Question about number of Flue bends

6 Aug 2011
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United Kingdom
how many right angle bends can be used in a flue for a condensing boiler

due to the loaction of the boiler means the flue needs to be routed out through 3 right angle bends with a total length of 2m.

the boiler will be a budget priced combi boiler ideal standard or similar for about 500 quid, or thereabouts ,

The flue cannot be placed directly outside the wall where the boiler is located, so 3 right angle bends will be needed.

(PS. Don't be paranoid, I am not doing the installation myself, but a qualified installer will and he has suggested that I relocate the boiler where the flue can be taken out directly through the wall with no bends, but then this brings in more complications for plumbing, meaning there is no direct connection for condensate discharge and the condensate pipe will need to cross a door way, so my plumber (installer) suggested using a condensate pump, to pump the condensate over the door, but also the new loaction means both cold and hot water pipes as well as the Gas pipes will need to be reloacted, and so more work and more costs and i don't want pipes running underfloor.)

Currently the house uses warm air heating, so this is being phased out and replaced by a wet radiator CH and a combi boiler.
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have look on ideal website all the installation instructions are there
thanks for your response and direction pointing, I did further googling and came up with a 6 year old thread that is exactly what my problem is and now I can see from it that it can be done, depending on the boiler manufacturer's specifications rather than being governed by gas law.

I could persuade my installer to possibly run the flue with a couple of right angle bends, as long as it is within the gas regs and safe and practical, and i hope he doesn't get the hump with me for suggesting this more convenient location as opposed to what he suggested.

He could run the flue from the boiler mounted on the left wall of the utility room and run it across just under the ceiling, to about the opposite wall 5 feet across , and then using a 90 degree bend turn it right and out through th external wall and terminate it outside, maintaining minimum distances as reccomended by flue rules from any nearest opening or the neighbours wall.

since the flue will run mostly within the utility room, a flue cutting across, mounted just under the celiling and then out through the external wall, wouldn't bother me looks wise as long as it is practical and safe.
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