Observations of An Ignoramus

[Ambull01]

Posted this on another site but wanted to see what you guys think. Seems like this site has a different opinion on most matters compared to the other site.


The ignoramus is myself. I'm totally new to wood burning. Just got a fireplace insert as a gift but have to wait until next year to use it.

Anyway, I've been mentioning I burn/will burn wood for heat to just about everyone I meet. I have met a few people that burn as well and found they all have not heard of secondary combustion. Father in-law has been burning at least 6 years and had no idea his free standing stove's catalytic converter was for secondaries. Brother in-law burned about 5 years and wasn't sure how creosote is formed. Other people I've spoken to were totally clueless. Is this normal? If it is, then every single member of this site is much more informed than your average wood burner.

Second thing. Since most of us are going through this little cold spell, people around me are heating like it's middle winter. I walk my dog twice a day and since I've become totally obsessed with wood burning/cutting I always look out for downed trees or chimney smoke. I've noticed mild to excessive smoke coming out of chimneys. So, if most people are clueless about wood burning, I assume this kind of smoke/fire burning is the norm. If it is the norm, why aren't chimney fires more common? I would like it would be a weekly occurrence.

Third thing. This has been keeping me up at night. My chimney's not lined which is why I'm holding off on burning this year. I'll install a SS liner and insulation next year which brings me to my question. How does the creosote eventually get hot enough to ignite? I ask this because the smoke leaving the stove will be hotter the closer you get to the fire. Creosote forms as this mixture cools off (I think that's right). Sooo, most of the creosote will form higher up the flue. The higher up you go, the amount of heat will drop. How does the creosote eventually get hot enough to ignite?

 

[chuckwood]

>Second thing. Since most of us are going through this little cold spell, people around me are heating like it's middle winter.

From my reading and understanding of the relationship between sunspot cycles, solar energy output, and the weather, the odds are we are entering a serious cooling phase that will affect all of us, most of it negative. I don't view it as a "little cold spell". Think of what January is going to be like if they've just got six feet of snow in western New York. A few scientists claim we are at the beginning of another major ice age. If so, we are facing a catastrophe.

>I always look out for downed trees.

Once you become a wood burner, you will always be on the lookout for fresh cut firewood piled up next to the street, ready for the first scrounger to load up and haul off. You'll be secretly happy when storms create blowdowns, as long as you don't suffer any damage at your own place. You'll buy a pickup truck or a trailer, and you'll be looking at the free firewood ads in Craigslist.

>why aren't chimney fires more common? I would like it would be a weekly occurrence.

I did my first chimney fire when I was a kid, starting a fire in the family fireplace. I would stuff a lot of newspapers up in the chimney and light them in order to get a good draft started before lighting up my kindling. This way I made a lot less smoke that got in the house when starting it up the kindling. When the chimney caught on fire, it started roaring like a jet engine and I could feel it sucking air. I got scared and didn't know exactly what was happening, but I had the presence of mind to shut the damper. This stopped the air flow and the chimney fire slowly went out. We later got a chimney sweep to clean and inspect the chimney for damage, everything was good, but the fire happened because we had been using the fireplace for years without having it cleaned.

About creosote, there is a liquid product containing manganese nitrate, it's available at wood heater stores. You spray the liquid into your heater on a daily basis, ten squirts or so. It makes the creosote less likely to stick and accumulate in your chimney. Since I've been using it, it's been a lot easier to clean the chimney.

 

[firebrick43]

As a mech at work says unfortunately about ignorance and stupidity. "They walk among us".

You sir by definition are not ignorant. You realize issues and are thinking about them and seeking the answer. That is intelligence in my book.

Creosote can run back down the chimney and if the fire is hot enough and or sparks go up the chimney you can get a fire going.

 

[Ambull01]

An ice age? Man that would kind of suck. Why you trying to kill my good mood? I just meant that weather system or whatever it was that pushed this cold weather down.

I've been looking for all the stuff you mentioned for a few months now. My wife has started to help me since this cold weather hit lol. Nothing like a cold, 20 degree slap in the face to make you realize you always have to be on the lookout for firewood. I'm soooo pissed right now because my saw is out of commission. Found where a power company came through and cut down a bunch of trees along a road. Rounds and logs all over the place. They are green and hernia heavy though. I need to buy a saw ASAP. Preferably two or more.

