"Nightjar "cpb"@" "insertmysurnamehere wrote in message
...
AL_z wrote:
My last c/h boiler was a combi, and it broke down about once a year, on
average. Conversely, my parents had an old regular-type boiler (i.e., not
a combi) which never needed any maintenance in about 30 years. I now want
to
install a c/h system in my new house. So, regarding my choice of boiler:
Considering the cost of purchasing, plus the cost of maintenance balanced
out against the difference in thermal efficiency, might I be doing myself
a favour by installing a cheap, old, reliable, standard boiler, say from
a demolition yard, rather than forking out for a modern condensing combi?

Reliability is more about make than type, although a system (regular-type)
boiler is less complex than a combination boiler.

Not much at all. A combi is system boiler with a 3-way valve and a plate
heat exchanger for DHW. 90% is the same.

The other advantage of a system boiler is that the hot water is stored in
a tank, which can have a backup immersion heater and that gives you belts
and braces cover.

An in-line instant electric heater can be fitted in the combi outlet. A
small box say under the sink.

Both types are available as modern condensing boilers.

My personal preference is for a Vaillant system boiler and mains pressure
hot water tank, both of which are sitting in my side porch awaiting
installation.

A poor choice as the unvented cylinder is a potential bomb. Unvented
cylinders need an annual service costing £60-£100 a year. The best, if you
have the mains pressure and flow is a high flowrate combi. Floor mounted
like the Worcester-Bosch 550 or wall mounted like the ATAG 51kW. The ATAG
is quality. It works out cheaper to fit and install and saves a hell of a
lot of space and no bomb in the house or need annual service expenses.

It is best you send back the boiler and cylinder and reassess.