On Fri, 24 Jun 2005 23:16:05 +0100, "Doctor Evil"
wrote:


"Andy Hall" wrote in message
.. .
On Fri, 24 Jun 2005 21:20:14 +0100, "Doctor Evil"
wrote:



The Takagi condensing multi-points, not available in the UK (yet) are
"very"
efficient, and can return around 38 litres/min. Instant water heating
has
become the norm in Japan now. It is a case of use low energy and store
lots
of hot water taking up space, or use a lot of energy all at once, suing
most
of the energy available down your gas pipe. They also developed
multi-points that can be installed outside to save space too.

The T-H1 at over 95% efficient and over 30 litres/min flowrate.
http://www.takagi.com/web2003/pdf/TH1.pdf

You really are a sucker for claims on web sites.

No. I know a.lot abouit numbers.

Mmmmm.... I'm not sure whether to say that you are a one, or a
number two really.



- The so-called 95% efficient is measured
on what system? Presumably
a U.S. one?

They do a give a table at the end of the manual.

If you mean the one on pp31, it's a set of data for water flow rates
vs. input and output temperature. Did you mean that page or something
else?



There's an asterisk against
the number and they do not say
what the measurement method
is. The specs seem to miss out on heat
output to water so one can't even see
the story from that.

95% efficioency on a scale to 109%, so you can work it out from that.

Oh come off it, even you know that that doesn't fly. The two
systems in use here (SEDBUK and the continental Europe one) are quite
clearly defined. If it's 95% for a condensing boiler on the 109%
efficiency scale, then the figure is crap for this product. I would
be inclined to believe the number because of the archaic secondary
condensor design. Even you have said that regarding boilers sold here
before.





- If it's the same one as is used in the
UK, then I find it very hard
to believe that it is achieving 95%
when everything here is achieving
90-91%.

You don't have seasonal efficiencies on multi-points, they are rarely on
part load.
90-91 is seasonal effifiencies - SEDBUK.

Of course. That's why I didn't think for one moment that it would be
95% on a SEDBUK type of scale when everything here is 90-91%.


If it's the continental European system then the range is
normally in the 106-109% range, and this would be pretty poor.

- Looking at the internal design, the thing has a secondary heat
exchanger and upfiring burner. Hardly leading edge, is it?

Yes well the construction is not ferrous, In cheapo condensing boilers the
primary heat exchanger is ferrous and the secondary is not.

The design is archaic. This is not the great product that you claim.




- The NG input is 199,000 BTU in deprecated units, or 58kW. This is
virtually the entire output from a domestic supply, leaving no spare
capacity for anything else unless a commercial supply is installed.

Enough for a hob.

Oh please.




- Your claim that it delivers 38lpm is only under the best possible
conditions. This is equivalent to 10 U.S. gallons/min, and from the
graph, this is only achieved for water temperature of 60F (15.5C) in
and 95F (35C) out (hardly hot water is it?) or 70F (21C) in and 105F (
41C) out (tepid). If you look at the rate for a more realistic
figure using the UK defacto standard of dT=35C (8C to 43C) (46F to
109F)then the output is at around 6 US gpm or 23lpm which is not
impressive at all.

You need to look at figures again.

I have. You look again. Remember also that there is a difference
between imperial and U.S. gallons.....

Let's be honest. The product's a piece of junk, isn't it?






--

..andy

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