noisy central heating boiler

[Explorer-8]

My neighbour has a noisy central heating boiler (which I think is a combi boiler). It sounds like a small aeroplane flying in the distance (or like a pre-war aeroplane). What could be wrong with it to make such a sound?

[Muppit]

Perhaps the bearings in the pump?

[gucciman]

best guess without examining it in person is the fan on the boiler is off balance and scraping the fan housing. could possibly also be the case on the boiler is loose and is resonating.

[Explorer-8]

Thanks Muppit and Gucciman. With either of these possibilites, could it be that the boiler can't survive if these problems (either the bearings or the fan) aren't sorted out? If it is just the boiler case, I can't imagine it being a problem apart from the noise. Sometimes the vibrating sound changes pitch before it stops.

[eltelioni]

It will be worn bearings on the fan. The resulting looseness will cause the vibration you describe. Mine does this, though it is not bad enough to disturb the neighbours. The bad news (good news for you) is the vibration is putting extra stress on the bearing and it will eventually give up.

[gucciman]

agreed, it will either sieze or/and burn the fan motor out or blow the fuse on the boiler.

[eltelioni]

Maybe I should get mine fixed soon ....

[Explorer-8]

Thanks everyone. The sooner their boiler packs up the better and the sooner I will be able to sleep in after I've been working on the late shift instead of being woken up by that racket.