On 31 Jul 2003 12:25:19 GMT, (Andrew
Gabriel) wrote:



Yes. Some of it was bull****, but I wanted to hear it so I
didn't try and correct anything.

The main reason was lack of reliability and expensive repairs.
I can't argue with that -- I don't have the necessary data.
Bloke behind the counter said one of the manufacturers was on
fourth redesign of condensate drain in a year and third redesign
of something else and someone else's heat exchangers usually
failed just after warantee and cost over half the cost of the
boiler, and the tale of woe went on.

Certainly the heat exchangers are an expensive item, but perhaps this
is an issue of manufacturers building to a cost and price point.
When I was selecting, I eliminated all but stainless steel exchangers
for that reason.
I also asked each manufacturer for an extract from his spares
pricelist of the 10 most expensive items. That was quite revealing
and weeded a few vendors out.


Basically, after fitting,
they have to keep going back to sort the boiler, which gives the
fitter a bad name, so they don't fit them. I asked specifically
about the Keston (which I chose) and Ariston (which I looked at
because it was the smallest one made). There was some agreement
that Keston was probably as good as you'd get now, but ones
which are 3 years old are badly suffering failed heat exchangers.
Then a comment that whilst it used less gas, it had a 1kW fan
in it bull**** alert so it just used more electric instead.

I wonder how on earth they worked that one out.


They were very scathing of Ariston's, but I can't remember why.
Also, I presumed from this conversation most gas fitters don't
have a flue gas analyser (and when I spoke to Keston, they also
assumed the gas fitter wouldn't have one). Reading between the
lines, this is why they can't commission or service them.

I think that's exactly it. IIRC from reading Keston's manual, they
supply the boiler preset and suggest that the fitter works out the gas
rate by timing the meter. They then go on to suggest that the CO2
level is measured to be sure, and of course that needs a flue gas
analyser. They then suggest that the fitter calls them if there are
problems.

On the MAN boilers the procedure requires a flue gas analyser since
the pressure test point that would normally be used on the burner side
of the gas valve is actually at negative pressure and not meaningful.
There is a procedure with a special test button that is used to allow
the CO2 level to be checked at minimum and maximum burn rates, there
being an adjuster for each. It is iterative, and takes a couple of
goes at each end to get right. The the CO level is checked at each
point.

I bought a flue gas analyser in a special introductory offer that BES
had last year. Even if I only use it once a year when servicing and
cleaning the boiler it pays for itself in two years.

I would have thought that any decent fitter should have an analyser as
well - there's really no excuse. Since one of their roles is to look
out for excessive CO emissions in an appliance, this is important
anyway for servicing. Looking at the flames is one thing, but AIUI
only shows relatively serious problems.


So, what are the issues?
I can believe that boilers based on conventional technology
which has matured over very many decades are probably more
reliable than boilers based on new technology. There seems
to be a problem (or at least a believed problem) in condensing
boilers not lasting out or very far past their warantee period
without expensive repairs required.
I suspect gas fitters have been using the same traditional
brands for condensing boilers which they use for conventional
boilers, and it seems to me those brands probably aren't the
best -- they certainly entered the game late.

Exactly. About 15 years late. The loyalty incentive programs are
pretty inviting as well.

Gas fitters are conservative (which is not unreasonable when
your salary depends on it) and/or gas fitters don't understand
condensing technology.

This is a shame.


..andy

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