10 Year old wood stove pipe still emitting smell when too hot

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FrankP

New Member
Dec 9, 2016
12
Upstate NY
Hello all.

Had the smoke alarm go off in the middle of the night that had the family up. Ran into the living room thinking I would find smoke. I didn't. It was that harsh chemical smell that my pipe lets off when randomly the stove gets too hot.

Every thing I have read says this only happens when breaking the stove in. My stove is 10 years old and has been doing this every now and then since I purchased it. Smoke alarm only went off once before like 5 years ago. Last night the smell was probably the worst I ever smelled it. The pipe is a double insulated black pipe.

The stove was dampened down too which makes me scratch my head. Does anyone know why I might be experiencing this? I had a suspicion of wood being too dry? But I believe last night I loaded with a pretty heavy wood.

This is driving me crazy on why this only happens sometimes. Both fire getting too hot as well as stove pipe emitting a horrible smell.
 
Do you have a flue thermometer? Lots of variables could play into this. What is the MC of your wood? If your wood is super dry it will run hotter than usual. How cold was it last night? The colder it gets the stronger your draft will be. When is the last time you checked all of your gaskets? If you have an air leak somewhere your stove will run hot which means your pipe will run hot. What I have read here is everytime your stove and flue hit a new high temp it will smell like hot paint.
 
Do you have a flue thermometer? Lots of variables could play into this. What is the MC of your wood? If your wood is super dry it will run hotter than usual. How cold was it last night? The colder it gets the stronger your draft will be. When is the last time you checked all of your gaskets? If you have an air leak somewhere your stove will run hot which means your pipe will run hot. What I have read here is everytime your stove and flue hit a new high temp it will smell like hot paint.

This is all great input. I do not have a flue thermometer, I'm assuming your asking moisture content of wood? I have no clue. I do have a batch of wood leftover from last year that was over seasoned even then. That wood I have been mixing in and it is VERY dry. It was very cold last night 10º. And you really got my attention with the gaskets question. I have noticed my side load door doesn't have that tight fit anymore. Gasket is fully there but indented. Also when cleaning it this year I noticed all the top gaskets could probably use replacing. Makes total sense how I can have this dampened down so much and it randomly will create a blazing hot fire. And I believe last time I had this pipe smell was a very cold evening. Thanks for your input!

I attached a photo of the stove.
 

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This is all great input. I do not have a flue thermometer, I'm assuming your asking moisture content of wood? I have no clue. I do have a batch of wood leftover from last year that was over seasoned even then. That wood I have been mixing in and it is VERY dry. It was very cold last night 10º. And you really got my attention with the gaskets question. I have noticed my side load door doesn't have that tight fit anymore. Gasket is fully there but indented. Also when cleaning it this year I noticed all the top gaskets could probably use replacing. Makes total sense how I can have this dampened down so much and it randomly will create a blazing hot fire. And I believe last time I had this pipe smell was a very cold evening. Thanks for your input!

I attached a photo of the stove.


Dude not for nothing man but stop burning period until you find out what is wrong or at least stay up all night to see what is going on. When you first experienced this years ago you should have taken drastic measures to ensure the safety of everyone and your house.

Order new gaskets, get a stove pipe thermometer or at least a ir gun. You can get them online for cheap or from your local harbor freight store or a local hearth shop. Some parts you gotta get from online and hearth shop. If your pipe is getting that hot then you def have something wrong, I mean it's slow getting hotter and hotter to the point it's burning the paint off.

What time was is when the alarm when out and what time was it Shawn you last adjusted your air?
 
Last night the smell was probably the worst I ever smelled it.

When was the last time you professionally cleaned your stove, pipes and chimney? If not recently, I am suspecting creosote.

The stove was dampened down too which makes me scratch my head. Does anyone know why I might be experiencing this? I had a suspicion of wood being too dry? But I believe last night I loaded with a pretty heavy wood.

Well, over damping at the wrong time with heavy wood may lead to a sub optimal, incomplete burn. Those can really smell bad. Wood needs heat and good air flow to burn properly, at least to start before strong pyrolsyis can predominate, and if chocked of air until then, it can really stink. And sub optimal burning will then continue to stink for a long time, until (if) you get to a proper charcoal smoldering phase. Many reasons and a variety of smelly hydrocarbons are to blame, but one significant reason may be, again, generating creosote. It may also generate CO, which you can not smell. The leaking gasket may be why you are smelling something (of the hydrocarbons that you can smell). And if, so, that actually may have been a good thing, as it may have saved your life. I agree with Niko, for safety sakes, you should find the actual and root cause before burning again.

Hope this helps.
 
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And when I figure out the exact temps of the pipe then what? What do you do from there? The smell is right at the pipe you can put your nose to it and smell it. It smells exactly like what people in other forums have described when breaking their stove in. My mystery is why would mine still let that smell off from time to time. Like I previously said only one time ever did it set an alarm off. That was like 5 years ago. I have read in forums that it was common for peoples smoke detector to go off when pipe got to hot during break in period. There was zero smoke in house and carbon monoxide detector wasn't going off. Without doubt when the smell does happen its when the pipe is very hot.

