Rattling Boiler

[RJH]

Can anyone identify this noise? -

It's a sort of high pitch metallic rattling, happens all the time, and has started since I drained and refilled the closed combi system.

[Harry Bloomfield]

RJH explained :

Water circulation pump, if it has one fitted inside the case, fan, or simply something inside the casing loose and rattling.

[rmlaws54]

Is there an air vent on the water circulation pump? Maybe it needs bleeding. If it's an automatic one (with a float inside) they sometimes clog up with limescale.

Robert

[RJH]

Thanks, yes, tried bleeding the pump. No limescale here, so the mystery deepens.

[RJH]

it doesn't seem to be from the pump, more higher up in the boiler, maybe the fan area. No obvious cause of rattles. FWIW, a couple of pics:

[Brian Gaff]

That is definitely a loose something. it does not sound like its inside any water containing parts to me. It could of course be almost anything. The boiler sounds pretty noisy to start with, was it always that noisy? If not you might have an issue and it just happens that its making a piece of metal vibrate. Was the pump unseated or moved. Often the mountings have a lot to do with the transfer of vibrations to the structure and the loose bit you hear might have always been there. Brian

[Brian Gaff]

Not sure if its operatable with any covers off etc, but a stout pair of gloves and prodding things might show something up. Brian

[RJH]

That's at its noisiest, and the recording has been amplified considerably. It's not actually that noisy in use.

Couldn't see anything obvious. Some wire looms loose. But it'd take a lot to create that sound. Another step is as you suggest - fire up without the cover on - building up to that :-)

[Harry Bloomfield]

RJH brought next idea :

You will be OK with just the outer cosmetic, none sealed panels off. Under that is a second room sealed panelling system, with out which it should never be run.

[Brian Gaff]

Hmm, the number of devices I used to run with covers off is in the hundreds. Of course a lot of the covers inside a boiler are there for safety and airflow reasons. However if one can localise the vibration and poke it with a plastic knitting needle to be sure then you can power it all down and fix it. The most annoying one of these sort of things was a tumble dryer that squeaked, but only when the covers were on.That in the end turned out to be just a belt, though to this day I do not understand why it sounded as it did.

Old age in equipment does many odd things, as does disturbing things that have been ok for years.

Back in the old days of the first colour TV sets, we had one that would whistle very loudly sometimes and not others. That turned out to be a coil on the timebase boared not vibrating at the real frequency it was using of course, as that is beyond hearing but some lower frequency agitated by the higher one. A blob of quick setting araldite fixed it. I'd not want to have been the engineer trying to remove it from the pcb later on though :-) Brian

[Mr Pounder Esquire]

Top posted for Brian. Our 14? year old Creda tumble dryer in the garage sometimes make screaming noises when used. The next time(s) it is used the noise is normal. I do not understand this. I once tried to take it apart to check for fluff and gave up as it was a nightmare. I did the best I could with a Dyson sucking the fluff out.

Brian Gaff wrote:

[tabbypurr]

sounds like a bearing that will seize at any moment

NT

[RJH]

The panel is sealed with a gasket - but I wouldn't have thought it's air tight. Taking that cover off reveals all the components - there is no second panel (see the pics above).

[Mr Pounder Esquire]

Yes. But. This is been going on for a good 18 months. I'll wait for the inevitable failure with a load of washing to dry.

[RJH]

Ahem, found the cause - it's the casing of the pressure gauge vibrating against its plastic cover. Think I'll just leave it for the time being

[Harry Bloomfield]

Maybe push a bit of sponge between the two surfaces, to damp it.

[RJH]

Thanks - just tried. All the noise seems to be generated from within the gauge. Wedging some rubber stuff in changes the pitch a little.

I'm inclined to let it fail and replace as needed (£40) in the hope that nothing catastrophic happens meantime.

[RJH]

Quick update - I've come across this now and it seems to be a 'design flaw' - one fix is blu-tack!

The other issue I've had with this Ideal Logic is the mains water inlet joint. Looks like large compression fitting to me. The installer said he's had to replace several - I've needed to pinch-tighten it a couple of times over the years.