Boiler flue terminal permitted locations

5 Oct 2010
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United Kingdom
I am considering possible locations for a wall mounted boiler. Ideally, I want the boiler installed next to a window on my kitchen wall. The potential problem is that the hole for the flue terminal would be just 200mm measured horizontally from the opening portion of the window.

My understanding from the relevant gas regulation (taken from that common diagram of permissible flue locations) requires a minimum horizontal distance of 300mm between opening window and flue termination. So if the flue terminated virtually on the outer wall surface then gas regs would clearly be contravened in my situation. If however the flue termination was made to project far enough beyond the outer wall face, this would allow the horizontal distance between flue termination and window opening to increase to the required 300mm.

Using Pythagoras' Theorem, by increasing the flue termination to 224mm in front of the wall surface would result in a horizontal distance of 300mm between window opening and flue termination, with the flue hole 200mm from the opening.

This would allow me to get round the problem, but can anyone confirm whether I am misinterpreting the regs, and in particular the disctinction between flue terminal and flue termination for my situation?
Sponsored Links
You don't need Pythagoras' Theorem. Just a plume management kit.

I may not even need that, once I know whether the 300mm minimum refers to the end of the flue, or the flue iteself!
Sponsored Links
the 300mm refers to any part of the flue but as already advised use a plume management kit for the first fix then in most cases the distance is reduced to 150mm, but at the end of the day who is really going to care unless you need a completion certificate from your LBC, yes you might get a NTC notice from RGIs working in your property but the clearance police are hardly likely to come running

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