Wood burner install question - to line or not to line

30 Mar 2015
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West Glamorgan
United Kingdom
Hi, hoping someone can help me understand, I have had two Hetas fitters come and give me quotes for fitting a wood burner (both approved fitters on the Hetas website)
My chimney is lined with clay pots at the moment (gas fire removed recently and I live in a bungalow if that helps)
I'm buying the fire and hearth-approx £750 for both so the prices below exclude that

First fitter has quoted me £1200, to include the extra fire fittings and flue liner, brickwork, plastering, hearth fitting etc (total cost about £1950). He says the liner is essential

Second fitter has quoted me £700 (total cost about £1450) to include the same work but says I don't need to line the chimney as the clay pots are in great condition and are sufficient

Can someone explain why the advice would differ like this, from a safety perspective I'm confused. Plus, isn't the other reason for the liner so that the fire works properly by reducing the diameter of the flue to that of the fire ie from the 9" current clay pots to 5"?
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I would price you to drop a liner... Reason is you may suffer from issues of water condensing on the walls of the ceramic flue, running down and dripping all over your nice new stove and hearth....It will be black and nasty. A liner reduces this condensation and will ensure that any condensation will run back into the stove and be boiled away...

It is not an issue of safety but you don't want dirty black water dripping all over the shop... The first guy may be a little more experienced than the second
I thought a Liner was mandatory?

How is anyone supposed to know how tight a flue is without a full inspection, which of course you can't do without a camera.
I thought a Liner was mandatory?

How is anyone supposed to know how tight a flue is without a full inspection, which of course you can't do without a camera.

You do a type 1 (?) flue test. Seal both ends of the flue an smoke bomb.
You don't fit a liner to gas flue "!just in case", so why for a stove?

You are not likely to suffer condensation in a bungalow. You are more likely to suffer from poor flow, which IS a good reason for lining.

It isn't mandatory to fit a liner, it depends on MI's and state/condition/height/CSA of flue
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I think the poor flow issue is making me lean to the first guy, he also pointed out what extra work he'd need to do as the flue isn't in the centre of the fireplace, the second guy didn't seem to notice until I mentioned it and then he re calculated what he needed to do
For the sake of another £500 I think I'd feel more comfortable knowing the job is right and the fire will work as it's designed to
I'd go with the second guy. Except the flue connection would have to be done to my design specifications.
That involves making a compression ring that fits the vitreous enamel flue diameter. Which effects a very tight seal between the vitreous enamel flue and the chimney liners. And still allows longtitulal expansion and contraction.
A metal liner only lasts a few years and then you have to replace them.
A bit like an exhaust on a car.
Ignore Norcon, he's a weed smoking Leprechaun. His method would fail if you do suffer from condensation..
Ive installed a few of these tho none in the UK.

For the best results AND no horrible black stuff seeping thro the brickwork into the room in future years I would always fit a stainless liner of the diameter recommended by the manufacturer.

After the liner is in place fill the void between the old clay chimney and the new stainless liner with a suitable fireproof/insulation granular material (sorry cannot remember the English product name).

I used to remover the top of the chimney and lower the stainless sections down to the fire, joining them with fireproof glue/sealant (it came in a normal silicone sealant type tube), and when it was in place pour the granules around the centralised (very important) stainless chimney pipe.

Best of all have the stainless pipe exposed in the room, way better than any radiator........as long as you don't touch it )-:

Oh, I should add that these were all fitted on my own houses and the last one I fitted in 1999 and is still fault free.

Best of luck.
I run two wood burners down here in France one a Godin cooker the other a Harmony III both have un-insulated stainless flues running up through a large chimney. I also know someone who burns a harmony III who has terrible problems with black filth running down the stainless flue. The reason this happens is because A) the wood being burned is not seasoned as well as it could be and B) the stove is not burning properly. I never have any problems with my stoves because I always make sure they are burning properly that means with enough air to burn without excess smoke which creates less tar and generates more heat which in turn keeps the flue warm and prevents condensation. In short I don't think you need a liner but you must burn the stove properly otherwise you will have problems even with a liner fitted!!

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