Brian Reay wrote:
On 17/12/2017 10:08, Dan S. MacAbre wrote:
Last time I looked inside our old Thorn Apollo (either the
thermocouple ot the top socket needs replacing every five years, or
so) when I took the inner metal case off, it looked like water had
been running down the inside for a long time. My first thought was
that the heat exchanger gaskets needed replacing, but our CH water is
usually dark brown (even though I put inhibitor in every other year),
and there was no brown stain as usually happens on the odd occasions
that our CH water manages to escape. But I can't imagine anywhere
else that it might come from. Is it normal for the gaskets to need
replacing after 30 years? I wouldn't be surprised. Could it be
condensation? We've started to go to Rome every February in the
school holidays, but I'm not sure that the pilot light would cause
that much moisture, given the ventilation from the flue.

I'd think condensation is unlikely- you need a cool surface. I'd be
surprised if even the case was cool enough.


Me too, but that's why I mentioned we were away for a week each
February. It's pretty cold by the time we get back :-)

I'm afraid, given the age of the beast, I'd suspect a leak. Hopefully
not in the exchanger (been there).

In the past, I've seen different colour (or no colour) to the trace left
by leaks in a system. I'm not sure the lack of colour is significant.


I think I'm just going to have to wait until it's really obvious where
it's coming from. Like crusty deposits building up, or something. Or
maybe run it for a day with the boiler off. Too cold for that now,
though :-)