile has been cracked , the heat is able to attack the structure of the chimney itself (and possibly the wood structure of the house which would be protected by the cracked tile). this causes house fires even when a flue fire is not happening at the time the house goes up. it happens when the chimney itself cracks and heat has an entry into the wood behind it.

ask my firefighting friends in here about this, they will confirm it im sure. bear in mind also that im not trying to "one up" the poster above , merely to post information describing the situation in a way that is educational.

I appreciate the information. There is a lot of really good information there.

I understand all the preventative measures that need to be taken to prevent any creosote buildup. I think that the idea behind burning hot once a day is to remove the moisture that you are talking about that may be building up if the stove is not operating in an ideal way (burning hot enough). That is just the way I understood (past tense) it. Thanks for the info.
 
Better advice is not to smolder the fire at any time, flue temp monitoring is the key to clean burning , older stoves more so.
Burning your stove hot once a day tends to indicate you are burning it too low the rest of the time.
 
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Better advice is not to smolder the fire at any time, flue temp monitoring is the key to clean burning , older stoves more so.
Burning your stove hot once a day tends to indicate you are burning it too low the rest of the time.

My "problem" is my house is really well insulated. For me to have it burning and keep the flue temp at an ideal temp I have to keep a very small shim under one side of the damper (1/16") so that it doesn't smolder when my thermostat isn't calling for air which raises the damper. If the outside temp is above 30 degrees it warms the house up to much and I feel like I'm waisting wood. I am getting it figured out and dialed in, it just takes some tweeking. I've been just using less wood and filling 3 times per day instead of 2. Its amazing the difference good insulation makes.

The high here next Tuesday is 13 degree so it will be interesting to see how it performs in colder weather. I know I'm looking forward to going home to that warmth.

It probably doesn't help that my wood was cut last winter. It has had almost a year to season but it could be drier.
 
Yes. I am by no means an expert. I just started burning in an epa stove about a month ago but I start crossing around 800 (double wall probe temp) on every load. Wait, now I wonder if that is too high. Should I be throttling down the damper earlier?

You are doing fine. 800F (probe) is not out of line. I personally do it to get a set (known) draft established that I can base my stove adjustments off of. A "set point", if you will.
 
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You are doing fine. 800F (probe) is not out of line. I personally do it to get a set (known) draft established that I can base my stove adjustments off of. A "set point", if you will.
Thanks. Yes I get it up to that temp mainly to establish draft.
 
Hmm, well I've only been bringing my non-cat stove temp probe up to between 400-550F. 800F seems real hot, but I assume it's ok. If I am using good dry wood and typically cruising 400-550F, am I building creosote?
 
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