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Compact combis |
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| message from Ellen Mizzell on 13 May 2004 |
I'm trying to find a combi that will fit in the very small kitchen of
the very small flat I'm considering buying.
The space on the only external wall in the kitchen is very tight --
about 18-20 inches. Is there a compact combi that would fit?
Alternatively - is it possible to put the combi on an internal wall, and
run the flue to the external wall? What would be the likely limitations
in terms of distance from the external wall?
At the moment the flat has a cylinder in an airing cupboard and
something called a Thorne Apollo boiler on the kitchen wall. This flat
is so small, it would really help if I could get rid of the cylinder.
Much thanks for any advice.
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| Lobster replied to Ellen Mizzell on 14 May 2004 |
I've just bought an Ideal Classic combi, which will fit in a space 18.75"
wide according to its specs
Regards
David
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| John replied to Lobster on 14 May 2004 |
The Classic Combi has been discontinued but keeps on being resurrected for
housing associations and other big users but is generally considered to be
old technology these days. Its narrow but VERY high by comparison with other
units.
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| Ellen Mizzell replied to Lobster on 14 May 2004 |
Noted, thanks. I guess I'll probably try for a 400mm one as being the
smallest. (And hoping that's not asking for trouble....)
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| Hugh replied to Ellen Mizzell on 13 May 2004 |
http://www.electroheatplc.co.uk/
instead of a gas-fired boiler.
and they are only 90mm square!
Hugh
"Ellen Mizzell" <news@127.0.0.1> wrote in message
news:MPG.1b0db9d191b1c1c989685@news.ntlworld.com...
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| Ellen Mizzell replied to Hugh on 14 May 2004 |
Thanks, interesting idea but I notice on the website that the price
comparison relies on the Economy 7 tariff. I think I'd rather stick to
gas. But thanks for mentioning it.
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| Pete C replied to Hugh on 14 May 2004 |
Hi,
They would cost about 4x as much as gas to run though.
cheers,
Pete.
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| Toby replied to Ellen Mizzell on 13 May 2004 |
Most are around 400mm wide (that's 16").
It may be salient to consider the route a gas pipe may need to take when
positioning the combi, it will most likely need to be 22mm diameter from the
meter, but you may find the smallest combi can manage with a 15mm gas supply
pipe.
You should be able to fit the boiler to a side wall and run the flue to the
external wall. Many will come with 1m of 100mm diameter flue pipe & a 90deg
connector for the boiler. This may often be positioned so the pipe can exit
to either side or the rear. 1m extension pieces are also available, up to a
total length of around ~4m.
Before going to far check the rules regarding clearances between boiler
flues and other features such as windows, gutters, other flues etc. as these
will determine where the flue can exit.
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| Ellen Mizzell replied to IMM on 14 May 2004 |
Thanks, I'll check that one out too. I must admit I'd prefer Worcester
Bosch to Ariston. I've got an Ariston at the moment -- can't remember
the make. It's been nothing but trouble. Of course that's not to say
the MicroGenius would be similar but it has rather put me off the name
of Ariston.
Will do. Thanks.
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| Ellen Mizzell replied to BillV on 14 May 2004 |
Thanks -- noted for the short list.
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| Ellen Mizzell replied to Toby on 14 May 2004 |
Thanks, that's just what I needed to know. I'm hopeful that a 400mm one
will fit on the external wall, where the small Apollo boiler is at
present. That will be the simplest. If not, from what you say I'll
still be able to put it on the side wall. I'll take your advice and get
all the clearances checked before I proceed. But it sounds as if it
should be ok.
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| John Rumm replied to Toby on 14 May 2004 |
Not sure about most...
I had the same problem looking for a narrow combi and found lots that
were bang on the spec I wanted except for the width (many of the combis
are 450mm wide alas) - went for the Ideal ISAR at just under 400mm wide
in the end.
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| Ellen Mizzell replied to John Rumm on 14 May 2004 |
Thanks for mentioning that. I just looked it up. It's a condensing
boiler? Don't they have a reputation for troubles? Or is it just that
they're more expensive that makes them less popular? I'd be prepared to
pay the extra for a condensing boiler, in the interests of efficiency,
if it will fit and won't give me headaches.
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| IMM replied to Ellen Mizzell on 14 May 2004 |
The older British ones did. The newer batch are fine.
The cost is made back quite quickly in reduced gas bills. And as fuel will
rise in price quite sharply, the payback may be very quick indeed.
They are much the same as any other boiler. From April all boilers will
have to be condensing boilers.
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| Ellen Mizzell replied to IMM on 14 May 2004 |
Thanks. It's definitely on my list.
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| BillV replied to IMM on 15 May 2004 |
I'd heard somewhere that this regulation is coming in.
Is that April 2005?
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| IMM replied to BillV on 15 May 2004 |
Yep. All bar an earthquake it will be introduced. I have spoken to a few
boiler manufacturers about the nuisance plume, which will create problems in
flats. Two said they have a way of getting around that, but no info at all.
Could be BS.
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| Ellen Mizzell replied to IMM on 15 May 2004 |
What is the nuisance plume?
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| Andy Hall replied to Ellen Mizzell on 15 May 2004 |
It's a plume of visible water vapour that may come from the flue under
some conditions of operation of a condensing boiler.
