On 21/10/2013 21:17, Clive George wrote:
On 21/10/2013 19:01, Peter Crosland wrote:

That brings us back to the 'competence' problem of not being defined.
Just because a building blows up it doesn't provably mean that
anything about the installation process was incompetent or negligent.
Boilers, etc, carry warranties for this reason.

After I had my previous system installed, a leak developed in the
joint on the supply side of the meter, which the installers hadn't
touched. Buildings blow up for reasons other than lack of competence.

Of course not but that is not the point. Anything burning has an
inherent risk of danger. Explosion is only one of the potential dangers
that can occur by incompetent work. There are far more common risk of
poor combustion is CO poisoning. Do you think it is acceptable to put
people's lives at risk by trying to save a few pounds?

Which is the higher risk : DIY done competently or professional done
incompetently? There's plenty of examples of the latter in this thread.

This stuff isn't magic. It's entirely feasible for somebody to DIY stuff
competently.

I have never suggested otherwise. In the case of the OP the way he
phrased his question suggested he lacked the necessary expertise. The
rule really is if in doubt don't. As for risk that is an impossible
answer to give a statistically valid answer to. Having said that no
system is perfect and we only tend to hear about the disasters
regardless of who caused them. Logic would support the view that a
properly trained person who does a job diligently is much more likely to
do the job competently than an untrained over confident person.


--
Peter Crosland