Neighbor's boiler / flue waste gases enter my flat

Jeepers_Creepers

Each flue will need its own extension, and there's a limit to the length they can be (but no idea what that is).

In your last photo, I take it that's your balcony on the left which has the blanket draped on it? And it never occurred to the fitter that having a plumy flue exhausting immediately under it could possibly cause a nuisance?! He knew, all right, but just didn't want the hassle after having done most of the work.

I'm not sure what options there are to divert that flue, as even taking it sideways along that side wall and upwards will still likely have the fumes coming across your balcony. But that's their problem.

As far as you are concerned, it's not for you to come up with solutions, but just to tell them it's unacceptable. Whenever I walk down the side of our house and the boiler is running, I am very aware of the smell, and the visible plume - especially in chilly weather - is unavoidable. In addition, when the boiler fires up there's a momentary whiff of unburnt gas. Not a prob as it's down the side of the house. But coating me if sitting out on a balcony or having it come in to the house? No, not acceptable.

Guess what's doubly-unacceptable? Yup - a neighbour's flue doing this!

Where did the old flue exit?

unforeseen

Where did the original flue exit the flat? Under your balcony? 

Chanterelles

unforeseen said:

Where did the original flue exit the flat? Under your balcony? 

Inside/under the balcony, like 10 cm long

unforeseen

So putting it elsewhere would mean a change in the boiler location. As there appears to be only 2 outside walls, there is not a lot of choice. 

macman

Why don't you just speak to your neighbour initially? Involving EH or the HA at this point is not necessary.

macman

Chanterelles said:

@missile, it is not gas smell, it’s more like a very faint car exhaust sort of smell. And as I understand, boiler exhaust is toxic because it contains carbon monoxide, right? That’s why it has to be going away from the windows. 

The majority of flue gas is water vapour and carbon dioxide (the same gas that you breathe out). Carbon monoxide is a result of unburnt natural gas, which should only be present if a boiler is badly calibrated or faulty.
Have you got a CO meter near the source?

Ectophile

Chanterelles said:

And am thinking everyone in this column of flats should agree to extend the flues and connect to something that takes the discharges up to the roof if this is what needs to be done to avoid further issues. ?

Boiler manufafcturers will specify a maximum length of flue pipe that their boilers will work with.  Extending the pipe up to the roof will almost certainly exceed that, especially as every right-angle bend reduces the allowable length.

unforeseen

For 5 storey block then I doubt a vertical flue is possible.
 Baxi can do a total length of 10m and Worcester is 6.4m as examples. The  length is reduced for every 90 or 45 deg bend plus it has to extend above the roof by a certain amount as well. 

molerat

unforeseen said:

Where did the original flue exit the flat? Under your balcony? 

Looking at the photo there is a short flue sticking out of another flat.

Jeepers_Creepers

So the original flue exited right on to their balcony? That must have been pleasant!

If you look at the new flue, that smaller central pipe is the exhaust, so the extended pipe will be that diameter. I guess it can be elbowed around that corner and led away along the flat-owner's wall - past that black vertical vent pipe - a metre or so before then aiming outwards to exhaust there?