Gas boiler help - what is this sound?

[RachyWoo]

Not sure if this is the right forum or if it should be in "off topic". But anyway, if I pull out any more hair over this I'll be bald!!!! Does anyone know any gas men who would have any idea what the heck this noise is? Or has anyone had a boiler do this? It can do it when the central heating is on or just when it's heating the water up. We've had numerous gas men visit but because it never does it when they're here, they have no idea what it is and whatever I query, they say it can't be that I have my suspicions of what it could be, but I'm interested to see if anyone thinks the same.

 

[spiderpig]

What do you think it is? I can show my partner the video later with your thoughts and see what he says

 

[RachyWoo]

That would be great, thank you. I think it's either the circulating pump or the heat exchanger. The radiators start off so hot you can't keep your hand on them and then there's a reduction in heat as the day goes on. Then the boiler starts clicking on for 10 seconds and not heating the radiators, or it doesn't click on at all for over an hour despite the radiators being stone cold......if any of that extra info will help him. All the engineers that have visited are baffled because they said they've never heard anything like that before and said they cant really do anything until it does it when they're here It never does it when they're here though!

 

[spiderpig]

Ok will ask him when he is home

 

[RachyWoo]

Thank you

 

[Tor88]

That sounds like your fan. Had numerous problems with mine and the sound was very similar. Fan or bearing may have gone and need replacing. I’ve also had a broken heat exchanger that made no sound at all so I don’t think it’s that but obvs I’m not a gas man.
Pretty sure I’d the fan can’t turn etc then it won’t heat radiators. If it’s is either the heat exchanger or fan I think it’s around £80-£100 for parts plus labour

 

[RachyWoo]

They put a new fan in last month, so it's not that. It's a total mystery at the moment.

 

[Tor88]

Oh wow. I know when we had a new fan the noise continued and they can back out and the expansion vessel was full of water which causes the fumbling sound so they emptied and repressurised. Has anyone looked at that?

 

[RachyWoo]

Oh right, I wonder if that's a possibility then. I've no idea if they've done that actually, I'll mention that to them.

 

[Tor88]

There’s a few videos on YouTube of a faulty expansion vessel and I think the noise is similar to yours. Worth a look, especially if you’ve had recent work carried out

 

[RachyWoo]

I'll have a look at those. Thank you