Total creosote clog and CHIMNEY FIRE: THREE WEEKS after brand-new install?!

[Toba Guy]

Ok, so here is the story.

Just got my first ever woodstove installed, Quadra-fire Isle Royale, with top-loading door.

It was installed professionally (though I'm really beginning to question if he deserves that title).

Stove is located in the basement, no outdoor air kit, drawing from inside the house. Flue damper also installed.

Pipe goes up through the main-floor, into our bedroom where it takes two elbows (approx 45 degrees each), to hit the roof at the proper angle to pass between the joists etc.

For 3 weeks burned more or less continuously. About half scrap 2x4s, and half seasoned pine.

Kept the damper at minimum, and played with the flue damper to a point where the flames were blue and dancing.

Did not allow it to smoulder to restart from the embers, but used paper and bark/kindling each time to restart. Then added scraps, then the pine.

After 3 weeks of pure wood-burning pleasure, without any issues or concerns, there was a strong smell of burning-plastic in the main-floor bedroom. Then shortly after a strong smell of woodsmoke. Then the 2" insulated pipe was too hot to leave my hand on. THEN there was a dramatic decrease in draw in the stove. Carbon monoxide detector went off, reading of 89 PPM in the bedroom.

Contacted the installer, and we tried to light it again (a few days later). No-go. No draw at all. Took the flue damper off and put a straight pipe in instead. No-go, still no draw. Went up on the roof, and the cap itself was totally, completely plugged with creosote. Taking the cap off allowed us to get a fire going, but the draw was still terrible. No smoke or carbon monoxide exited into the bedroom during this fire.

Installer says it is an issue of negative pressure in the basement (our furnace also draws straight from inside the house). Says this has slowed down the ascent of the smoke, to the point that it is cooling and condensing on the pipe.

During the 3 weeks of burning, draw was never a problem. Never had smoke pouring out of the stove, trouble lighting etc.

Installer also says a major factor is the humidity in our house (+/- 45%, down to 35% after running the stove).

And the "punky" wood we have. I'm familiar with this term, and to my mind our wood is absolutely not punky. My brother has been burning from the same batch since September and has had no complaints. It is totally dry, well-seasoned for at least a year. The installer does not contest any moisture issue with the wood, but he says it has "lost all of its energy" and that some of it was cut from dead trees: "never ,ever burn deadfall".) I think he may be trying to shift the blame onto us to cover his butt.

I don't doubt that the negative pressure is part of the problem here, but my real question is: to your mind, does this explain how we somehow managed to completely clog our chimney with creosote in a matter of 3 weeks?!

Seems to me something in this system was grossly miscalculated. When originally purchasing the stove, sales rep said we would essentially never have to clean the chimney, because the stove burnt so clean. Install guy had said we should have it done once per year. I work from home and was at that fire every 1.5 hours having a great time with my new stove, tweaking and tuning the flue damper, keeping the flames blue and rolling: was this the issue?

Even the flue damper was covered in creosote. How is this possible in THREE WEEKS?!

Thoughts? Insight?

Will provide further details if helpful.


Thanks.

 

[Blackjack Dan]

Wow be safe & be careful and get a second opinion on the install.

Don't know much about that stove it's one I'm looking at purchasing for my own use. What I have read though A flue damper is a big question mark?. You should get the temp up in the stove and then close the internal damper some call it a bypass after the stove reaches the correct temperature. If this unit has one control for both air regulation and bypass then it's imperative to get the stove to the correct operating temperature while making sure the flue damper is wide open and probably should not be used.

 

[TheRambler]

Do you have a flue probe/ temp thermometer? Stove top therm? Have you actually checked the wood with a moisture meter?(need to check a fresh split face)

I am leaning towards you are keeping the flue temps way too cool as the root of the problem. Your flue damper is probably not needed, and since it too was covered in creosote it points more towards too cool flue temps.Though there could certainly be other issues as well.

Before you even attempt to use the stove again i would thoroughly clean the flue.

 

[gzecc]

My vote is bad fuel. Fuel is the single most important part of the equation, unless you have some funky designed chimney.

 

[firefighterjake]

Sad to say . . . but usually creosote is due to the fuel . . . or not running the stove and flue hot enough.