Umm, I can't believe you still burn after that. Brother in-law stopped last year or the year before. He had a chimney fire. Not exactly sure how it happened. I know he has a pre-EPA stove, he's never heard of a moisture meter, and probably didn't really season his firewood.

Is it like those CSL logs? I saw them at a local store near me. I was going to buy some but heard all the negative things about them on this site.

 

[Ambull01]

As a mech at work says unfortunately about ignorance and stupidity. "They walk among us".

You sir by definition are not ignorant. You realize issues and are thinking about them and seeking the answer. That is intelligence in my book.

Creosote can run back down the chimney and if the fire is hot enough and or sparks go up the chimney you can get a fire going.

Yes they my friend. This reminds me about a conversation I had with a fellow National Guardsman. Three of us got into his truck for a trip to Duncan Donuts. He has a new to him Chevy Silverado 2WD. He started to talk about the truck to my friend in the front seat. He says something about it having a 3.6 or 3.8 liter V8 and front wheel drive. I was like WHAT!? A truck with front wheel drive? Also, that's a tiny little V8. I asked to see his owner's manual in his glove compartment. Still had the stick in there and it clearly says a 5 something liter. Well he was still convinced it was front wheel drive. My friend backs him up and agrees most trucks are front wheel drive unless they have 4WD. In the name of all that is holy, how can people say stuff like that? I had to prove to those two numb nuts it was RWD. Anyway, I got totally off track with that story.

Running back down, now that's not good. I guess that could happen when it really builds up and becomes like tar.

 

[chuckwood]

>An ice age? Man that would kind of suck. Why you trying to kill my good mood? I just meant that weather system or >whatever it was that pushed this cold weather down.

According to all the reports I've been reading and watching, winter has started about a month early all over the nothern hemisphere, sea ice is already at record levels. Not a good sign.

>I'm soooo pissed right now because my saw is out of commission.

If you hang around in here long enough, you will develop a mental illness called "cad" or "chainsaw acquisition disorder".
You'll need at least four saws. Two small ones, two big ones. If one is on the workbench or in the shop, you'll need the other one so you can keep cutting. Then more saws will arrive, people will give them to you, you'll find them at flea markets and estate sales, on ebay, etc., and before long you'll have them arranged on shelves, all dripping bar oil all over the place and making a big mess. Your wife will be upset about it, but that's life......

>Found where a power company came through and cut down a bunch of trees along a road. Rounds and logs all over the >place. They are green and hernia heavy though. I need to buy a saw ASAP. Preferably two or more.

More than two. When you encounter the hernia rounds, you'll need the big saw to noodle 'em up into smaller pieces. That's the excuse you will use for buying the monster saw that has at least 80 cc.

>Umm, I can't believe you still burn after that. Brother in-law stopped last year or the year before. He had a chimney fire. >Not exactly sure how it happened. I know he has a pre-EPA stove, he's never heard of a moisture meter, and probably >didn't really season his firewood.

If you don't burn seasoned wood, the heat output of your stove will be poor, you'll stink up the neighborhood, and clog up your chimney. Your brother in law probably didn't clean his chimney on a routine basis.

>Is it like those CSL logs? I saw them at a local store near me. I was going to buy some but heard all the negative things >about them on this site.

I'm not familiar with CSL logs, the product I use comes in a large spray bottle. Home Depot here sells the stuff in the winter, it's made by Rutland, I believe.

 

[blades]

The log will help some with the flue. The spray is for cleaning glass and such- not the flue. Best choice is to practice 3 year rotation on split stacked wood. If ya do not want to do that then shift to the compressed blocks such as Ecco or Bio there others, but stay away from those that use wax as a binder such as pine mountain. Particularly true if purchasing your wood and relying on sellers that say it is seasoned ( only seasoning most of this sees is 2 stroke exhaust and bar oil). Fuel supply has to be less than 20 % moisture content for the newer stoves, even that is extremely marginal. 12/15 % is ideal, Lots are going to say I am off my rocker- nope sitin real solid and both legs match. Not being a smart ass - just stating the facts- aka Dragnet 101

 

[1project2many]

You don't have to understand digestion to enjoy a good steak. You don't have to understand how an engine works to practice good maintenance. Many people keep equipment nice without having detailed knowledge of how the equipment does its job.

