"sro" wrote in message
...
"IMM" wrote in message
...
"Ed Sirett" wrote in message
...
Andrew Gabriel wrote:
In article ,
"sro" writes:
Am I being unrealistic - are all modern devices complicated and
unreliable ?
:-)
Yes. By turning such products into consumables rather than capital
purchases, the manufacturers keep themselves in business.
OTOH, such products are vastly cheaper in real terms than their
older long-lasting predecessors.
I seriously doubt you'll get 18 years out of any current boiler
without some major parts breaking. I also seriously doubt any
manufacturer will supply spares for anything like 18 years.
Once a boiler has had a small water leak for a while the corrosion and
associated problems seem to send it on a downward path.
This is a straw poll of the boiler failures for which I have ended up
replacing the boiler (often with a Vaillant Turbomax+ 824e).
1) Saunier Duval combi - poor HW perfomance very noisy. about 10 years
old.
2) Ideal Mexico - floor standing CI - 25 years old?
primary circuit corrosion leading to heat exchanger failure due to
indirect coil leakage.
3) GlowWorm Space saver - 22 years old - refurbishment - needed
[cylinder] cupboard space.
4) Vaillant VCW combi - abused life of 17 years (lack of maintainance,
zero primary pressure etc.) - multiple faults.
5) Vaillant VCW about 12 years old - good order - spaced needed for
new
kitchen - new boiler to outside cupboard.
6) Glow Worm back boiler - thermostat failure leading to safety notice
by fire brigade! - say 20 years old.
7) Ideal Concord - working order - say 25-30 years old - inefficiency.
8) Glow Worm back boiler - inefficiency - about 20 years old.
9) Glow Worm Space Saver - primary circuit corrosion (pumping over)
about 15 years old- HE failure.
10) Potterton Profile - serious primary circuit corrosion about 10
years
old - HE failure.
11) Vaillant VCW combi - 17 years old, PCB failure - customer chose
replacement rather than a repair.
12) Ideal Condord - thermostat failure leading - about 25 years.
13) Thorn Apollo - 15 years? - neede cylinder space and HW pressure.
14) Alde thermal storage combi - (7 kW boiler and heat bank in a
box) -
poor HW performace and not enough stored energy. - 10 years old.
Looks like a good few of the CI monsters would go on and on until
their
thermostats would fail provided their primary circuits did not eat
them
first!
In the nominal 20 year life of the boiler it is likely to burn 2-5
times
the cost in gas of its total installed cost
In your list the failed boilers, not those that were not suitable for
the
current usage, would have lasted a lot longer if the system was
installed
correctly and/or maintenance was carried out at regular intervals. Even
so
there were many 20 year olders despite the abuse.
A well designed system with a condensing spiral tubed heat exchanger,
top
mounted burner, with the air intake in clear air rather than in a
position
to drag in excessive dust, will last a hell of a long time. The
condensate
washes down the heat exchanger cleaning it. A modern boiler that
analyses
combustion would last even longer as if the boiler was out of tune it
would
lock out.
You mention correct installation and maintenance.
What are the classic installation errors ?
Undersized pipes. Filing loop left permanently connected topping up the
system with fresh water constantly. Over-pressurised system. Under
pressurised system. Having rad valves on all rads and no pressure
differential valve fitted, which means no flow through the heat exchanger.
Some boilers now have these as standard inside the white box. Mains water
pressure too high with no pressure reducer fitted. No anti-scale devices
fitted in hard water areas such as phosphor canisters, or electronic
devices. Some boilers have anti-scale incorporated. Because of the poor
installations some makes have incorporated functions to eliminate/reduce
poor fitting and promote longevity. These are the models to DIY.
And as to maintenance - I've watched what gas fitters do - you're lucky if
you get
more than a quick clean and a gas analyser shoved in. What is the
important
maintenance ?
Keeping the system pressure up for one. If it is down, why is it down?
Setting up the gas pressures and the analyser too.
Incidentally, you talk of reliablility, one of the electronics engineers
here ended up modifying the board
in his boiler because the b*stard blew up every year and cost him over 100
quid to get fixed - cant
recall the make........
geoff will tell you about boards on boilers. There are 100s of them. Some
good, some bad.
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