In message , "Nightjar
\"cpb\"@" writes
Doctor Drivel wrote:
"Nightjar "cpb"@" "insertmysurnamehere wrote in message
om...
Doctor Drivel wrote:

"Nightjar "cpb"@" "insertmysurnamehere wrote in message
news:lvOdnRoPVvdcWELWnZ2dnUVZ7vqdnZ2d@giganews .com...
...
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.

That is still more complex than a system boiler.
Not much.

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.

They are fairly useless if you want to fill a bath though.
It is for backup and will do a shower.

I don't have a shower or a shower attachment.

If you want full backup have two boilers and one being electric and
a backup genny as well. Where do you want to stop?

An immersion heater in the hot water tank will do me. I said backup,
not paranoia.


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.

Worse than a couple of air receivers working at 11 bar?
Uh?

It would seem to be a simple enough question. Is an unvented cylinder
at mains pressure a greater danger than two similarly sized air
receivers working at 11 bar? I've had those around for over 20 years
without being worried about them blowing up.


Unvented cylinders need an annual service costing £60-£100 a year.

Wow, a whole pound or two a week.
That is £100 in 10 years. £2000 in 20 years.

Compound interest on planet drivel

--
geoff