Worcester 30 cdi - noisy Central heating

[lvegas2009]

I have a Worcester 30 cdi boiler which was installed about 18 months ago.

For the last few months, I have had noise from the central heating when it starts up and switches off. The noise is a "pinging" and "clicking" and is heard for a few minutes while the heating warms up. Once warmed up, I get the occassional click and ping but that sounds just like normal pipe expansion. Noise is most noticeable upstairs. The noise is sufficient to wake me up every night and is getting increasingly annoying!

The boiler was serviced in the Autumn, but heating not used for a while after, so do not know if this has caused a problem? I do not remember the noise occurring the first winter we had the system, nor on the old Ferroli system we had before so believe something has changed.

Initially thought there was something stuck in a rad, but after removing the one I thought the noise came from, there was nothing unusual. There did not appear to be much muck in there, and we have an attached Magnaflow.
One small thing, I do occasionally here a noise from the boiler which sounds like the noise when you blow across the top of a bottle? Do not know if this related or unusual?
Any ideas greatfully received. My guesses are:
-leak in system/pipework
-pump speed changed? (Don't know if this can be adjusted, there seems no setting on the display or user manual?
-muck in system (seems unlikely? System was powerflushed when installed and the magnaflow currently shows little in the way of muck?)

Any help / suggestions gratefully received

 

[mfgs]

Could be the rads moving on the radiator brackets. Did the brackets have plastic covers where the radiator sits on the bracket?

 

[erpkid]

Sounds like kettling. I would get an engineer in to check the boiler over.

 

[lvegas2009]

Thanks for the suggestions

The rads are quite old and never had plastic covers on brackets, so I don't think it is this.

The boiler seems to sound "normal" and is relatvely new. What are the symptoms / giveway that it could be kettling? Presumably if it had been flushed when system installed this would reduce most mineral deposits?

 

[mfgs]

I have had the noise with old rads, a newer boiler heats them up quicker and the faster expansion of the metal makes the sound. Without hearing it, it is very difficult to say.

 

[lvegas2009]

Please do you know if there is a way of altering the pump speed? Wondered if the boiler was "too powerful" for the system?

 

[ambrosia]

is it an external pump, have a look on top to see if theres a switch with 3 speed settings, but obviously remember which setting its on in case for have to change it back

 

[AMGasServices]

It could be undersized pipe work. The core pipes could be in 15mm rather than 22mm.