I bought a stove from a friend that switched to pellets. The firebrick showed signs of excessive heat in only a few years of use. Why? The manual said the flue temp should be within a certain range to prevent creosote accumulation so that's he temp he maintained. He'd have windows open in the dead of winter and be throwing wood on the fire to maintain flue temp. Did he have any issues with creosote? None. Did he waste fuel? You bet. But no chimney fires, so it was ok in his book. But I think his approach wasn't the best. With wood burning there are few safety systems built in and there are quite a few variables involved in the process. Imo it's important to know some of the ways these variables interact.

I don't burn to maintain the flue temp. I burn for max heat in home on minimal wood usage. I tried to build the house chimney for maximum draw knowing that creosote forms as hot tars cool and condense on the cold chimney surface. I have to clean the spark arrester at the top a couple of times per season but the pipe is always fairly clean. A small amount of creosote forms in the pipe and it actually provides some insulation between the hot gases and cooler pipe. I can predict when we're going to have a problem with the spark arrester, too. When the outside temps are above 25 degrees, we're deep into the dense winter wood, and my wife is running the stove all day. She lets those high BTU logs smolder rather than over fire for complete combustion and a subsequent cooling cycle. Can't say as I blame her.

A big part of the key to clean pipe is the stove. As heat gasifies the log, hydrocarbons are released. These range from light HC's that burn easily to heavier tars which require more heat to react. With enough heat nearly all the gases will burn. EPA stoves attempt to provide the necessary heat and oxygen to react the HC's. If the HC's are burned before they get to the chimney they can't condense and form creosote. Heat is the key, even with a catalyst type stove. Older stoves often have no features to aid burning the heavy hydrocarbons so when stove temp drops, HC emissions go up dramatically and potential for creosote increases. Likewise, water in the combustion area of any stove inhibits combustion, robs the stove of heat energy, and causes unburned HC emissions to increase. Whether or not creosote actually forms is another issue.

Creosote is the result of unburned heavy HCs in the gas condensing in the chimney. So chimney temp plays a large part. So does the amount of time the gas spends in the chimney. Flue design is important. Gas doesn't actually flow through a chimney in a nice, neat column. Corners, bends, and junctions cause disturbances in flow and changes in speed. Speed will also vary with temp, which generally ranges from colder at the outside (moves slowly) to warmer at the center (moves faster). How and where the warm and cold layers form, combined with any changes due to pipe shape or curvature, will affect the physical makeup of creosote. Looser flakes can form if there's a good boundary layer keeping the warm center gas from contacting the cooler outer sections. Hard, dense creosote can be the result of warm gases directly contacting a very cool surface. If enough heat is lost before gases exit the chimney then drops of liquid creosote can form in the gas near the top and fall to the bottom and sides. But none of it is likely to burn unless there's some trigger.

Before a chimney fire begins something has to warm the creosote enough so it begins to turn into gas again. Running a hot fire with high draft after an extended time building smoldering fires or letting the creosote build so much that the inner diameter of the pipe is reduced putting hot core gases are constantly in direct contact with the buildup are two good ways do this. There must also be an ignition source. Ignition could be caused by a spark from the fire being carried up the chimney, or conceivably by the gases in the chimney reaching autoignition temps. And finally there must be enough oxygen available to support combustion. Excess draft or leaks in the pipes are sources of O2, especially when the fire's still small. Put fuel, oxygen, and ignition together and you've got a great potential for fire.

Long, long story short: Burn dry wood, use reburn or keep the catalyst warm, monitor chimney temp if possible. Get a feel for how well the insert burns. Have the chimney cleaned by a good sweep (or DIY if comfortable) and get plenty of feedback on what had built up in the chimney. Use this to judge your operation of the stove, the frequency of necessary cleanings, and the safety of your chimney. And above all, while you may relax over time, do not ever become complacent. There are too many stories of experienced burners being caught by surprise not to heed that warning.

