Combi boiler noise

[alfie jones]

We have a new gas combi boiler.  Although not on timed for heating etc, every 45mins or so, it "fires up" for a couple of minutes and in doing so something makes a loud noise like a fog horn for 4 or 5 seconds.

Whilst this is not much of a problem, its bugging me as the old boiler (which was identical to the new one and only replaced due to a fault) didn't make the noise.

Any ideas what could be causing it before we approach the engineer? 

[bascca]

hi what make and model boiler is it. if it is a new condensing combi it could have a pre heat or eco setting which will fire the boiler very so often to pre heat the hot water. the noise could be the fan, does it do it on heating?  

[bascca]

ps i am corgi registered

[Kos]

If its new then you might as well get the engineer back out to fix it- it must be covered by some sort of warranty

[firefly1000]

I have same problem with a Vaillant 828 that I had installed a few weeks ago. Happens every time it plumes and fires up. Only lasts about 5 seconds and not that often at moment. Im guessing that it will become more frequent when the central heating is used in the Winter. Would like to sort it now if poss as the noise is annoying. Ive had the Engineer take a look but he says he cant work out what it could be. Have you resolved it yet ?

[pgj99]

I have a simlar problem to. A sort of roaring sound. I think that the flue must be filling with gas and the igniting. That the sort of sound it is, not sure how bad that is but it really shakes the floorboards :) Is there a simple way to stop this?