Creosote entering second skin of flue, and falling into house

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Neo1.6

New Member
Jun 7, 2017
6
NSW, Australia
Hi All,

I had a Pacific Energy Neo 1.6 wood burner installed last winter, which has a triple skin flue from ceiling to exterior. This was installed by a local builder (whom certified the installation, required in Aus, NSW). I’ve had the bloke around to correct the flue once already as it was extremely crooked and looked terrible from the exterior of the house, but ever since it was corrected I am getting creosote falling through the vent holes in the ceiling plate which I have to clean up each day. I initially thought this was a result of a small amount of creosote entering the second layer due to what ever the bloke did to straighten up the flue, however it has been 7 months since the fix (and 4 months since fireplace was last used) and this creosote is still entering the house each day (pictured)

The installer seems to be ignoring my last request to come have a look at the issue, I’ve given up and would rather instead hire someone else to fix it properly or do it myself.

Before I start, is there a common cause for something like this or best place to start?
I.e is there likely a gap in the first flue layer which may be allowing smoke to enter the second, or more likely some sort of gap at the very top near the flue cap.
 

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The flue system should be continuous from stove to chimney cap. There should be no chance of creosote occurring outside the inner lining nor at that location. Something is definitely amuck. This should be inspected and corrected by a good certified sweep and not the builder.
 
Yup. Something isn't connected properly. It should be gone right through before use. I would be looking first at the ceiling support box to make sure the stovepipe adapter is in place and connected properly to the first piece of chimney.
 
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A possible cause--
Some USA branded triple wall Chimney pipe upon removing the top-cap for cleaning, exposes the openings ("air insulating") at the top. Then, upon sweeping, it is easily possible for creosote to flip over & down the air spaces when the brush comes to the top. One needs to close off these spaces when sweeping. Such a piece of misplaced creosote that drops clear to the bottom, i.e., the ceiling transition, can possibly start afire when chimney gets warm enough. This is scarily dangerous, and I have seen it happen.

The whole chimney system needs to be taken apart & all creosote pieces in the cavities removed. I hate triple wall pipe -- the stuff should be banned. I have, also, seen triple wall that was not connected properly, have these conditions. Extremely dangerous if a chimney fire ever occurs! Luckily, in both cases, folks were home & got the fires in the wrong places put out, chimneys subsequently torn apart, cleaned & re-assembled correctly. Better, just to replace with good quality "modern" double wall chimney
 
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It could just be missing the simple stainless snap adapter that goes between the end of the black pipe to the class a pipe.
 
So far no success in finding a trade to repair this flue. Had a chimney sweep over recently to at least clean it out for me and give a recommendation (wasn’t interested in doing the reinstall). Apparently the active pipe does not line up with the cowl and pipe is possibly a few centimetres short allowing some soot/creosote to fall back into the other layers of flue. The inner and outer sections of flue are hard up against each other and can’t be realigned with the cowl/cap. As he brushed the flue, quite a lot of soot seemed to fall back inside the house.

B7CFD62F-60C0-4186-AC4C-76FB77B510B9.jpeg
81CCA08E-749C-419E-A061-1CCB88857624.jpeg

Now the ceiling plate seems to be chockablock, the slightest vibration causes a shower.

FE2F49F3-CC6C-4DB6-96CA-D569E17C5770.jpeg
 
A few centimeters short is a lot. It sounds like air is getting into the stove connector pipe and cooling down the flue gases. Depending on the stove pipe, either replace a section of the stove pipe with an adjustable stove pipe that makes up that gap. Or perhaps adding an appliance adapter in the flue collar will make up the gap?
 
Update: So its all been pulled apart and redone, there were a number of problems with the install.

- There was a gap in the active pipe between a join which caused smoke to enter the second skin. Creosote was building up in this layer and falling back down through the ceiling plate. Even though the flue had been cleaned, everything sitting in other layers made a real mess in the roof space/house once the sections were pulled apart.

- as the roof ridge was slightly in the road, rather than use a propper bend/angle the original installer just bent the sections of pipes at joins to try to manouver around it. This causes the layers of flue to be hard up against each other rather than seperated by an air gap, and then of course the top cowl didn't joint up properly with the active pipe, thus causing more crud to cool at the top and fall back down the chimney. A bend is now installed along with a few new sections of pipe.

- The cieling plate was misaligned with the outer skins which mean the vent holes allowed air to enter straight into the roof space

- A ceiling joist had been cut and left unsupport, which has been remedied


Fingers crossed its all good now.
 
Wow, that is quite a list or serious errors. I'm glad you got it straightened out and properly repaired. The builder is lucky he didn't cause a tragedy. Will the builder be covering the cost of repairs?
 
Yep it’s been a bit of a bugger trying to get it all sorted, this weekends job is to get up there and check it all over one last time before the cooler weather hits and it’s fired up.

Lesson learnt though, my inexperience with wood heaters meant I did not see the risk for what it was early on.

I doubt the original builder will care much once informed, but it’s a small town, it will cost him in other jobs from word of mouth.
 
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Yep it’s been a bit of a bugger trying to get it all sorted, this weekends job is to get up there and check it all over one last time before the cooler weather hits and it’s fired up.

Lesson learnt though, my inexperience with wood heaters meant I did not see the risk for what it was early on.

I doubt the original builder will care much once informed, but it’s a small town, it will cost him in other jobs from word of mouth.
Good job following this through. Sounds like a tough situation. I'd find the organization that provides the certification for the builder and file a formal complaint. You could be saving lives, the guy needs to get his act together before someone burns up due to his shoddy work. Particularly since he is ignoring you now.
 
Yep it’s been a bit of a bugger trying to get it all sorted, this weekends job is to get up there and check it all over one last time before the cooler weather hits and it’s fired up.

Lesson learnt though, my inexperience with wood heaters meant I did not see the risk for what it was early on.

I doubt the original builder will care much once informed, but it’s a small town, it will cost him in other jobs from word of mouth.
I'd forward him a copy of the bill with a note that his incompetence and haste could have cost lives.
 
Yep it’s been a bit of a bugger trying to get it all sorted, this weekends job is to get up there and check it all over one last time before the cooler weather hits and it’s fired up.

Lesson learnt though, my inexperience with wood heaters meant I did not see the risk for what it was early on.

I doubt the original builder will care much once informed, but it’s a small town, it will cost him in other jobs from word of mouth.
And TELL everyone you meet...
 
This kind of story is scary. If not for the obvious mess, a less observant owner may not have noticed any problems and just trusted the "professional". I wonder how often this kind of thing happens especially when the problems are hidden.
 
I wonder how often this kind of thing happens especially when the problems are hidden.
Far too frequently and not just for stove installs.
 
I would like to caution the OP to be careful about what he says and how he says it. Keep good documentation so you can prove what you do say to avoid any possible libel issues if the contractor loses business and pushes it. This one seems pretty obvious, but documentation is everything.