 

[RVALUE]

The log will help some with the flue. The spray is for cleaning glass and such- not the flue. Best choice is to practice 3 year rotation on split stacked wood. If ya do not want to do that then shift to the compressed blocks such as Ecco or Bio there others, but stay away from those that use wax as a binder such as pine mountain. Particularly true if purchasing your wood and relying on sellers that say it is seasoned ( only seasoning most of this sees is 2 stroke exhaust and bar oil). Fuel supply has to be less than 20 % moisture content for the newer stoves, even that is extremely marginal. 12/15 % is ideal, Lots are going to say I am off my rocker- nope sitin real solid and both legs match. Not being a smart ass - just stating the facts- aka Dragnet 101

Hard of a concept to grasp as it is, there is a difference between "drying" (which happens rather quickly) and 'seasoning' (which is the two or 3 years you speak about.)

At least in Arkansas oak.

PS The best load of red oak in my cabinet shop that I ever got was from New Hampshire!

 

[zogger]

You didn't grab those used poulan and husky saws?

 

[Chris-PA]

I think one of the other issues for creosote build up is starting fires vs burning continuously. With a decent insulated SS liner in the middle of winter, the stove never really goes out and the flue never really gets cold, except at the top.

This year I did not run the brush up the flue, but only cleaned out the particles that fell down into the stove outlet. I just have not been getting much out of it and am more worried about damaging the liner with the brush, so I'm trying to limit the times I have to do that.

 

[blades]

Flexible liner? there is a nylon brush for that.

 

[Chris-PA]

Flexible liner? there is a nylon brush for that.

Yes, I'm looking for one locally.

 

[1project2many]

Hard of a concept to grasp as it is, there is a difference between "drying" (which happens rather quickly) and 'seasoning' (which is the two or 3 years you speak about.)

At least in Arkansas oak.

PS The best load of red oak in my cabinet shop that I ever got was from New Hampshire!

Interesting. I saw a paper somewhere about why NH Oak is preferred for furniture making and how landowners can work to ensure they grow trees with the right characteristics.

 

[Ambull01]

You don't have to understand digestion to enjoy a good steak. You don't have to understand how an engine works to practice good maintenance. Many people keep equipment nice without having detailed knowledge of how the equipment does its job.

I bought a stove from a friend that switched to pellets. The firebrick showed signs of excessive heat in only a few years of use. Why? The manual said the flue temp should be within a certain range to prevent creosote accumulation so that's he temp he maintained. He'd have windows open in the dead of winter and be throwing wood on the fire to maintain flue temp. Did he have any issues with creosote? None. Did he waste fuel? You bet. But no chimney fires, so it was ok in his book. But I think his approach wasn't the best. With wood burning there are few safety systems built in and there are quite a few variables involved in the process. Imo it's important to know some of the ways these variables interact.

I don't burn to maintain the flue temp. I burn for max heat in home on minimal wood usage. I tried to build the house chimney for maximum draw knowing that creosote forms as hot tars cool and condense on the cold chimney surface. I have to clean the spark arrester at the top a couple of times per season but the pipe is always fairly clean. A small amount of creosote forms in the pipe and it actually provides some insulation between the hot gases and cooler pipe. I can predict when we're going to have a problem with the spark arrester, too. When the outside temps are above 25 degrees, we're deep into the dense winter wood, and my wife is running the stove all day. She lets those high BTU logs smolder rather than over fire for complete combustion and a subsequent cooling cycle. Can't say as I blame her.

A big part of the key to clean pipe is the stove. As heat gasifies the log, hydrocarbons are released. These range from light HC's that burn easily to heavier tars which require more heat to react. With enough heat nearly all the gases will burn. EPA stoves attempt to provide the necessary heat and oxygen to react the HC's. If the HC's are burned before they get to the chimney they can't condense and form creosote. Heat is the key, even with a catalyst type stove. Older stoves often have no features to aid burning the heavy hydrocarbons so when stove temp drops, HC emissions go up dramatically and potential for creosote increases. Likewise, water in the combustion area of any stove inhibits combustion, robs the stove of heat energy, and causes unburned HC emissions to increase. Whether or not creosote actually forms is another issue.

