Concealed Gas flue in listed building

[JohnW2]

I didn't. It is covered in the technical bulletin as a "concealed room-sealed fan-draught boiler chimney/flue systems"

I'm getting rather confused. I thought the reason we were talking about these two W-B "Greenstar" boliers was that, fairly uniquely, they could be used with the W-B "Flexible Flue System (see here) up an existing chimney - I imagined without an 'inspectability' requirement, which would presumably be essentially impossible with most chimneys?

Most people selling these boilers seem to include this sentence in their description:

These boilers are compatible with a flexible flue system which means that the boiler’s flue can be routed through an existing brick chimney.

Kind Regards, John

 

[denso13]

I thought the reason we were talking about these two W-B "Greenstar" boliers was that, fairly uniquely, they could be used with the W-B "Flexible Flue System (see here) up an existing chimney

Yes, but it still has to follow the rules of "flues in voids", which it is.

I think only a site inspection can confirm what is required/allowed, as it seems a fairly unique situation, i.e., listed building with a roof terrace above the top floor flat. Where does the chimney terminate?

One other point, the terminal for the flexible flue is a fairly large, ugly plastic/metal affair. If an inconspicuous normal flue outlet isn't allowed on the listed building, I doubt that this sticking out of the chimney will be either. Needs confirming on site.

 

[JohnW2]

Yes, but it still has to follow the rules of "flues in voids", which it is.

As I said, I'm confused, since it would be so rare for it to be practical to have 'inspection hatches' throughout the length of a flue within an existing chimney (particularly given that boilers are commonly on the ground floor of a ≥2 storey building) that I wouldn't think they would bother to make (and try to sell) them if they could only be used with such access?

I think only a site inspection can confirm what is required/allowed, as it seems a fairly unique situation, i.e., listed building with a roof terrace above the top floor flat. Where does the chimney terminate?

Again, I find it hard to believe that they would bother to make them if they could only be used (if at all) in such "fairly uniique situations"

One other point, the terminal for the flexible flue is a fairly large, ugly plastic/metal affair. If an inconspicuous normal flue outlet isn't allowed on the listed building, I doubt that this sticking out of the chimney will be either. Needs confirming on site.

Yes, that occurred to me, too - but that question is moot unless/until it is established that it would be allowed from the gas point-of-view.

Kind Regards, John

 

[denso13]

until it is established that it would be allowed from the gas point-of-view.

And that can't be done here, there are too many questions. I can only find flue instructions on the manufacturer's website that date from 2009 and refer to CORGI, not Gas Safe. Strange all round.

 

[SUNRAY]

Request sent to to mod to move this to plumbing and heating.

 

[JohnW2]

Request sent to to mod to move this to plumbing and heating.

It really needs 'splitting', rather than 'moving', since the OP and nearly all of the first page were about electrical cable sizing, and plumbers/heating engineers are probably not the best people to be advising about that ... I've offered that suggestion to the mods.

Kind Regards, John

 

[SUNRAY]

It really needs 'splitting', rather than 'moving', since the OP and nearly all of the first page were about electrical cable sizing, and plumbers/heating engineers are probably not the best people to be advising about that ... I've offered that suggestion to the mods.

Kind Regards, John

Much better idea.

 

[Harry Bloomfield]

Thanks Bernard, I've been racking my brain trying to remember 'Keston'. IIRC the model will be S followed by the KW rating, so those will have been S30 (I hope I remember that right).

I don't get this bit...

“The MUPVC solvent weld flues designed and supplied by Keston also solved multiple issues, as stainless steel flues would have been too conspicuous and heavy. Keston’s plastic flues were coloured to blend into the brickwork and so are barely noticeable.”

If the flues are hidden in the chimney, why would the need to make them inconspicuous or colour match them?

 

[SUNRAY]

I don't get this bit...

“The MUPVC solvent weld flues designed and supplied by Keston also solved multiple issues, as stainless steel flues would have been too conspicuous and heavy. Keston’s plastic flues were coloured to blend into the brickwork and so are barely noticeable.”

If the flues are hidden in the chimney, why would the need to make them inconspicuous or colour match them?

That's the parts between the boiler and the chimney, once obscured the colour doesn't matter.