Charnwood Downdraft fix with external air vent.

[slim reaper]

Difficult to tell the brand  externally from distance as there are quite a few of them.

Selkirk have their label stuck on the inner skin just below the spiggot end  on each length but there may be one on the cheek of the base support.

Although Selkirk have one of the best distance to combustables ,unboxed and boxed,for internal use the exterior seam joint has a rougher raised finish.

Edited January 7, 2021 by slim reaper

[patrickgalloway3]

My woodburner has an external twin wall flu and also has a problem with smoking when first lit. I tend to open a window before I light it and close the window a minute later. Once warm it has no issues.

[neiln]

On 05/01/2021 at 23:50, openspaceman said:

I'm not an installer but, cold flues will be more trouble, so warm with a few sheets is newspaper or a heat gun.  It looks like your house is new ish, and probably not that drafty.  The window opening thing indicates this.  Double glazing and seals on openers and on doors? Any trickle vents? Any loo cisterns with overflow pipe through the wall or probably in to the bowl? Solid floors? It could be tight enough sealed that even a 5kw stove is touch and go for struggling to breath from the room.  An air brick, or an outside air kit for the stove (If it takes one) is an easy fix.  Raising the flue is also worthwhile.... Longer should draw better irrespective of where the ridge is.  The H cowl may help, but if it isn't a wind/turbulence thing causing the trouble it might do nothing.  I'd add the air brick and extend the flue.

 

 

[openspaceman]

25 minutes ago, neiln said:

 

For some reason Neil's new content got attributed to me.

 

The only thing is that the problem may well be because of wind conditions around the house, my thoughts on an internal circulation was just another possibility

[neiln]

Sorry my fault. I was going to quote something then thought it didn't help and on the smart phone I've deleted the content of the quote not the whole quote!  Oops.  Not trying to put words in your mouth!

[openspaceman]

11 minutes ago, neiln said:

Sorry my fault. I was going to quote something then thought it didn't help and on the smart phone I've deleted the content of the quote not the whole quote!  Oops.  Not trying to put words in your mouth!

Not a problem and nothing to disagree in that post, I have never thought about toilet cistern overflows but modern ones are internal and into the bowl.

[neiln]

Yeah it's just one of the changes to houses that make modern houses more sealed. Solid floors or fitted carpets, rubber seals on doors and window openers, overflows, I'm sure there's more I can't think of right now, a modern house is a lot more air tight then older houses were. So the 'air vent of certain size for every kW over 5' in building regs ought to be treated as just a guide perhaps, I've a feeling the wording does say something about more may be needed if the house is well sealed.

[Gtflash]

Found the details.  It is MI tl pro.  I think it will take 1.5m unsupported pipe upward, I think it’s about 500mm to bottom of cowl from bracket so does that mean I can stick 1000mm on top?   Does that height include the cowl?   Supplier do a few lengths 300,500,1000,1200.   

[openspaceman]

1 hour ago, Gtflash said:

Found the details.  It is MI tl pro.  I think it will take 1.5m unsupported pipe upward, I think it’s about 500mm to bottom of cowl from bracket so does that mean I can stick 1000mm on top?   Does that height include the cowl?   Supplier do a few lengths 300,500,1000,1200.   

Sorry I don't know but personally would risk 1 metre.

 

How does the cost compare with fitting the sealed air kit?

 

I just looked and £49 so for the sake of a core drill, flexible exhaust pipe and that...

Edited January 7, 2021 by openspaceman

[slim reaper]

You could use one of these to stiffen it up and go 2.5m above your last support, support being the band on the facia.

Sflue Stove Flue for Wood Burning Stoves - 150mm - Structural Locking Band - Painted Black.

WWW.FLUESYSTEMS.COM

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Sflue is a prefabricated, factory made twin wall insulated stainless steel chimney system. Used mainly with wood...

 

Edited January 7, 2021 by slim reaper