Creosote is the result of unburned heavy HCs in the gas condensing in the chimney. So chimney temp plays a large part. So does the amount of time the gas spends in the chimney. Flue design is important. Gas doesn't actually flow through a chimney in a nice, neat column. Corners, bends, and junctions cause disturbances in flow and changes in speed. Speed will also vary with temp, which generally ranges from colder at the outside (moves slowly) to warmer at the center (moves faster). How and where the warm and cold layers form, combined with any changes due to pipe shape or curvature, will affect the physical makeup of creosote. Looser flakes can form if there's a good boundary layer keeping the warm center gas from contacting the cooler outer sections. Hard, dense creosote can be the result of warm gases directly contacting a very cool surface. If enough heat is lost before gases exit the chimney then drops of liquid creosote can form in the gas near the top and fall to the bottom and sides. But none of it is likely to burn unless there's some trigger.

Before a chimney fire begins something has to warm the creosote enough so it begins to turn into gas again. Running a hot fire with high draft after an extended time building smoldering fires or letting the creosote build so much that the inner diameter of the pipe is reduced putting hot core gases are constantly in direct contact with the buildup are two good ways do this. There must also be an ignition source. Ignition could be caused by a spark from the fire being carried up the chimney, or conceivably by the gases in the chimney reaching autoignition temps. And finally there must be enough oxygen available to support combustion. Excess draft or leaks in the pipes are sources of O2, especially when the fire's still small. Put fuel, oxygen, and ignition together and you've got a great potential for fire.

Long, long story short: Burn dry wood, use reburn or keep the catalyst warm, monitor chimney temp if possible. Get a feel for how well the insert burns. Have the chimney cleaned by a good sweep (or DIY if comfortable) and get plenty of feedback on what had built up in the chimney. Use this to judge your operation of the stove, the frequency of necessary cleanings, and the safety of your chimney. And above all, while you may relax over time, do not ever become complacent. There are too many stories of experienced burners being caught by surprise not to heed that warning.

Wow, thanks for taking the time to write that. I'm going to print it out and put it near the insert.

I didn't realize creosote burned as gas. I thought it burned in tar form.

 

[Ambull01]

You didn't grab those used poulan and husky saws?

Nope.

I emailed the seller twice but no response. I really, really wanted that Poulan. Must be an old ad that the seller forgot to remove.

 

[zogger]

Nope.

I emailed the seller twice but no response. I really, really wanted that Poulan. Must be an old ad that the seller forgot to remove.

That minty poulan 365 in the tradin post is pretty nice....

 

[Ambull01]

That minty poulan 365 in the tradin post is pretty nice....

I saw that, nice saw. $300. Therein lies the issue. Lets say I can pick up a HD 6421 for $200 or so. From what I've read, a great 60cc saw that's stoutly built. As the title of this thread plainly states, I'm an ignorant dude. One day I put in straight gas because I'm a knuckle head and never got around to actually labeling the straight fuel tank and the mixed tank. Top end commits suicide. I can get a BB kit for that 6421, make it a 84cc (I think) saw, and still be the same price as that Poulan.

 

[zogger]

I saw that, nice saw. $300. Therein lies the issue. Lets say I can pick up a HD 6421 for $200 or so. From what I've read, a great 60cc saw that's stoutly built. As the title of this thread plainly states, I'm an ignorant dude. One day I put in straight gas because I'm a knuckle head and never got around to actually labeling the straight fuel tank and the mixed tank. Top end commits suicide. I can get a BB kit for that 6421, make it a 84cc (I think) saw, and still be the same price as that Poulan.

IF you can still get the HD returns for 200 and in decent running shape, sure, get it. Word has been out for some years now, they get snatched up quick and I have read they have raised prices because of that.

Edit: wrap a buncha tape around the two stroke mix can handle. I do that plus, only mix at the pump, I don't pull from any of my other cans here. I mean, I would in an emergency, at the pump though I get exact quantity.

 

[Ambull01]

IF you can still get the HD returns for 200 and in decent running shape, sure, get it. Word has been out for some years now, they get snatched up quick and I have read they have raised prices because of that.

Edit: wrap a buncha tape around the two stroke mix can handle. I do that plus, only mix at the pump, I don't pull from any of my other cans here. I mean, I would in an emergency, at the pump though I get exact quantity.

Well that just ruined my month.

Tape is good idea. I should make it dummy proof by wrapping tape and write something with a Sharpie. After all, I have tried to jump start a car by putting the mixing up positive and negative. Woops

How does mixing at the pump ensure you get exact quantity? If there's measure marks on the can and the fuel is fresh, don't see an issue.