In article ,
cynic writes:

I'd be looking for a problem with the wet stuff. Is the reflled system
dosed correctly?
You may care to try some "boiler noise silencer"

I doubt it's dosed at all - it still has to be drained again
(next week I think) to connect two more radiators on. The noise is
far too uniform/regular to be kettling. I'll see if I can sense
the vibration on the boiler pipework next time I visit. As I
said, there was none detectable at the pump, but that's quite
distant from the boiler.

--
Andrew Gabriel
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