Gas boiler question

[Conna]

Hi all,

Over the lase 3 weeks or so we have been hearing a strange noise like a Puffy sort of bang. We ascertained that it was coming from next door but this morning as I was up very early I heard it again and it was quite loud I decided to investigate it. What I saw worried me a little, where the flue comes out of the wall to go outside is between my Conservatory and next doors extension, a gap of about 3ft, there is a little whirring noise which dies down and then starts up again and when that happens that's when the bang occurs and a small blue burst of flame expells from the flue. IS THIS NORMAL? or is the house about to blow up? I don't really want to go round next door and cause a fuss for nothing so I thouht I'd ask on here first.

Thanks.

[Terry D]

I suggest that you have a word with your neighbour as a matter of utmost urgency and insist that they turn off their gas supply and call out a CORGI registered gas engineer. If they take no action, call the National Gas Emergency Service, who would probably send an engineer to isolate their gas supply. It's just not worth taking any risks where gas is concerned.

Terry D.

[AW]

If you are seeing a blue flame then there is raw gas getting out and mixing with outside air. Don't you remember the demonstration in chemistry at school where a small coffee tin had gas fed into it from a pipe below, the gas was turned off and that escaping from a small hole in the lid was lit; when the gas/air mixture got to a certain level there was a bang and the lid of the tin came flying off? That is exactly what looks to be happening in the flue.

As said above, get a fitter or the NGES there a.s.a.p. - NGES is on 0800

111 999 - they have a Statutory Right of Entry if your neighbour is awkward.

[Andrew Gabriel]

Boiler is probably suffering explosive ignition. This can happen for a number of reasons, but mainly coming down to needing a service. The boiler is taking too long to light, and filling with more gas/air mixture than is good for it before lighting, so the ignition is explosive. This could be dangerous, quite apart from the harm it may be doing to the boiler and flue.