What's the best way to burn wood with the LEAST amount of creosote?

[NewtownPA]

I'm relatively new to the wood stove. I've been reading about creosote and chimney fires. What is the best way to burn your wood so that the chimney accumulates the LEAST amount of creosote? Also is it helpful to light a really hot fire every couple of days?

 

[Roospike]

What kind of woodstove ?

 

[NewtownPA]

It's an Avalon Rainier. Only a few years old (previous owners installed it)

Also what do you think about "stovepipe thermometers"?

 

[Eric Johnson]

As a general rule, it's best to make small, hot fires. It's also very important to burn dry wood, if you have any.

The very hot fire occasionally approach could result in a chimney fire, depending on how much creosote has accumulated in the meantime between hot fires. By making small, hot fires, you basically burn off any creosote before it has a chance to accumulate.

Let Roo know what kind of stove you have, and I'll bet he comes up with some specific suggestions.

 

[Gunner]

Dry wood and active secondary combustion.

If it weren't for stovepipe thermo's what the heck would we talk about here?

I have one on the stove top and one probe type in my doublewall, they are handy.

 

[Roospike]

stovepipe thermometers are good to check on things but for me its a lot better to run the stove as to make sure the wood is burning correct and I'm getting the heat i need. Now if you have a stove that is too small or running it at max all the time then yes your going to need a stove/ stovepipe thermometer.
Make sure your wood is well seasoned and dry , make sure you get a good coal bed before "loading" the stove with a lot of wood , make sure your wood is well chared before shutting down the fire for a long burn.

After a wile one gets the hang of it quick , the stove teaches you how you run her .

 

[tradergordo]

At the sake of possibly overlooking the obvious - when was the last time the chimney was swept/inspected? That's the first thing I would want to do for safety sake. After that, yes, I do like the idea of regular hot fires, they also sell creosote removal products which I've been told are very effective although I can't personally vouch for them. This was my first season burning, and a new chimney, and I've already swept the chimney twice - how else would I know how much creosote is forming? I will clean it again at the end of the season. There was very little build up found in the first two cleanings, but I wouldn't have known that without actually doing the sweep. In the future I might just sweep it once a year.


p.s. Personally I think a probe thermometer in the flue is essential equipment.

 

[NewtownPA]

At the sake of possibly overlooking the obvious - when was the last time the chimney was swept/inspected? That's the first thing I would want to do for safety sake. After that, yes, I do like the idea of regular hot fires, they also sell creosote removal products which I've been told are very effective although I can't personally vouch for them. This was my first season burning, and a new chimney, and I've already swept the chimney twice - how else would I know how much creosote is forming? I will clean it again at the end of the season. There was very little build up found in the first two cleanings, but I wouldn't have known that without actually doing the sweep. In the future I might just sweep it once a year.


p.s. Personally I think a probe thermometer in the flue is essential equipment.

The chimney was cleaned in December 2005 (just over one year ago). It's had 3 cords of wood burnt in it since then.

What is the purpose of knowing the flue temp?

(PS, I dated a girl from Phoenixville once. She went to a Christian Universty there (forgot the name). I noticed your avatar with the tree - cool! )

 

[Roospike]

I'm relatively new to the wood stove. I've been reading about creosote and chimney fires. What is the best way to burn your wood so that the chimney accumulates the LEAST amount of creosote? Also is it helpful to light a really hot fire every couple of days?

NewtownPA , are you having creosote issues in your stove , stove pipe , chimney and or chimney cap to ask the question ?

 

[NewtownPA]

I'm relatively new to the wood stove. I've been reading about creosote and chimney fires. What is the best way to burn your wood so that the chimney accumulates the LEAST amount of creosote? Also is it helpful to light a really hot fire every couple of days?

NewtownPA , are you having creosote issues in your stove , stove pipe , chimney and or chimney cap to ask the question ?

No, (not as far as I know) but I was reading about chimney fires, and I don't want to have one. I get vertigo so it's hard for me to be on the roof to look into the chimney.

 

[Roospike]

So with that said you must have a professional chimney sweep come out every year to clean / sweep your chimney ?

What is the make of your chimney ?

 

[tradergordo]

What is the purpose of knowing the flue temp?

Creosote forms when the exhaust from your stove is too cool. You won't know if its too cool unless you measure it! Now I know the next question is what temp is too cool - that can be a tough question, a lot depends on outside temp and the particulars of your chimney (how long, what its made of, how much is inside vs. outside, etc.) But a general rule of thumb that I've heard is that creosote will form quicky when flue temp is below 400, most of it will form where the chimney exits the house (the exhaust gas is rapidly cooled at that spot). Burning dry wood, and burning hot, will prevent creosote buildup, burning REALLY hot will burn creosote buildup right out of the chimney (i.e. a chimney fire - which used to be recommended, not so much anymore, so jury is kind of out on that today).