Do you happen to have a stove or flue thermometer with readings?

 

[webby3650]

That pine isn't as dry as you think! It's also highly unlikely you ever needed that flue damper, it's not needed on new stoves unless the flue is very tall.
Negative pressure didn't cause this issue, if that was the issue you would have been experiencing sluggish starts and smoking prior to this event.

I can't believe the cap wasn't the first place the installer looked! Has the chimney been cleaned and inspected since this happened? If the cap is that bad, the rest of the flue is likely not much better.

 

[maple1]

My guess is the pine isn't dry enough, and your draft isn't as good as you think - likely the damper hurt too.

Was the draft actually measured? No temp data either, anywhere - both should be monitored especially in a new install. If everything is drawing inside air, that's another thing that can pull your chimney draft down. You'll be grasping at straws until you get back to starting with a completely clean chimney, and measured/monitored draft. Dry wood + proper draft should not build creosote.

 

[TheRambler]

Its definitely one or the other or a combination. Fuel, flue temps, or both. If your pine has been cut split and stacked for a year as you say then it should be good to go. Pine is one of those woods that seasons relatively quickly. Should be verified with a moisture meter to rule it out though.

 

[Jags]

You are running way too cool and fuel could be an issue as well. I see no mention of thermometers or temps. You state that the damper was used as well as the primary was kept at a minimum. I don't like to jump to conclusion this fast, but currently this is pointing to operator error. Please don't take offense to that. You are not the first (or last).

Obviously step one is to sweep and inspect your flue before you do anything else.

Second - get two thermometers. One for the stove top and a second probe type for the stack.

Can I take a guess that you were seeing smoke from the pipe almost 100% of the time except for the coaling stage?
Glass all smoked up?

 

[claydogg84]

Why was the flue damper even installed? You should have only the air control to adjust on the stove.

 

[Plow Boy]

You said "seasoned" pine. I just wondering with this being a new install, how long have you prepared for the stove by seasoning wood. Or did u get the pine from someone who said it was "seasoned". My guess is the pine is green, that coupled with an unnecessary damper in the stove pipe caused a serious problem (to say the least). Pine has a bad rep. around here because if you burn it to green your going to have trouble eventually. Burning hardwoods green is bad, but pine is way worse; and can lead to a big pile of ashes where your house use to be.

 

[Laurent Cyr]

All comments here were valid. Flue temp and stove temp is too low. Your damper is probably not needed. Your pipes will need a good cleaning before you start over. The first year I bought my stove, the creosote layer was heavier than it is now. I found the raging fire in the stove intimidating, so I kept the temps down way too low. With the years, I've learned.

 

[begreen]

Most likely the wood and possibly the way the stove is being run. We need to know some temperatures to discuss how the stove is run. Is there a thermometer on the stove top or stove flue? The negative pressure claim sounds a bit fishy, but we need more data on how the stove is being run first. Most likely it's being run too cool.

Just as a check, can you describe the flue system in a bit more detail? Is there single-wall or double-wall connector pipe to the basement ceiling? How tall? From the basement ceiling through the roof there should be chimney pipe (stainless steel, shiny, probably 8" diam.). Is this the way it is? The 45s should be 30 degree angle elbows and made of the same chimney pipe. Is this correct?

PS: Welcome to Hearth.com. You have a good stove. With good fuel and proper running it should provide a lot of warm satisfaction.

 

[saskwoodburner]

This being my first season running a epa style wood stove, my thoughts are to blame the wood and technique as well (with no offense intended). Once you have a way to measure your temps, you'll know how far you can go, and once you figure out how to burn correctly, you'll get there.

As for punky wood, it can be dry, and still be punky. It's what my son calls movie prop wood, that round that should weigh 10 lbs being like 3 lbs as an example.

 

[maple1]

Also on the wood, windfalls can be bad, or they can be good. I have burned a crapload of windfall spruce the past 3 years, as I needed dry wood in a hurry. If you get it before it starts to turn punky, and split & stack it in a dry open space, it can 'finish' in a couple months. If it starts to go punky, it can actually soak up water rather than dry out. So punky can be either dry as a bone with next to no heat energy & likely make no creasote, or it can be wet & make a bunch of creosote (still with little heat engergy). Stuff I cut was up off the ground resting on the branches, if the windfall was laying right on the ground that's not usually good either - you have to catch it pretty quick before it goes backwards.

