Why sweep a chimney that is being lined?

21 Oct 2014
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West Midlands
United Kingdom
Thinking of installing a wood burning stove and research I've done all states the existing chimney should be swept before installing the liner.

Seems reasonable, but why? The new clean liner is taking the hot smoke and gases away and they never come in contact with the old chimney.... is this a ploy to keep chimney sweeps in business?!
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Keep researching? Thanks for the insight....

As for pulling the liner through a load of soot and crap, I can understand the mess but don't see the issue once finished.

I'll probably get my chimney swept but was hoping for a "real" reason.
you may have flaimable material trapped between liner and flue
what you are aiming at is a safe sterile gap where heat will safely cross without problem
if the gap has anything that will burn in it like tar resin nesting material or other flamable material you can get a uncontroled burning off material requiring the local fire brigade
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Keep researching?

I'll probably get my chimney swept but was hoping for a "real" reason.
Vinn has probably been on the poteen don't be too hard on him, he does know the Heimlick manouvre. It's just the chip on his shoulder that makes him gyppy
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The Mighty Vinn does not need to elaborate - his word is law
Indeed, there are a few people here "to help" the newbies, yet kinda forget what the spirit of the site and who its target audience are

Shame really, because other times they're full of sage advice and go the extra mile for someone asking equally basic questions

Mood's a funny thing
Thanks to those who provided the info. Seems logical once explained. Now I am informed, if anyone asks me why a chimney should be swept I can provide them with the right answer.... keep researching.;)
You'll also get falling debris sitting on top of the register plate, that closes off the chimney......best get rid of what you can first - although burnt on resin is almost impossible to shift.
With your new installation, do ensure that sweeping is as easy as possible and that usually means a top outlet stove......sitting on top of a stack rodding downwards isn't always a joke!
John :)
With your new installation, do ensure that sweeping is as easy as possible and that usually means a top outlet stove......sitting on top of a stack rodding downwards isn't always a joke!
John :)
To clarify, sweeping of the chimney or liner? Chimney should not be receiving any more debris should it? How often should the liner be swept? Depends on usage?
Apologies.....sweep the chimney first as advised! In an old chimney, there will always be some debris in the form of parged cement compounds or whatever coming down.
As for the liner, it naturally depends on how often it is used and what you are burning.....personally I don't let my stoves smoulder overnight, but I don't have the flames roaring up the lum either.
I burn any timber that is 15% humidity or less if possible (very rare if the fuel is stored outside) and I also burn smokeless ovoids which don't flare but give out more heat than bitumen rich coal.....they also burn down to almost nothing.
I'd recommend a Stovax flue temperature gauge which helps you keep the fire to an ideal temperature, and I also like Eco Fans to distribute the heat too.
John :)
I'll probably get my chimney swept but was hoping for a "real" reason.
It is a real reason. Before you get up on the roof you need to know that the flue will go down without any obstructions. A core ball can also be sent down to make sure there is enough room for the liner.
It's unlikely a HETAS fitter would do a liner without a certificate from a sweep.
how I must have hurt you. Damaged you I suppose.
I am so sorry that you feel so bad - really.
- just lay off the w@nking and the poteen and keep practicing the Heimlick(y)
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Take a horse to water etc. you claimed to have done "research" but appear ignorant of "Similar Threads" at the bottom of every page where with a minimum of diligence you would find masses of recent threads explaining exactly what you complain about? Some research.

FWIW: You can indeed "provide the right answer" if you actually do the research instead of expecting to be spoon fed.
However, the main reason for sweeping has still not been mentioned - so what you would tell your hypothetical "anyone" would be incomplete.

AAMOI: Is it your intention to now go in for advising on flues and their sweeping eg. "providing right answers" - do you now consider yourself an expert on the subject?
Chill man. I asked a question and have had some helpful answers. If my research was not up to your standards it doesn't prevent me from posting and others answering. A forum by its nature has a range of people from pros to novices, me being much nearer the latter.

As for considering myself an expert and advising others on flues and sweeping.... don't be a plum.
Do you consider simply reading to the bottom of the same page a "standard ... of research"?
You can post anything you want but why expect to be spoon fed answers.
Where do you consider that you've been prevented from posting?
And now you are intent on explaining how this/a forum works? Not bad for someone who wont read to the bottom of a page.
Then in what capacity would you be advising someone who asked you about flues etc? Would it be on the always be prepared principle - like knowing the Heimlech Maneuvre or the names of everybody who lives in China?

FWIW: further research is still needed by you - read my posts and see why.
Vinn, I have no intention on getting on the wrong side of you or justifying myself when I'm simply on the forum for knowledge on some home projects.

Written posts don't convey people's intentions well, but I get a negative feel from your replies to me. Don't really feel I've warranted it, so let's just leave it here. Others have not done so. No probs, no ill feelings. All cool.

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