In article , Malcolm
Reeves wrote:
The SEDBUK figures really confuse the issue because of the
factors used. For the purposes of looking at boiler behaviour
it is much more useful to use the measuring methods used in the
rest of Europe. These specify certain temperatures and firing
rates.

If the figures are available. The only database I know of with
all the uk boiler. If you have a URL for another database
please post it.

I would guess that what Andy is referring to the fact that the
SEDBUK efficiencies are derived from formulae which can be found in
the [free] SAP-2001 book Appendix D. For an on/off boiler this is
0.5(Efull+EPart)-2.5, for a modulating boiler 0.5(Efull+EPart)-2.0,
less 4% if the boiler has a pilot light - other formulae apply to
combis of various types. Efull and Epart are the efficiencies at
full and 30% load.

Using 50/50 part and full load figures is reckoned to give a fairly
accurate measure of likely efficiency under UK climatic conditions.
It would be quite possible that some other EU country uses a
different mix and if you were comparing two boilers with
significantly different part and full load performance their
relative assumed in-use efficiencies would be different to that
shown by SEDBUK.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
Free SEDBUK boiler database browser
http://www.sda.co.uk/qsedbuk.htm