flue in void

[dazzler39]

can anyone confirm whether i can class a Baxi Bermuda Backboiler o/f with flue liner in chimney a/r under t.b008, or not, also a worcester 240 combi o/f with concealed vertical flue , cheers, Darren

[expertgasman]

N0. This only applies to room sealed. Currently.

Ps. Why would you be so keen to do so?

[Nige F]

dazzler39 wrote:

o/f a/r r t.b008, , 240 o/f

To the Combustion Chamber with you

[dazzler39]

Jjust did gas safety on both, baxi operating no problem, no issues, just was aware of flues in voids regs and wondered if this came under those regs, also the worcester 240 was not working so i a.r because i couldnt check safe operation, but the flue disappears vertically into void with absolutely no means of inspecting it, doesnt that come under flues in voids reg?

[expertgasman]

but the flue disappears vertically into void with absolutely no means of inspecting it, doesn't that come under flues in voids reg?[/quote]

Not speifically under TB008. Whether you think it right or wrong, there are loads of non visible flues in voids including many selkirk type flues passing through boxed in voids in bedrooms.

I suspect that this will change, hence my comment : Currently.

I suppose the thinking is that a small opening in a flue is likely to entrail air INTO the flue, rather than let fumes out, whereas a fanned system is under more internal pressure and will surely leak through even a small gap.

[onlyfitidealboilers]

Apart from a flue liner/ back boiler etc. any flue that you can not inspect throughout its length is At risk.

[adlplumbing]

actualy heres one for the mix and i will say it as alowed as manufactirs mi say so
but the new baxi back boiler unit it room sealed and fan flued

[simond]

The TB008 is pitched where the air inlet and outlet are in the same piece of flue. In this scenario, the flue coming apart would result in almost total rebreathing of the products of combustion.

Therefore, in a typical condensing boiler concentric flue in a void, you could go from a normal reading of say 100 parts per million carbon monoxide coming out of the exhaust, to 10,000ppm or worse if it comes apart. Death is almost guaranteed, and an incorrectly supported or fixed flue could come apart undetected by the occupier.

Take the open flue, if there is a leak, CO is released into the surrounding area, but can be expected to be much lower concentrations within a chimney or void, because the air inlet is not likely to be vitiated.

I don't imagine there will be a retrospective directive on open flued appliances, because the implications, whilst certainly dangerous, do not carry the same fatal guarantee as a concentric failure.

[expertgasman]

onlyfitidealboilers wrote:

Apart from a flue liner/ back boiler etc. any flue that you can not inspect throughout its length is At risk.

Is that so? I don't think so, but am always prepared to be corrected. can you point us to where the procedures says this is so?

[onlyfitidealboilers]

Just what iv had off gas safe, makes sense.

[transam]

As I see it any flue with joints that cannot be visually inspected , any open flued boiler would need to be smoke tested if you have X amount of joints lengths of flue pipe built into the infrastructure of the building how would one know they are sound ?? flue liner should be a continous length with in chimney !

Although in many cases one joint may well never be visable were the copex connects to the rigid flue pipe ect , same as some fanned flued steamers that use specific liners , eg Atmos & there flue liner system
(Maybe ?) IMO ect ect

[expertgasman]

I don't disagree that being visible makes sense, or that concealed is a bad idea, but the fact is there are many, many like this and have been fitted as so for years

I haven't seen anything to say that this is automattically officially classed as AR, but equally, I'm sure there are some dodgy concealed joints somewhere.

[mickyg]

onlyfitidealboilers wrote:

Apart from a flue liner/ back boiler etc. any flue that you can not inspect throughout its length is At risk.

incorrect, the TB is only relevant for room sealed fan flued appliances. Open flues are not affected.

[onlyfitidealboilers]

incorrect. you need to inspect a flue through out its length inc terminal its as simple as that.

[picasso]

flues in voids are not at risk until 31 dec 2012, then if no inspection hatches are fitted by that date you can switch the appliance off and label, at the moment they are suggesting co detectors and other safety checks ? whatever they might be.