Thanks for the reply, it begs the question, which part of the flue is the
outlet and which is the air intake?

"Andrew Gabriel" wrote in message
...
In article ,
"Graham Jones" writes:
I was wrong, it is leaking from the boiler but intermittently. Maybe
condensate then?

Could be condensate or water from the heating system.

Condensate is relatively corrosive, so steel metalwork it
comes in contact with rusts quickly. In time, it can corrode
through sealed casings, rendering them unservicable.

With my Keston, I check for leaking condensate by leaving the
hosepipe trickling slowly into the end of the flue outlet. The
water should pass through and away down the condensate drain.
Make sure it is (don't let it fill up the heat exchanger or it
will likely damage the ignitor and gas parts). Make sure you don't
run water into the boiler air intake instead of the flue outlet.

I don't know how suitable this test is with other condensing
boilers. Boilers which pump out the condensate might not do so
when the burner isn't firing or the power is off for servicing.
At your own risk, as they say.

--
Andrew Gabriel
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