New house - Creosote dripping - Help

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mcmurray

New Member
May 25, 2014
15
Northern Ireland
Firstly, great forum. I've read some threads on creosote so I know a bit already but I'm trying to find a definitive answer to my own problem. Please bear with me as it is quite long winded.

I recently moved into a new house (3 weeks ago). The house is a new build (unsure of chimney construction). We paid a little extra when it was being built to have a multi-fuel stove fitted.

On first use of the stove, I burned some small sticks that I had in the shed for over a year. The wood felt dry but after around 15 minutes we discovered creosote dripping onto the top of the stove. The fire burned well but I'm guessing now that the wood was too wet. I let the fire go out to stop the dripping.

I tried a second time a few days later and had the same problem.

We contacted the guy who installed it and he gave us a Chimney Cleaning Log (CCL) to burn to get rid of the creosote (last night). The CCL burned fine with little to no dripping. I added some logs to the fire later that night. They had a moisture reading of 22% on a moisture meter. Again the dripping started. It wasn't a small amount of creosote either, it was at least 150-200ml.

The installer thinks that we burned loads of wet wood but it was only a small amount of sticks over the first 2 fires. He insists that it will take at least a week of burning to get rid of the dripping, I'm not so sure.

I don't think it could be this bad from burning such a small amount at the start?

I've attached some photos of the pipe and where the creosote has stained the plaster from dripping. Also added a youtube link to a video showing the problem one night after it had started dripping.

I thought that this sort of stuff shouldn't be leaking on the outside of the pipework?

In total, the stove has been lit about 5 times.

Any advice from someone more knowledgable than me would be greatly appreciated as I'm starting to get worried? What should I do?


Thanks in advance,
Ryan



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No way any of that should be happening. The builder, the stove installer, everyone involved in any way with that installation should be brought face to face with it. Less than dry wood could be a source of creosote, but there's gotta be more than just that going on. Properly installed, the system should return any liquid formed within the flue all the way back down to the firebox of the appliance. It would help to know the make & model of the burner, and whatever details you may be able to provide about the flue, including a pic or two from outside the house showing the height and how the thing gets to daylight. I wouldn't use it again until all these problems are solved. Welcome to the forums. Rick
 
Something is WAY wrong. Do not use until you get that solved. There is NO way that is from your wood on your first fire.
 
That moisture isn't coming from the wood. It is cooking out of something and running down the outside of the pipe. Is that black stuff sticky? If not it isn't cresosote.
 
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Maybe it's melting something inside the wall?
 
In any case, there's something seriously wrong somewhere in the installation, and I'd consider it to be unsafe to operate until everything is fixed. Rick
 
For sure. Be dog wide.
 
Thanks everybody for the quick response.


I was lucky enough to have the problem when the builder was at the house across the road during one of the first times I used it. I called him in and showed him the dripping. He said he hadn't seen that happen before. He then phoned the stove installer who gave him the same message he later gave me. That the wood must have been wet.

Thing is, if I go back to the installer he is going to tell me to continue to light it until the moisture goes away.

I was going to buy a couple more of the creosote type logs but I'm not so sure this is going to fix the problem.

I can't see any visible branding on the stove but here is a photo of it and also a photo of the chimney on the house.



Ryan


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That moisture isn't coming from the wood. It is cooking out of something and running down the outside of the pipe. Is that black stuff sticky? If not it isn't cresosote.


It was sticky when hitting the stove and boiling. I've since started to collect it in a fireproof dish to stop the smell of burning. It has a potent smell and looks like, what I can best describe as used motor oil, only not as thick.
 
You need to take a scramble up in the attic with your camera, sorta looks like the transition unit through the ceiling isn't correct and that the pass through the roof/roofing was not done correctly . Where the flue passes through the roof there should be a gap that is not filled in( maybe some one filled that with roofing tar), externally that is covered by a cone that matches the roof angle on the bottom and fits tight to the outside of the flue at its top . Just above that should be a rain shield. Both of these joints should be sealed with High temp silicone material. On a new build that should be an insulated ( double wall at minimum) from the transition unit through the roofing up to the flue cap, with a minimum of 3ft above the peak of anything inside a 10 ft. radius.
Inside the Attic the transition unit should have a shield to keep insulation away from the flue pass through area. There should be a air gap around this section of flue pipe as well and not tight to the ceiling drywall. The flue pipes themselves should have the crimped section facing down into the one below it.
By the way in my less than adequate opinion that ceiling transistion is incorrect and it looks like there is a 45 deg off set there as well , is this a cathedral ceiling? as it looks awful thick.
 