Also think I have to throw a flag on the part about the humidity - that should have no impact on making creosote. Although if you have a poor draft to start with, it might compound it a little bit, I suppose, and make it more sluggish.

 

[DougA]

And the "punky" wood we have. I'm familiar with this term, and to my mind our wood is absolutely not punky. My brother has been burning from the same batch since September and has had no complaints. It is totally dry, wellseasoned for at least a year. The installer does not contest any moisture issue with the wood, but he says it has "lost all of its energy" and that some of it was cut from dead trees: "never ,ever burn deadfall".) I think he may be trying to shift the blame onto us to cover his butt.

If the pine is deadfall and covered for a year, it should be dry and not cause you any problems. To be fair, your brother may be burning the same wood on a different stove and have no problems because his stove is a different design. One year of proper seasoning with pine and it should be fine. Punky wood "has lost it's energy" yes, I agree that it has lost probably 50%. But if it is dry and free, many of us use it anyway and it will not cause creosote problems. More likely punky wood (when dry) burns too fast and can cause short, hot fires. That can be good if you are wanting to heat the house up quickly but you need to make sure that you are indeed not choking back the stove unless it is overheating.

Like others suggest, buy a brush & clean the chimney, get 2 thermometers (one for top and one flue probe) and a moisture meter to check your wood. All of those will be under a hundred bucks, even in Canada. THEN, you have the information needed for us to help you better.

I honestly can't imagine anything an installer could do (other than put in a damper, which is not necessary) that could cause the problem. Like others, I suspect the wood is not as dry as you thought and you are running the stove too cool. Glad you posted and we're here to help you enjoy your investment.

 

[branchburner]

If your pine has been cut split and stacked for a year as you say then it should be good to go. Pine is one of those woods that seasons relatively quickly.

Also a wood that reabsorbs moisture pretty readily, so as DougA mentioned: cut, split and stacked for a year and THEN COVERED (or moved into a shed/barn) well before the coming burn season, to prevent reabsorbing moisture.

Toba Guy, when you kept the damper at minimum, and played with the flue damper to a point where the flames were blue and dancing, you were unknowingly creating creosote by keeping the fire too cool to allow a good secondary combustion (= burning smoke). This is how we ran our airtight VC back in the late 70s, resulting in quick, heavy buildup and a severe chimney fire.

EPA stoves are made to run fairly hard and hot, with lots of draft and lots of air supply, to get the high temps needed to re-burn the smoke/particulate. (Cat stoves being a bit different, as the cat allows smoke to burn at cooler temps.) Once your flue is cleaned, and you get a thermometer to measure flue temps, you should reverse your technique to get hotter burns rather than cooler, slower ones.

Unfortunately, burning 50% dry 2x4s is not conducive to good burning in an EPA stove: you will either overfire the stove or produce too much off-gassing too quickly to be get proper secondary combustion. The % of small scrap to be burned will probably need to be much lower for optimal burning.

 

[Lumber-Jack]

I've heard all that pitch in pine will plug up your chimney and causes chimney fires out East. You may have to move out West here if you want to continue burning pine, no such rumor exist out here.

 

[TheRambler]

Also a wood that reabsorbs moisture pretty readily, so as DougA mentioned: cut, split and stacked for a year and THEN COVERED (or moved into a shed/barn) well before the coming burn season, to prevent reabsorbing moisture.

Toba Guy, when you kept the damper at minimum, and played with the flue damper to a point where the flames were blue and dancing, you were unknowingly creating creosote by keeping the fire too cool to allow a good secondary combustion (= burning smoke). This is how we ran our airtight VC back in the late 70s, resulting in quick, heavy buildup and a severe chimney fire.

EPA stoves are made to run fairly hard and hot, with lots of draft and lots of air supply, to get the high temps needed to re-burn the smoke/particulate. (Cat stoves being a bit different, as the cat allows smoke to burn at cooler temps.) Once your flue is cleaned, and you get a thermometer to measure flue temps, you should reverse your technique to get hotter burns rather than cooler, slower ones.

