Suggestions needed to feed a rigid tube liner above the roof with a flat concrete top.

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yonny33

Member
Feb 9, 2021
120
Uruguay
I think as the liner will come up to the top of the wide sleeve just under the reductor I'm going to clamp it here. Rivot these supports on the side of the sleeve (if it will take the weight) and clamp this to the liner with a big jubilee clip. Easy access and adjustable from here.

IMG_20210315_200330.jpg IMG_20210315_200342.jpg IMG_20210315_202035.jpg IMG_20210315_202047.jpg
 

begreen

Mooderator
Staff member
Nov 18, 2005
90,546
South Puget Sound, WA
Yes just the top, from the plate through the concrete top and extending about 50cm in total height not including the cowl.
OK, then insulating the liner with a wrap below that point makes more sense and is recommended. This definitely is one of the more unusual installations we have seen.
 
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yonny33

Member
Feb 9, 2021
120
Uruguay
OK, then insulating the liner with a wrap below that point makes more sense and is recommended. This definitely is one of the more unusual installations we have seen.
Great thanks for the advice again.
Just weighed one section, just over 1.6 kgs.
So almost 10kgs in total. If I can I'll make a lower support also. Just something simple
 

gthomas785

Minister of Fire
Feb 8, 2020
530
Central MA
I think as the liner will come up to the top of the wide sleeve just under the reductor I'm going to clamp it here. Rivot these supports on the side of the sleeve (if it will take the weight) and clamp this to the liner with a big jubilee clip. Easy access and adjustable from here.

View attachment 276470 View attachment 276471 View attachment 276472 View attachment 276473
You've basically fabricated your own double wall insulated chimney pipe. Excellent work.
 

yonny33

Member
Feb 9, 2021
120
Uruguay
Another doubt - If I use aluminum tape to wrap the ceramic fiber or even the rock wool what kind of temperature will the outer surface of the insulation get to?

Concerned about the sticky aluminum tape getting too hot. Will it be ok?
One seller says it is good to 120c , another 250c but they look the same- not much. I've seen a 3m good to 600c but not in this country.
 
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gthomas785

Minister of Fire
Feb 8, 2020
530
Central MA
Another doubt - If I use aluminum tape to wrap the ceramic fiber or even the rock wool what kind of temperature will the outer surface of the insulation get to?

Concerned about the sticky aluminum tape getting too hot. Will it be ok?
One seller says it is good to 120c , another 250c but they look the same- not much. I've seen a 3m good to 600c but not in this country.
That really depends on so many things. Type of stove and how hot you run it, how much insulation is there, and how much airflow around the outside of the insulation.

Typical chimney temperatures (inside) can range from 120C all the way up to 500 C or hotter. With a layer of metal, then insulation, I'd expect the outside surface temp to be much lower than that. A standard Class A insulated pipe usually only gets warm to the touch under normal operation, and is rated for 5cm clearance to combustibles.
 
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yonny33

Member
Feb 9, 2021
120
Uruguay
Just fabricated this effective clamp from some spare parts and cut offs.
 

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yonny33

Member
Feb 9, 2021
120
Uruguay
This is a better option of rock wool:

already shaped for tubes and 25mm option.
Waiting for a quote
 

begreen

Mooderator
Staff member
Nov 18, 2005
90,546
South Puget Sound, WA
This is a better option of rock wool:

already shaped for tubes and 25mm option.
Waiting for a quote
That looks more practical.
 

yonny33

Member
Feb 9, 2021
120
Uruguay
That looks more practical.

Out of luck, I'm afraid. They only have 63mm thickness with 140mm internal diameter. That won't fit.
Double the cost of the previous ceramic fiber 12mm also.

Update: Found another supplier with 25mm ceramic fiber - 60 bucks for a 7.2m roll (0.61cm wide).
The other ceramic fiber seller was being silly with the shipping costs and not very helpful at all.

oh boy wish we had Home depot or Wickes here. Miss these big stores around the country. All these suppliers here are miles away and all centralized near the port in one small district part of the old town. Such a pain to get to if they don't offer postage.
 
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gthomas785

Minister of Fire
Feb 8, 2020
530
Central MA
Out of luck, I'm afraid. They only have 63mm thickness with 140mm internal diameter. That won't fit.
Double the cost of the previous ceramic fiber 12mm also.