At any rate, if your exhaust gas isn't hot during the main burn phase of your fires, then your secondary combustion isn't active, which means you are not properly operating your stove (which is not only dangerous, but also an annoyance to anyone that is breathing your smoke). So the probe thermometer can be used as an indicator of proper stove operation. I don't really know the figures for other stoves, but with mine the flue gasses generally have to be over 500 for secondary combustion to be taking place, but often it runs closer to 800, and can go as high as 1000 without overfiring. 1000 is also enough to burn out any creosote in my chimney. Those figures are all specific to my own stove though, yours could be different.

You can find almost any stove manual online these days, if you do not have a copy of yours, I would get a copy and read it:
(broken link removed to http://www.avalonstoves.com/tween.asp?pdf=100-01140.pdf)

 

[NewtownPA]

So with that said you must have a professional chimney sweep come out every year to clean / sweep your chimney ?

What is the make of your chimney ?

Yeah that's what I was thinking... a "pro"fessional...

I have no idea what make my chimney is, unfortunately.

 

[Highbeam]

My approach is to keep the stove top above 350-400 and to keep the exhaust as clear as possible. Most of the time the stove is 500 or so and the exhaust is totally clear. That seems to be the best situation for minimizing creosote. Wet wood cools the stove and smokes the exhuast so you know you're doing something wrong.

Some sources say to sweep the chimney every 2 cords and some say once per year. I am just about 2 months into a clean chimney and have only checked once and cleaned out the nasty spark arrestor screen of the rain cap.

I have no exposed flue so no flue gas thermometer and I have no choice but to deem it as a useless piece of equipment. Honestly though, if I had an exposed pipe I would want to know the temps in the pipe and on the stovetop. That's the nerd in me.

 

[NewtownPA]

When I burn wood it's only smokey for a few minutes. I let the wood catch fire for about 5 minutes then reduce the air and when it's mostly coals on the outside of the log I reduce the air even more. I checked and I don't often have smoke coming out the chimney. I assume that's the way it's supposed to be, right?

 

[Eric Johnson]

Sounds like you're OK NPA. If you start to get creosote forming in the firebox (you can see it and sometimes it glues the door gasket to the body of the stove), or if you get a face full of smoke when you open the door, then there's a good chance your chimney is getting clogged up.

You should have the chimney inspected and/or cleaned at the beginning of each heating season. More often if you start having problems.

Do you have a stainless steel chimney or a masonry one?

 

[Rob From Wisconsin]

What is the purpose of knowing the flue temp?

Creosote forms when the exhaust from your stove is too cool. You won't know if its too cool unless you measure it! Now I know the next question is what temp is too cool - that can be a tough question, a lot depends on outside temp and the particulars of your chimney (how long, what its made of, how much is inside vs. outside, etc.) But a general rule of thumb that I've heard is that creosote will form quicky when flue temp is below 400, most of it will form where the chimney exits the house (the exhaust gas is rapidly cooled at that spot). Burning dry wood, and burning hot, will prevent creosote buildup, burning REALLY hot will burn creosote buildup right out of the chimney (i.e. a chimney fire - which used to be recommended, not so much anymore, so jury is kind of out on that today).

At any rate, if your exhaust gas isn't hot during the main burn phase of your fires, then your secondary combustion isn't active, which means you are not properly operating your stove (which is not only dangerous, but also an annoyance to anyone that is breathing your smoke). So the probe thermometer can be used as an indicator of proper stove operation. I don't really know the figures for other stoves, but with mine the flue gasses generally have to be over 500 for secondary combustion to be taking place, but often it runs closer to 800, and can go as high as 1000 without overfiring. 1000 is also enough to burn out any creosote in my chimney. Those figures are all specific to my own stove though, yours could be different.

You can find almost any stove manual online these days, if you do not have a copy of yours, I would get a copy and read it:
(broken link removed to http://www.avalonstoves.com/tween.asp?pdf=100-01140.pdf)

Interesting....
I just recently put a flue thermometer on our unit.
Our stove is a very small cast-iron unit (about a 1 cubic ft firebox). It doesn't take a lot to get it into
the "firestorm" mode (secondary combustion), but even with the most raging fire we are lucky
to get the flue thermometer over 600 degs. Could this have something to do with stove size, or
is my thermometer located too far up (about 2' above stove), or is the thermometer just
plain "whacky"??

Rob

 

[tradergordo]

What is the purpose of knowing the flue temp?

Creosote forms when the exhaust from your stove is too cool. You won't know if its too cool unless you measure it! Now I know the next question is what temp is too cool - that can be a tough question, a lot depends on outside temp and the particulars of your chimney (how long, what its made of, how much is inside vs. outside, etc.) But a general rule of thumb that I've heard is that creosote will form quicky when flue temp is below 400, most of it will form where the chimney exits the house (the exhaust gas is rapidly cooled at that spot). Burning dry wood, and burning hot, will prevent creosote buildup, burning REALLY hot will burn creosote buildup right out of the chimney (i.e. a chimney fire - which used to be recommended, not so much anymore, so jury is kind of out on that today).

