I have an old "Ideal" installation and the gas boiler flue pipe has been connected into the existing coal fire chimney. At recent visit by a gas board salesman I was told that I could not replace my old boiler with a new one using the same flue connection and that I will have to have the boiler re-located so it vent directly to the outside ( expensive). What are the rules on using existing chimneys to vent gas boilers?
Venting Gas BOiler through existing Chimney
- Thread starter paulholden
- Start date
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You can't use an open flue system like you currently have if it's possible to install a condensing boiler somewhere else, broadly.
It's down to manufacturers who have come up with oddities - I believe Halstead do a boiler which can use an existing chimney.
It's down to manufacturers who have come up with oddities - I believe Halstead do a boiler which can use an existing chimney.
The number of gas boilers in the BG portfolio is very limited. There are no rules preventing a boiler from being fitted into a chimney flue.
There are gas boilers available that can use a conventional flue, these include models by Kidd, Viessmann, Halstead and ACV.
The installation using the existing chimney would not necessarily be cheaper than relocating the boiler though, if this is your concern.
There are gas boilers available that can use a conventional flue, these include models by Kidd, Viessmann, Halstead and ACV.
The installation using the existing chimney would not necessarily be cheaper than relocating the boiler though, if this is your concern.
I do hope you realize that there is no longer a "gas board". British Gas is a public company which competes for business with every other gas supplier and boiler installer. Provided the installer is a CORGI registered gas installer, you are free to use whoever you like.
British Gas have a reputation for being very expensive, compared with the independent installer, so you are advised to get at least three written quotations. Ask friends and relatives who they have used and get references.
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Halstead do offer this alternative as a plastic flue liner in 10, 20 or 30M lengths. Very expensive though. The adaptor to fit this then makes the boiler act like a conventional flue boiler, in that it takes the air for combustion from the room so still requires adequate ventilation to outside.
There is a company who advertises a flexible flue (twin) to go up an existing chimney, but although they claim it will fit any boiler, I have asked around and as yet have been unable to find a boiler manufacturer who will actually allow its use with their boilers.
There is a company who advertises a flexible flue (twin) to go up an existing chimney, but although they claim it will fit any boiler, I have asked around and as yet have been unable to find a boiler manufacturer who will actually allow its use with their boilers.
completely agree with D_Hailsham.
good sound advice.
good sound advice.
Grant sell one of these (called their 'red system') for use with <90000 Btu Vortexes.
I haven't seen an application yet for gas boilers but it can only be a matter of time and money.
I am not sure where the UK stands on this but in other parts of Europe it is common for the flue to conform to a standard and if the boiler manufacturer says their equipment also conforms, the installer can choose the best solution for the job. As per commercial over here.
Thank you all for replying. I do know BG are independent and expensive and I will shop around - armed with a lot more info than I had before. Thanks again. PH
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