Strange noise from radiator

[Adam-the-Kiwi]

Hi All,

We've just turned our heating system back on for the winter - boiler is a Baxi Combi 133HE Plus. All the radiators seem to be heating up as expected and, as yet, none appear to need bleeding. This morning, however, we noticed a fairly loud buzzing coming from the bathroom - the radiator was vibrating and this appeared to be the source of the noise. The radiator in the adjoining bedroom was also vibrating, but much less so. The noise appears to be linked to the pump, but the boiler itself does not appear to making any unusual noise.

Can anyone give me any suggestions as to the cause?

Cheers - Adam Cheney

[The Natural Philosopher]

sounds like vibration from the pump via the water to the radiator.

May be the first sign of a failing pump?

[Adam-the-Kiwi]

-88-

-88-

Thanks TNP - I hope not, as this boiler is only 18 months old...

[The Natural Philosopher]

swarf in the pipes can lead to early failure..

All installations have an inverse valley shaped reliability curve.

In the first year installation and manufacturing defects show up. After that they are reliable until the parts age...

[EricP]

When you say "buzzing", was it a metalic hammering? Rather like an ant tap dancing in lead clogs?

If so, you have TRVs and they are on the wrong side of the rads.The closing valve is vibrating as the water flows over it.

Have you had a new pump installed or turned up the flow?

[Adam-the-Kiwi]

-88-

Hmmm - it's a little difficult to say, but I'd definitely describe this as a low frequency buzz rather than a hammering.

No and no. The system was working fine last winter, and we've only just turned it on for this winter.

Cheers - Adam...

[Dave Baker]

Try changing the speed on the pump. They are usually two or three speed and a lower one for a while might let things settle down. Probably just a sympathetic system vibration from the pump which has altered over the summer as pipes have furred up or sediment has settled somewhere.

[Adam-the-Kiwi]

-88-

Thanks Dave - I'll give that a try (if I can work out how to do it)...

Interestingly, a hefty thump on the radiator in question has changed the intensity of the buzzing.

[Harry Bloomfield]

Adam-the-Kiwi presented the following explanation :

That sounds as if it could be a TRV or valve vibrating.

[.]

agreed.

[EricP]

Ok, go to the lockshield valve on the other end of the rad and close it completely and then open it half a turn or until the rad works again. Keep opening it a half turn until the noise returns and then close it until the noise stops or reduces.

[Adam-the-Kiwi]

Apologies for the delay in responding...

That did it - thanks.

Cheers - Adam...