At any rate, if your exhaust gas isn't hot during the main burn phase of your fires, then your secondary combustion isn't active, which means you are not properly operating your stove (which is not only dangerous, but also an annoyance to anyone that is breathing your smoke). So the probe thermometer can be used as an indicator of proper stove operation. I don't really know the figures for other stoves, but with mine the flue gasses generally have to be over 500 for secondary combustion to be taking place, but often it runs closer to 800, and can go as high as 1000 without overfiring. 1000 is also enough to burn out any creosote in my chimney. Those figures are all specific to my own stove though, yours could be different.

You can find almost any stove manual online these days, if you do not have a copy of yours, I would get a copy and read it:
(broken link removed to http://www.avalonstoves.com/tween.asp?pdf=100-01140.pdf)

Interesting....
I just recently put a flue thermometer on our unit.
Our stove is a very small cast-iron unit (about a 1 cubic ft firebox). It doesn't take a lot to get it into
the "firestorm" mode (secondary combustion), but even with the most raging fire we are lucky
to get the flue thermometer over 600 degs. Could this have something to do with stove size, or
is my thermometer located too far up (about 2' above stove), or is the thermometer just
plain "whacky"??

Rob

Rob - I think EVERYTHING you mentioned is a factor. 2 feet is high, quite a bit higher than mine (and mine is actually a bit low, I believe 14 inches) so that's going to make a difference, and of course the smaller fire will make a big difference. Also, how accurate the thermometer is will make a difference - you don't know unless you calibrate it, and even the best brands state a 5-10% margin of error, also the probe positioning will make a difference, if it passes though the dead center of the flue its going to have a slightly higher reading than if it doesn't, and flue diameter will also be a factor (mine is 6" which is going to give higher reading than 8"), as well as the gauge of the steel (my flue is 22 guage, which also results in slightly higher readings than the more typical thinner flue).

 

[Hogwildz]

When I burn wood it's only smokey for a few minutes. I let the wood catch fire for about 5 minutes then reduce the air and when it's mostly coals on the outside of the log I reduce the air even more. I checked and I don't often have smoke coming out the chimney. I assume that's the way it's supposed to be, right?

5 minutes? Seems a lil short to me. I let mine go around 15 mins. then another 10-15 on 25%, thn whe its good and hot & charred shut the air down. 5 mins seems very short. Are you getting a good secondary burn after cutting her back at 5 mins?

 

[DriftWood]

#1 thing get your chimney swept on a regular basis. Watch your chimney cap for smoke and buildup. Burn dry seasoned fire wood at least one calendar year old split and stacked. Two year old wood is better. Let wet seasoned wood {rain soaked or snow covered wood} dry before using it. Keep your flue temps hot and not visible smoke coming out your chimney cap.

 

[pistonslap]

I don't know how much faith I have in the stovepipe thermometers. I have a condar surface mount on my single wall flue pipe. I have had under 270 f. readings on the guage and not a trace of smoke coming out of the chimney. I try to run it up to 600 to 700 f. once a day for no longer than 20 to 30 min. Although not what I intended, I pretty much use it more as an overfire precaution than a creosote forming guage. Being afraid of heights, I get out my binoculars and try to keep an eye on the chimney cap.

 

[NewtownPA]

Sounds like you're OK NPA. If you start to get creosote forming in the firebox (you can see it and sometimes it glues the door gasket to the body of the stove), or if you get a face full of smoke when you open the door, then there's a good chance your chimney is getting clogged up.

You should have the chimney inspected and/or cleaned at the beginning of each heating season. More often if you start having problems.

Do you have a stainless steel chimney or a masonry one?

The actual firebox is very clean. I have never had my door glued. On occasion (if I put in 3 or 4 logs on top of a bed of HOT coals and close the door and shut the air to minimum) I will have a black coating on the glass. I use a razorblade to scrape it off the next morning. By the way, should I be doing that (putting fresh wood on top of the coals and shutting the air to minimum right away)?

Thanks so much for everyone's help. I'm still learning here.

 

[NewtownPA]

When I burn wood it's only smokey for a few minutes. I let the wood catch fire for about 5 minutes then reduce the air and when it's mostly coals on the outside of the log I reduce the air even more. I checked and I don't often have smoke coming out the chimney. I assume that's the way it's supposed to be, right?

5 minutes? Seems a lil short to me. I let mine go around 15 mins. then another 10-15 on 25%, thn whe its good and hot & charred shut the air down. 5 mins seems very short. Are you getting a good secondary burn after cutting her back at 5 mins?

Thanks. I just took a guess when I said "5 minutes". Next time I'll actually time it to see how long it really is.

 

[NewtownPA]

By the way, I"m not really sure what "secondary burn" is. Could someone explain it to me? (I *think* it means when I get those jets of combustion from the rear air tubes... I'm not sure though).

 

[Gunner]

By the way, I"m not really sure what "secondary burn" is. Could someone explain it to me? (I *think* it means when I get those jets of combustion from the rear air tubes... I'm not sure though).

Correct

BB did a nice write up once...don't know where it is tho.