Unfortunately, burning 50% dry 2x4s is not conducive to good burning in an EPA stove: you will either overfire the stove or produce too much off-gassing too quickly to be get proper secondary combustion. The % of small scrap to be burned will probably need to be much lower for optimal burning.

Last part of my previous post was to verify the wood with a moisture meter to rule it out. If your wood is covered or not it doesnt make a ton of difference in the grand scheme of things. If its cut, split, and stacked off the ground in a spot that gets good wind and sun then it will season just fine. Wood does or rather can reabsorb moisture, but its negligible if its cut, split, and stacked in a location that in conducive to seasoning firewood. I challenge you to try an experiment. Take a piece of seasoned pine for example, split it and check the moisture content. Then take 1 of those pieces and put it in a 5 gallon bucket of water. Leave it there for a few days to a week and then come back and split that piece again and check it again. Split the one that wasnt in the bucket too and compare. I already know what you will see. Sure the outside few layers of wood will be wetter/can reabsorb moisture, but the main portion of any given piece of wood wont reabsorb any meaningful amount of water unless its left there for a really long period of time. It certainly can't hurt to cover your wood, and i certainly do. But it doesnt make that big of a difference. And any wood that does reabsorb moisture, wont absorb nearly enough to take it from "seasoned" to marginal again after its already seasoned to a point that is considered ready to burn. At least not in the majority of locations that people are storing firewood anyway, maybe it would be a different story if you live in a rain forest or the tropics.

Burning scrap wood isnt an issue either. Yes if you load your stove completely full with it you can run into an overfire situation potentially, but mixing it with cord wood is a perfectly fine practice, and is done frequently by many people. Its no different than burning pallets, or burning biobricks etc. Split a 2x4 and check the moisture, most of them arnt super dry, but are certainly in the ideal range. I checked a few out of curiosity a couple weeks back and they ranged from 15-20%

 

[DougA]

I challenge you to try an experiment.

I agree 100% EXCEPT if the wood is punky. Punky wood absorbs moisture very quickly and I find it dries slowly because it's wet inside. I have not done this experiment on punky wood and I will leave that to you. If you find the same results, I will bow in your honor and beg forgiveness.

I suspect the wood is not as dry as the OP thinks and that factor, plus the learning curve we all experience on a new stove is the what's gone wrong. Even then, gee, that's a really short time to get clogged up!

This thread is a good one though.

 

[bholler]

i find it amusing that the op hasn't responded yet and you guys keep theorizing i am curious to see what they have to say

 

[TheRambler]

I agree 100% EXCEPT if the wood is punky. Punky wood absorbs moisture very quickly and I find it dries slowly because it's wet inside. I have not done this experiment on punky wood and I will leave that to you. If you find the same results, I will bow in your honor and beg forgiveness.

I suspect the wood is not as dry as the OP thinks and that factor, plus the learning curve we all experience on a new stove is the what's gone wrong. Even then, gee, that's a really short time to get clogged up!

This thread is a good one though.

Agreed, punky wood is a different animal. Though i would think the average joe would know if the wood is punky. And i am just giving the OP the benefit of the doubt when we says that he knows what punky is, and is wood is not that.

 

[MattFoley772]

In my Isle Royale I burned mostly pallets and lumber which are pine for whole winter and had almost zero creosote in prefab chimney after winter. So I will bet you are burning wet wood and/or not burning hot enough after loading. Does the wood pop and hiss? Does it give off a lot of smoke? Does it ignite quickly or take a while? Are flames bright yellow or blue, or a darker orange? Do you always load it up and restrict the air or do you burn smaller hot fires regularly?

 

[DougA]

Agreed, punky wood is a different animal. Though i would think the average joe would know if the wood is punky. And i am just giving the OP the benefit of the doubt when we says that he knows what punky is, and is wood is not that.

Point taken. That's not a bow though, only a nod.

 

[firefighterjake]

i find it amusing that the op hasn't responded yet and you guys keep theorizing i am curious to see what they have to say

I think we might have scared him.