On Fri, 18 Jun 2004 09:30:25 +0100, "IMM" wrote:


Stored hot water - so water (hot and cold)
available if mains supply fails

-This is so rare an event that is it is not worth taking into
consideration.

It happens to me every few months......

Stop making things up.

Would you like to see the copies of letters to and from the water
supplier? Email me your address and I will be pleased to send you
copies.


-Cylinders may need replacing every 8 to 10 years in hard water areas.

One can use a water softener or phosphate
doser to avoid this.

Water softener at approx £400 just to buy then the cost of salt too and they
take up space. A de-scaler will only delay the inevitable.

Rubbish. The cost of the water softener can easily be offset
against the cost of cylinder replacements. When I replaced mine a
couple of years ago after 20 years, the inside was still pristine.

The cost of salt is more than offset by the savings in detergents and
shampoos. I have posted full details of this previously.


-Very poor shower pressure, having to use an expensive and noisy power
shower pump in some situations.

Flow from a combi can also be poor if it is not a large one.

You size accordingly. Many conventional boilers will not fully heat a house
and leave the occupants cold in winter. So, when you fit one you size to
suit. You don't undersize. The same with combi's.

The issue is the lack of the storage element as you well know,



-The cylinder takes up space.

So does a combi if of high capacity
and fitted with some form of
storage.

Such strange logic. A conventional system takes up two lost of space and a
cylinder takes up lots of space unless you go square like an Elson. You
obviously can't figure this out.

It is a question of location as well as of size.



-Ugly zone valves and pumps around cylinder.

One can have a system boiler.....

You still need a 3-way vale or TWO 2-way valves.

So what.


-No wating for cylinder to reheat

This is irrelevant if the cylinder is adequately sized.

You mean oversized, taking up space and more standing heat losses.

This discussion has also been done to death before. The incremental
space is negligible as is any additional heat loss with a properly
insulated cylinder. I presented calculated numbers on these on
previous occasions.


-High pressure shower after shower can be taken.

That depends on the water supply
and temperature and rating of the
combi.

You size to suit. Duh...

One still cannot get a quart from a pint pot....



-Have a high output, so house warms up faster.

Than what? A system boiler can be equally effective.

Combi boiler by their nature have outputs.

Get away.

Conventional boilers are sized
only for a particular house requirements. A combi in 90% of cases will have
spare heating capacity.

You know full well that that comment is utter crap. System boilers
are widely available with large ranges of modulation.



-All the system is inside the one white box.

A system boiler can achieve that as
well, with the exception of the
cylinder.

...and the cylinder takes up lots of space and has standing heat losses and
a 3-way va;lve has to be installed as well.

Cylinders do not take up any more space than the equivalent storage
capacity built into a combi or CPSU.

This is of course unless you have perfected the technology to compress
liquid phase water.



-No pipes to freeze in the loft

Irrelevant if they are properly insulated.

Which is more expense.

This is rubbish too. The cost is negligible as you often point out
when proposing ridiculously large amounts of loft insulation.




Cons
slower bath filling

High flowrate combi's are available, so not true.

We've had that debate and there are demonstrable limitations.

Stop babbling balls..."High flowrate combi's are available".

This depends upon your definition of "high flow rate". I would not
consider 22lpm at 40 degrees to be high flow rate.



No warm airing cupboard

A small rad can be installed in the airing cupboard taking up no space.

A post suggesting that there are no
disadvantages to combis should be
regarded as suspect. Nothing is ever as clear cut.

You know nothing of combi's to come out with a ridiculous statement.

So you're saying that there are no disadvantages at all? You really
have been drinking the Koolade, haven't you......


..andy

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