As the guys say,don't burn till it's inspected . That transition through the drywall looks to be all wrong with my old man eyes. Looks like some sorta offset or something..could be just the pic but I don't even see the trim ring.
Noway is that from what little wood you have burned..it does look like heated tar.
Like said go into the attic and see if the goo is on the pipe near roof.
 
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Well the pics you added says more..I guess forget going into the attic for a peak since it is a outside chimney. Still somebody goofed up somewhere.
No way would I burn that stove till I had a pro look it all over. You already have damage that you should not fix or pay to have fixed.
That damage is not from burning off moisture!
 
Well the pics you added says more..I guess forget going into the attic for a peak since it is a outside chimney. Still somebody goofed up somewhere.
No way would I burn that stove till I had a pro look it all over. You already have damage that you should not fix or pay to have fixed.


Thanks for the advice though. I know little to nothing about this sort of thing so all advice is appreciated.

I'll update this thread as and when I get more info on the problem and possible solution.

We haven't paid for the stove yet so we're not out of pocket just yet. The builder has been great, so can't see any issue with him in getting it sorted.
 
Judging from the photo of your stove sitting in the alcove it's hard for me to believe you have meant the necessary clearances. I've never seen specs on a stove that would allow such close clearances (assuming your walls have wooden studs and drywall over them). Have you taken any temperature readings with an IR thermometer to see how hot the walls and ceiling inside the alcove are getting when you are burning? I'll bet if you get a good fire going in your stove that in less than an hour your walls are reading way higher than what would be considered safe. As for the dripping material, as others have said it's hard to believe it to be creosote from the description you've given. Please don't burn another fire until you get things checked out by an independent chimney sweep or other professional. Good luck on getting everything taken care of.
 
Thanks for the advice though. I know little to nothing about this sort of thing so all advice is appreciated.

I'll update this thread as and when I get more info on the problem and possible solution.

We haven't paid for the stove yet so we're not out of pocket just yet. The builder has been great, so can't see any issue with him in getting it sorted.

It seems you have certainly have kept your cool and that is very respectable. Me? I would have been flipping out at the first sight of that gunk!
Nick Mystic added some very good observations..heed him.
As they say fire is nothing to play with.
 
Judging from the photo of your stove sitting in the alcove it's hard for me to believe you have meant the necessary clearances. I've never seen specs on a stove that would allow such close clearances (assuming your walls have wooden studs and drywall over them). Have you taken any temperature readings with an IR thermometer to see how hot the walls and ceiling inside the alcove are getting when you are burning? I'll bet if you get a good fire going in your stove that in less than an hour your walls are reading way higher than what would be considered safe. As for the dripping material, as others have said it's hard to believe it to be creosote from the description you've given. Please don't burn another fire until you get things checked out by an independent chimney sweep or other professional. Good luck on getting everything taken care of.


I've never measured the heat. The installer has been in business of fireplaces/stoves for as long as I can remember so I just assumed he would know what he was doing. The walls in the alcove are solid brick/block with a rough render of plaster over them as the chimney is 'outside'.


It seems you have certainly have kept your cool and that is very respectable. Me? I would have been flipping out at the first sight of that gunk!


I'm ready to lose my cool but I find with situations like this, it's better to be reserved. People are more willing to help if you're not screaming at them.
 
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I'm very curious how this plays out... I know less than zero about building codes and practices outside the US.
I can only agree that that DEFINITELY isn't creosote. It's an improperly-installed chimney bleeding.

Please keep us up to date on the resolution your builder comes up with.
 
