condensing boiler making v.loud high pitched noise when operating

steve1471

My central heating condensing boiler is making a very loud high pitched noise randomly when it is operating. it is very loud and sounds similar to the noise you get if you blow across the top of a bottle.

The noise can last anywhere from 1 minute to 4 or 5 minutes. I notice that when its making the noise the display on the meter speeds up by 4 or 5 times suggesting its suddenly burning more gas ?

This noise is not all the time but will come and go for random durations if the water or heating or both is switched on.


[FONT=&quot]In addition it seams to turn itself on for random time/duration also ?[/FONT]
The boiler is insured , however i would really appreciate some advice on this before the engineer turns up.

[FONT=&quot]many thanks in advance[/FONT]

roswell

is the waste pipe outside frozen?

is the pressure right ?

steve1471

hi

thank you for the reply.

the waste pipe is not frozen.
i dont know what the pressure should be or how to check it unfortunately.

Im not sure but it seams very strange that it burns much more gas when the noise is happening. i.e. i can see the meter wheels turning , where as in normal operation they appear to barely move.

macman

Make and model would help.
Is it a combi or conventional boiler? If it's a combi, what pressure is showing on the dial?
Are you saying that it only makes this noise when the boiler is actually firing (i.e. when the burner is lit?)

amcluesent

Could be the motor/bearing on the flue-fan is knackered that causes the occasional screech. That's £200 to replace.

Sheepfan

Hmmm - I've noticed the exact same thing happening to my combi boiler over the last 6 weeks. It's a Glowworm Flexicom 35, just over a year old. Like the OP, it seems to happen at fairly random times.

My waste pipe joins the main waste in the basement of my house, and I'm pretty sure it's not frozen (and it certainly wasn't when this started happening weeks ago).