The amount of the plume will depend on how hard the boiler is working,
the temperature and the design of the boiler. Some boilers generate
more than others, and in general, the newer designs emit rather less,
being able to collect more inside to be delivered to the drain.
Whether it is a nuisance or not depends on the smount, circumstances,
location of flue and your point of view.
My own boiler has very little pluming and is certainly not a
nuisance.
.andy
To email, substitute .nospam with .gl
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| Ellen Mizzell replied to Andy Hall on 15 May 2004 |
Sorry for a stupid question but would this plume occur outside, i.e.
after the flue exits from the flat, or does it occur at the interface
between the boiler and the flue?
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| Andy Hall replied to Ellen Mizzell on 15 May 2004 |
No it's not stupid.
The plume, where it happens, would appear from the flue exit outside.
With a non-condensing boiler, the temperature of the heat exchanger is
arranged to be at a high temperature (70-80 degrees Celsius). The
combustion products, which are basically water and carbon dioxide plus
a few other things at much lower concentrations, exit from the flue at
a fairly high temperature, and unless the air outside is very cold,
are invisible. You may have noticed visible water vapour from the
flues of conventional boilers on very cold days.
A condensing boiler is more efficient partly because it has a larger
and better heat exchanger, but also because it is designed so that it
can operate at lower temperatures. At a temperature of below 54
degrees, water, which has been in the form of steam condenses to water
or water vapour. This change of state (or phase as described in
physics), releases what is known as latent heat. This heat is
"free" and is added to that produced by the burning of the gas, thus
improving boiler efficiency. THe mechanism is similar to that used
in a fridge or the reverse of sweating - you feel cooler with sweating
because heat is required to evaporate water.
Depending on the boiler design and temperature of operation, more or
less of the water vapour is collected inside the boiler and is
delivered to a drain. Any that is left as visible water vapour is
delivered out of the flue into the air along with the flue gases.
There may be some amount of water deposited from the vapour to the
inside of the flue and so it is normal to arrange that this is sloped
back towards the boiler slightly so that any water runs into the
boiler's drain arrangement and does not drip from the flue exit.
The water is slightly acidic and would mark brick and stonework.
The condensing boiler has a drain arrangement which is normally done
with small plastic pipe like overflow pipe to a suitable drain inside
or outside the house.
Air for the boiler is drawn in from outside via the flue, which is
normally a concentric tube arrangement, so there is nothing to and
from the inside of the house.
.andy
To email, substitute .nospam with .gl
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| IMM replied to Andy Hall on 16 May 2004 |
It is not free. You have paid for it in your oil and gas bills.
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| Andy Hall replied to IMM on 16 May 2004 |
That is why I put the comment in inverted commas.
(I know that you have difficulty with spelling and punctuation, of
course)
The energy is obtained as a result of the change of state of the water
from gaseous to liquid phase as it cools. It is energy that is not
directly derived from the burning of the natural gas and heat transfer
to the heat exchanger, and is as a result of the latent heat
phenomenon. In that sense it is "free" energy that you would not
otherwise have and is in addition to what is measured by the simple
examination of energy input vs. energy output.
Latent heat is also exploited for air conditioning and heat pumps,
where the heat delivered to and from a space is greater than the
energy input required to do so.
In the case of air conditioning the latent heat of condensation and
evaporation is used to transport the heat energy. In the case of a
condensing boiler, the latent heat is added to the heat resulting from
combustion at the heat exchanger.
When I went to school, latent heat was a first form grammar school
physics experiment. Perhaps you missed class that day.....
.andy
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| IMM replied to Andy Hall on 16 May 2004 |
You should have written what I did instead.
< snip tripe by Andy >
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| Andy Hall replied to IMM on 16 May 2004 |
I rather thought that it would be too difficult for you to comprehend.
Presumably you don't know how your time machine works either...
.andy
To email, substitute .nospam with .gl
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| IMM replied to Andy Hall on 16 May 2004 |
< snip tripe by Andy >
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| Ellen Mizzell replied to Andy Hall on 15 May 2004 |
That's crystal clear. Yes, I've seen vapour from the flue but wasn't
sure if this was something different. I don't see the vapour as a
problem myself but I guess I'll check with the freeholders to be on the
safe side.
Thanks very much for the explanation.
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| John Rumm replied to Ellen Mizzell on 14 May 2004 |
Yes it is a high efficiency condensing combi. The "reputation for
troubles" is a bit of an old wives tale... many years ago when the UK
makers first started making condensing boilers some of them were poor
(partly because they were adopting / reusing parts and materials from
existing designs that were not appropriate for consensing boilers). The
current crop of condecing boilers however should be fine.
Yes they will cost more to buy, although you will recoup that and more
in the life of the boiler in reduced fuel bills. So unless yo were
planning to move in the near future it would be a false econmy to buy a
less efficent boiler just because it is cheaper.
As the building regs evolve to require ever more efficent boilers, the
non condensing boilers will soon be forced off the market anyway.
You can get a duff example of any boiler I suppose - but if you stick to
respected brands it should be no more likely to cause a headache!
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| Ellen Mizzell replied to John Rumm on 14 May 2004 |
Would it were so. As mentioned elsewhere, the Ariston I've got now has
been a real pain in the neck.
I'll certainly consider the ISAR. Thanks.
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