Valiant Flue extension question.

29 Sep 2011
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United Kingdom
Any help on this appreciated!
I'll start by saying only a qualified fitter will be doing this, if it's possible.

I'm getting conflicting information on extending a flue from a Valiant Turbomax gb242e. Currently the boiler's flue exits at 90 degrees from top of the unit through an external wall, a very small distance.

Building work will mean that where it now exits will be inside a new kitchen build so we need to turn the flue another 90 degrees and extend the flue upwards to exit via a new roof being built. This would mean a flue extension joining the exsisting flue.

Is this possible /legal? To join two 90 degree extensions so we can exit via a roof?
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You will need to remove the horizontal terminal from the elbow. Replace it with an extension piece. Add another elbow then run it up through the flat roof and terminate with a vertical terminal.

The precise lengths you are allowed to go are in the manual.

This is the model with the black font and green dials? If it is the newer one I would just bin it and start again.
Yes it's the model with the black panel and green dials. It's been a great boiler so keen to keep and not have to even move if possible. I'm looking for the info on the extension length.
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The flue parts will cost you over £200 alone. And they are not compatible with a modern Vaillant, sohen you replace the boiler, start again.

Frankly if you are staying in the house for any length of time you would be better off binning it and starting again. The economic lifespan is already nearly reached on this boiler.

Finally when rerouting the flue, bear in mind tech bulletin 008, which requires EVERY flue joint to be inspectable on an annual service visit. There are no dispensations, if the joints can't be seen, it is turn off time....

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