On Nov 13, 11:31*am, YAPH wrote:

So a mechanical system that's faulty now was OK a year ago. Why is that a
puzzle? If your car's OK now does that mean it'll still be OK a year from
now?!

POint taken, but I wouldn't normally expect pipework to suddenly start
leaking unless it had been worked on or hit. The leak is not in the
boiler (the only applicance).



0.01mBar per second (if that's correct) equates to a drop of 1.2mB over
120s which is within the allowed tolerance for a standard meter and
standard domestic pipework, if appliances are connected.

Yes, it was 0.1 mB/sec I watched the display of his meter.

What's the drop with the boiler isolated?

exactly the same.

If it's within tolerance (no discernable drop) with the boiler isolated
then the drop is within the boiler which is OK, though you'd want to check
the gas valve (I'm assuming it's an old boiler) and internal boiler gas
pipework to ensure there's nothing actually leaking in there.

If it drops with the boiler isolated then you need to find and fix the
leak. First port of call is always the hose connecting the test instrument
to the gas meter test nipple :-)

That's what I suspect also, especially as it gave an OK result at
first and then started to drop. However, his first port of call is to
disconnect the parts of the pipework that lead to terminations that
don't have appliances on them.

We are getting the original plumber aback who did the previous test
(and some pipe works).

Thanks for your guidance people.

Robert