This stove was professionally installed, but I don't believe the store is in business anymore. Im gonna see if I can contact a place tomorrow to see if I can get a thorough inspection of everything. Im sure I could replace gaskets but would like to have it fully looked over. its our main source of heat.
 
Any chance it is built up creo burning off or baking in the pipe, that you are smelling?
 
If your smoke alarm went off, you got smoke in the house. Knowing your flue temps will help determine if it's smoke that came off the paint on the outside of your pipe or if it's smoke that escaping from your system somehow and getting into the house.

It's burning wood in your home. Temperature is everything.

Can you get to your cap and check what it looks like?

Having a sweep in to clean and check everything over seems like a good decision.
 
Sounds like time for new pipe. May be the case of a bad batch of paint that won't cure. I have read about bad paint batches that caused pipe to stink over long periods of time.
 
If you have little to no creo than I would say you are burning hot and clean. Maybe just a little too hot. Beautiful stove by the way. Is that a PE or enviro? If you have never done any gasket work I would start there. Replace all of the gaskets and adjust any door latches. Also you need to get a moisture meter for your wood. Any big box store will have them. Probably not tractor supply because tractor supply never seems to have what you need. Also get a stove top thermometer and a flue probe thermometer. It's not needed but I would get an IR thermometer as well. The magnetic thermometers are often not exact. I have three thermometers on my stove and an IR.
 
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Sounds like time for new pipe. May be the case of a bad batch of paint that won't cure. I have read about bad paint batches that caused pipe to stink over long periods of time.
That would be my take too. We have circa 2006 Simpson DVL stove pipe. They used a lacquer based paint that does not bond well to the pipe. If the stove pipe is running too hot then the paint smells. This can become more apparent in colder weather due to stronger draft. If the stove gasket is getting a little tired and leaky the stove pipe could be getting very hot inside when the stove is damped down. I recommend a probe thermometer to know what the flue temps are. When our flue temps are >900º the pipe starts to smell. A recent gasket failure caused this to happen and it was that smell that was my first alert. I will be replacing this section of pipe next summer.
 
Any possible chance you damped down on a fire containing some wetter splits? I have done that a few times early this year and got a strong stink. Finally figured the pile I had gotten into was a bit wet. Had the smell a few times. Nothing again since getting into my well seasoned wood. Just a thought. Hard to believe you still have paint cure stink?
 
Our pipe is 10 yrs old and it still will stink when hot. If one can smell smoke from a damp split in the stove once the door is closed there is a leakage problem. BK stoves can exhibit this problem. Theory is the creosote from smoldering soaks the door gasket. But the smell is different.
 
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Haaa. Guessing my stink was coming from the cat temp probe hole. Hard to say. My bad on trying to utilize some incorrectly seasoned wood. Only took a few loads to figure it out;em
 
I've had some experiences with my old stove where I was running the stove hot all evening, had a great bead of coals, reloaded the stove and turned it down a little to burn for the night and 5-10 mins later got puff back. From what I concluded, such a hot bed of coals caused the fresh load to off gas a lot and because the damper was turned down some it wasn't getting enough fresh oxygen to burn the combustible gasses. Once the wood got hot enough and could flame up the entire firebox would combust and "fluff". Thats called deflegration. Basically a subsonic explosion (ignition) of combustible gasses. It wasn't forceful enough to blow anything apart but it would cause flue gas to get blown out of the air intake and any air leak in the chimney pipe. Because my stove had a thermostatic air damper I could hear that damper bang open when it would happen. The best method I came up with to address it was to leave the stove dire open so it's drawing enough oxygen and drafting harder to remove the gasses. This same phenomenon can happen with a small bed of coals too where the firebox gets saturated with combustible smoke, the. The coals get hot enough to ignite a flame. You really have to observe this in action to know that it's happening. When it happened to me it was within 20 mins of reloading but more frequently around 10 mins or so. Good luck.

Edit,
Once it ignited it would burn like an inferno. However, I believe it's possible what set your alarm off could have been the smoke blowing back.
 
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Haaa. Guessing my stink was coming from the cat temp probe hole. Hard to say. My bad on trying to utilize some incorrectly seasoned wood. Only took a few loads to figure it out;em
Most folks with BKs report it from the door or door glass gasket. Poorly seasoned wood is no fun in any stove, cat or non-cat.
 
I've had some experiences with my old stove where I was running the stove hot all evening, had a great bead of coals, reloaded the stove and turned it down a little to burn for the night and 5-10 mins later got puff back. From what I concluded, such a hot bed of coals caused the fresh load to off gas a lot and because the damper was turned down some it wasn't getting enough fresh oxygen to burn the combustible gasses. Once the wood got hot enough and could flame up the entire firebox would combust and "fluff". Thats called deflegration. Basically a subsonic explosion (ignition) of combustible gasses. It wasn't forceful enough to blow anything apart but it would cause flue gas to get blown out of the air intake and any air leak in the chimney pipe. Because my stove had a thermostatic air damper I could hear that damper bang open when it would happen. The best method I came up with to address it was to leave the stove dire open so it's drawing enough oxygen and drafting harder to remove the gasses. This same phenomenon can happen with a small bed of coals too where the firebox gets saturated with combustible smoke, the. The coals get hot enough to ignite a flame. You really have to observe this in action to know that it's happening. When it happened to me it was within 20 mins of reloading but more frequently around 10 mins or so. Good luck.

