Conventional Boiler vibration

[Tracnation]

Hi there,

Looking for some help on the cause of a vibration in my Ideal WLX RS60 conventional boiler. Over the past week i've noticed a slight vibration noise that started off in a radiator before moving to the boiler and now effects the two radiators closest to the boiler and the boiler itself. It doesn't appear to be coming from the external pump which is pretty silent. The noise was actually so loud this morning from both the boiler and the radiator closest to it that i thought it was going to blow. Oddly the heating wasn't actually on this morning only the hot water.

Any ideas what would cause this? The radiators were all bled a few months ago and till last week there was no other issues.

Many thanks
Neil

 

[Tracnation]

Quick update.

The noise which I initially thought wasn't kettling turns out almost certainly is. The noise now starts within a minute or so of the boiler kicking in and the entire system is red hot including the boiler housing pump and radiators. I've turned down the thermostat on the boiler which does cause it to cut out quicker but doesnt stop the noise and the pump appears to spin fine with no unusual noises.

I've read the main cause of kettling is limescale but I live in a soft water area and have no such issues so dont believe that is the cause. Is there anything else that could cause the issue?

 

[Spark74]

The wife's magic eggs?

 

[45yearsagasman]

Try adding some "System Silencer" via a rad. Fernox or Sentinel are a couple of brands.

 

[Tracnation]

Hi thanks for the advice.

I've put fernox f2 in but hasn't made any difference.

One thing iv noticed though is the boiler doesn't appear to be taking water from the expansion tank nor does it appear to be venting into it. Could this be the problem and if so what can I do about it?

 

[45yearsagasman]

How did you put in the F2?

 

[Tracnation]

Via the radiator closest to the boiler.

 

[45yearsagasman]

The noise which I initially thought wasn't kettling turns out almost certainly is.

My advice was based on your info. Obviously your diagnosis was incorrect. Very difficult to diagnose noises from behind a keyboard.
Under normal operation the vent pipe will show nothing. You can check if the feed is blocked by partially draining and checking the water level in the tank drops and tops up the system again. You won't waste any F2 if you collect it in a bucket and reuse it.

 

[Tracnation]

Thanks again for replying.

Usually when I turn on the heating it's like a waterfall from the tank into the boiler but for the last few weeks there's been nothing but silence until the noise starts.

The f2 may have actually silenced it a little now that it's been in for 12hrs but iv 7 single radiators and 3 doubles so might need two doses.

The noise itself starts around 30 seconds after the boiler fires up and starts off like a slow quiet ticking and gradually gets louder and faster till the boiler shuts down then it slows and stops after about 10 seconds. When the pump runs without the boiler fired there is no noise. It does appear to be heat related though as the pump housing pipework are all so hot that you can't hold them for even a second without scolding yourself which was never the case before even after only a few minutes of running.

I've never been able to find the drain point on the system but I think it'd hidden under the garden decking which would mean ripping it up.