Update: Found another supplier with 25mm ceramic fiber - 60 bucks for a 7.2m roll (0.61cm wide).
The other ceramic fiber seller was being silly with the shipping costs and not very helpful at all.

oh boy wish we had Home depot or Wickes here. Miss these big stores around the country. All these suppliers here are miles away and all centralized near the port in one small district part of the old town. Such a pain to get to if they don't offer postage.
:(
 

yonny33

Member
Feb 9, 2021
120
Uruguay
Amazon Amazon Amazon prime oh I miss you!! My next day delivery (2 hour even) and returns policy I had in the UK. :( When life was so much easier.

You just cannot win!

One supplier wants 250 pesos for shipping
The other 200 mtrs away wants 900 pesos for the same size roll!!!

Making money from shipping by the looks of it. :mad:
 
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yonny33

Member
Feb 9, 2021
120
Uruguay
Think I'll give this a miss from the seller (long explanation :eek: ,been a long enough search last thing I need now is a long phone call.)

I'll just go for the 12mm 5 metre length of ceramic fiber and finish the whole issue.

Appears the foil-wrapped in the rock wool is only good up to 82c!!! Good job I saw that.

Please call me
094xxxxxx
I have several options and a long explanation to talk about
This was from the super expensive option also.
 

gthomas785

Minister of Fire
Feb 8, 2020
530
Central MA
Wow, I've never seen rockwool rated to such a low temperature. Maybe they used some polymer based binder or it has a plastic vapor barrier incorporated? Anyway, good catch.
 
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yonny33

Member
Feb 9, 2021
120
Uruguay
We had some fairly strong winds last night (30mph+) and instead of all the wind blowing down the flue filling the living room with a strong odor of old smoke from the stained brickwork it was nice and odor-free!!! The new type of wind cowl seems to work quite well.
Just need some semi-tropical torrential rain to test its effectiveness now. Possibly Saturday.

I would still like to fit a damper with a lever though. The stove guy is looking for one for me. (I asked a so-called experienced flue/liner fabricator and he just had no idea, clueless, and totally unhelpful and willing to make a damper. Appears they just do what they know and no more). It's a struggle I tell you!

IMG_20210313_183928.jpg
 
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gthomas785

Minister of Fire
Feb 8, 2020
530
Central MA
We had some fairly strong winds last night (30mph+) and instead of all the wind blowing down the flue filling the living room with a strong odor of old smoke from the stained brickwork it was nice and odor-free!!! The new type of wind cowl seems to work quite well.
Just need some semi-tropical torrential rain to test its effectiveness now. Possibly Saturday.

I would still like to fit a damper with a lever though. The stove guy is looking for one for me. (I asked a so-called experienced flue/liner fabricator and he just had no idea, clueless, and totally unhelpful and willing to make a damper. Appears they just do what they know and no more). It's a struggle I tell you!

View attachment 276641
Are you referring to a flue damper like this? Or something else..
1616080902648.png
 

gthomas785

Minister of Fire
Feb 8, 2020
530
Central MA
yep or something like this already integrated into a 2mm section:

Best of luck finding it. Depending on your stove however, you may not need one. They are typically used to restrict the flow in cases when the draft is excessive, usually due to a tall chimney. In your case, 5 meters is not really that tall.
 
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yonny33

Member
Feb 9, 2021
120
Uruguay
Best of luck finding it. Depending on your stove however, you may not need one. They are typically used to restrict the flow in cases when the draft is excessive, usually due to a tall chimney. In your case, 5 meters is not really that tall.

Are they at all useful to stop backdraft when not in use?
 

gthomas785

Minister of Fire
Feb 8, 2020
530
Central MA
Maybe a little, but not really. All the ones I've seen have holes in them so "closed" is about 20% open. Either way it certainly wouldn't hurt to have it.
 
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PaulOinMA

Minister of Fire
Oct 20, 2018
1,085
MA
Looks great.

Some dampers were in a collection of cast iron cookware I bought in 2011. Too bad you're not nearby. If you have trouble finding something, I could look into mailing you one, if I have the size you need.

010 - Copy.JPG
 
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PaulOinMA

Minister of Fire
Oct 20, 2018
1,085
MA
That damper from Kratki made me think of the damper in the exhaust chimney of my barbeque smoker.

I think you mentioned Home Depot. There are dampers like it at a HD in the area here.
 
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