Edit,
Once it ignited it would burn like an inferno. However, I believe it's possible what set your alarm off could have been the smoke blowing back.
AKA puffback. Not usually an issue with good dry wood in a secondary tube stove that has good draft, but more common in downdraft stoves and some cat stoves. Poorly seasoned wood and/or weak draft can exacerbate the issue.
 
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You should regasket anyway. The first comment about reaching a new high temperature was likely the cause. An air leak would. A use that hot burn. But how does the fire look? Are you getting a good secondary burn at a slow pace? If so, that's good. You should have both pipe and stove top thermometers and use them to keep in burn temperature range. If your secondary burn is too fast, and your gaskets are good you could have too great a draft, for this an old fashioned damper in the stovepipe will help.
I agree with comments that you should figure it out and correct. You may have to sit a m d watch it at length to observe these various conditions and pin it down. All part of the experience.
 
Thanks everyone for your input. I think I'm gonna have a professional come out and check it out. I have a child in the house now and want to make sure everything is proper on this. Im sure a new gasket on door is definitely needed but I want a professional to fully look this thing over. The one suggestion I don't fully comprehend is a thermometer on my pipe? Now lets say the thermometer tells me the pipe is too hot then what do you do? It's not like I can turn a knob to make the fire cooler. What is the advantage? And like I said previously this episode happened like 5 years ago (initiated smoke alarm from harsh smell). Gaskets were all in very good shape then.

So what it comes down to is why sometimes does this wood stove get so hot it emits a harsh smell when doing the same procedure I always do. I dampened it down last night before bed the same way I do every night for 10 winters in a row.
 
Sounds like time for new pipe. May be the case of a bad batch of paint that won't cure. I have read about bad paint batches that caused pipe to stink over long periods of time.

This sounds logical. Then the second thing I would have to figure out is why at random times is the wood stove driving the temps up to make the pain smell when doing the same procedure I always do. Unless I'm missing a small detail I overlook that causes the specific fires to burn hotter than the norm.
 
That would be my take too. We have circa 2006 Simpson DVL stove pipe. They used a lacquer based paint that does not bond well to the pipe. If the stove pipe is running too hot then the paint smells. This can become more apparent in colder weather due to stronger draft. If the stove gasket is getting a little tired and leaky the stove pipe could be getting very hot inside when the stove is damped down. I recommend a probe thermometer to know what the flue temps are. When our flue temps are >900º the pipe starts to smell. A recent gasket failure caused this to happen and it was that smell that was my first alert. I will be replacing this section of pipe next summer.

Interesting. This stove was installed around October of 2007 along with the piping. The piping could very well be from 2006.
 
Thanks everyone for your input. I think I'm gonna have a professional come out and check it out. I have a child in the house now and want to make sure everything is proper on this. Im sure a new gasket on door is definitely needed but I want a professional to fully look this thing over. The one suggestion I don't fully comprehend is a thermometer on my pipe? Now lets say the thermometer tells me the pipe is too hot then what do you do? It's not like I can turn a knob to make the fire cooler. What is the advantage? And like I said previously this episode happened like 5 years ago (initiated smoke alarm from harsh smell). Gaskets were all in very good shape then.

So what it comes down to is why sometimes does this wood stove get so hot it emits a harsh smell when doing the same procedure I always do. I dampened it down last night before bed the same way I do every night for 10 winters in a row.

Well something happened differently than every other night. Smoke alarm in the middle of the night is unnerving as all hell I imagine. A thermometer will allow you to monitor and asses the performance of your stove, and even if you have zero interest in that it will tell you just how hot you're getting in an event like you had. Otherwise who knows how hot things were?
 
Thanks everyone for your input. I think I'm gonna have a professional come out and check it out. I have a child in the house now and want to make sure everything is proper on this. Im sure a new gasket on door is definitely needed but I want a professional to fully look this thing over. The one suggestion I don't fully comprehend is a thermometer on my pipe? Now lets say the thermometer tells me the pipe is too hot then what do you do? It's not like I can turn a knob to make the fire cooler. What is the advantage? And like I said previously this episode happened like 5 years ago (initiated smoke alarm from harsh smell). Gaskets were all in very good shape then.

So what it comes down to is why sometimes does this wood stove get so hot it emits a harsh smell when doing the same procedure I always do. I dampened it down last night before bed the same way I do every night for 10 winters in a row.
If you find the temp of the flue is getting too hot there could be several reasons. A common one is that the air is being turned down too slowly or too late. With a flue thermometer that becomes your guide, not the stove top temp. Also, wood can vary and sometimes be dryer than previous batches. A flue thermometer can also alert you to when something like a door gasket is failing. We had exactly that scenario happen with our stove last week. Up to that point the stove behaved like a pussycat.
 
Pipe gets hot enough to stink sometimes. Very little out of the pipe when cleaning. Chimney fires?
 
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