I've recently moved into a newish (2007) property which came complete
with an Ideal Icos H15 heat-only boiler. By many accounts it's not the
best of boilers but it seems to fulfil our needs and is working well…
well almost…

I can hear what you might describe as a 'ticking' sound from within
the boiler. If I was to hazard a guess to its source I'd say it was
either the front panel controls or, perhaps more likely, the main PCB
control board which is located behind it. The ticking is similar to
that from the constant background noise of a mechanical washing
machine timer or similar wind-up clock.

The noise is constant i.e. occurs regardless of whether the boiler is
sat idle, fired up, post-firing etc. I'd say the frequency rate of the
ticks is around 8 per second.

Given that the noise occurs in its idle state, and I am not aware of
any moving parts that could account for it, I am at a loss as to what
the problem, if it is a problem, might be?

Can anyone shed and light or offer some thoughts as to what it might
be? As I say, the boiler 'works' but I just can't help thinking that
this isn't right and whilst far from intrusive (I'm the only one
that's noticed it) I do wonder if it's a telltale sign of impending
doom and so with winter round the corner I'd rather be ready to tackle
it sooner rather later. I am also curious as to what it actually is
i.e. if it is the PCB what component could cause such a noise? (This
is more out of curiosity rather than wanting to necessarilly effect a
board repair)

More than happy to provide further details if required.

Regards,

Mathew