I am wondering whether your problem is due to the chimney being new and still moist. What I can imagine is that the heat from the fire drives out the moisture from the mortar. Do you have a steel liner all the way up to the top? Maybe that has a leak somewhere, the smoke mixes with the moisture and then starts dripping down. Getting a pro sweep in who can lower a camera down the chimney to check the liner may help. The moisture problem may also more or less solve itself over the summer when the mortar had time to dry out completely. Still, you don't want a leaky chimney.
 
I'm very curious how this plays out... I know less than zero about building codes and practices outside the US.
I can only agree that that DEFINITELY isn't creosote. It's an improperly-installed chimney bleeding.

Please keep us up to date on the resolution your builder comes up with.


Thanks for your input.

All these posts have been very helpful.


I am wondering whether your problem is due to the chimney being new and still moist. What I can imagine is that the heat from the fire drives out the moisture from the mortar. Do you have a steel liner all the way up to the top? Maybe that has a leak somewhere, the smoke mixes with the moisture and then starts dripping down. Getting a pro sweep in who can lower a camera down the chimney to check the liner may help. The moisture problem may also more or less solve itself over the summer when the mortar had time to dry out completely. Still, you don't want a leaky chimney.

I'm not sure of the chimney liner. I'll find out when I next speak to the builder.

The builder's initial thought was that it was water that had collected inside the chimney before the rain cap was fitted.
 
By the way, very nice house.
 
Not sure what the hell that pipe is connecting to? Radiation shield? The materials around where the piping goes through the ceiling of the alcove better be non combustible, or else it ain't the required 2" from the pipe.
I wonder if the installer installed the piping upside down and this is running out the seams and down the outside of the piping?
Bet there is more than one thing wrong with that install.

That is stainless and not galvanized pipe right?
The white crap sure looks like the crap that comes off galvanized when it heats up and gets wet.
Unless it is double wall, which some does have s.s. inner and galv outer shells.

Builder is an aasshat if he expects you to continue burning that set up.
New house, all should be under warranty, and builder needs to address and correct the issues, period!
 
Although we don't have all the same parts and requirements as Ireland I expect there are many similarities. For sure the entire hearth alcove has to be entirely made of non-combustible materials, right? Is the builder in the process of making another house with a similar chimney setup? If so, maybe you can photograph it as it is being built? If not, have the mason explain in detail (and with drawings) how the flue system is constructed.

What is wrong with the mason's and builder's explanation is that a flue system should never leak creosote. Never. If it is leaking, there is a flaw. That is dangerous because creosote is combustible. It should not be pooling up around a hot flue pipe. Dripping on a hot stove is quite dangerous! The builder's explanation of rain getting down the chimney does not explain how the rain water became a black tarry goo. Any combustion by-product should remain in the flue liner. Also, your wood fire does not look lazy. It's vigor seems to show the wood is reasonably well seasoned.

The flaw can be in the materials or in the way they were installed. A proper flue system should not drip creosote even if you were burning green wood. As to what is wrong, we can only guess because there appears to be no way to visibly inspect the work. It could be a worker didn't mechanically fasten a pipe joint together and it came apart. Or it could be that the pipe was installed inverted (if there are crimp joints at each pipe section.) To resolve this issue I think it may take making an inspection opening on the face of the hearth above the stove. Or, they need to pull the entire liner from the chimney and inspect for flaws. You may need a dis-interested party's professional opinion to back this up. If the builder and mason continue to stonewall, consider hiring a professional chimney sweep or perhaps the local fire marshall to inspect and write up a report.

PS: Was this work inspected by a local inspector before it was sealed up?
 
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If that is a standard European house construction, the walls consist of cinderblocks, mortar and a layer of plaster on top. For the alcove and chimney, it is bricks, natural stone and mortar. The only combustible material in such walls could be foam insulation or wiring. However, I don't think the builder was that stupid. There are no studs or drywall to be concerned of.

Nevertheless, the whole setup should be inspected by an independent pro. The chimney is certainly not built properly.
 
That pipe looks like it is just connected to the tile flue pipe with a collar at the transition from the stove pipe to the masonry chimney terra cotta lining.
 
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If so, maybe an inspection camera will show the flaw?
 
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