"Ed Sirett" wrote in message
news
On Sat, 27 Mar 2004 15:42:49 +0000, John Stumbles wrote:

"Ed Sirett" wrote in message
news
On Tue, 23 Mar 2004 19:05:28 +0000, Skyloop wrote:

I'm a novice with a choice to make between a Vaillant Turbomax 824e
or a
Worcester Bosch 28i Junior combi (running 9 rads), and I'm wondering
whether
anyone has any comments on the Vaillant's 'Aquacomfort' feature which
seems
to provide 'instant' hot water.

Is it the kind of feature which should influence my decision?

Sincere thanks for any advice, it's tough learning about these things
from
zero!

This feature has been around most middle market+ combis for a
long while. All it means is that the innards are kept hot on standby in
readiness for HW production. The feature is user selectable.

IME this means the boiler fires perhaps a couple of times an hour for
about 30 seconds each time.

A reasonable make like the W-B might well also have this feature.

I'm pretty sure the Junior won't do this - it's the type with some sort
of
combined primary heat exchanger for CH and DHW rather than a secondary
for
DHW. (Very nice build and simple inside: just a flow sensor switch in
the
cold inlet, no diverter valve etc. I've just hung one but not fired it
up
yet so we'll see how it flies .....)

What sort of price did you pay?

About 550 inc std flue from Jayhards (now Bathroom Centre or something like
that)

I presume it's around 24kW with a SEDBUK of 80%.

yup (leastways the 24i is :-)


The design sounds a bit like a Ferroli.

never seen one of those in the flesh, but there are some pics at
http://homepage.ntlworld.com/john.stumbles/Junior/

You can't see clearly from the photos (and I couldn't see clearly in the
flesh) how the CH and DHW parts of the heat exchanger are arranged: whether
alternate finned tubes serve CH and DHW, or whether -- and I'm guessing
from the necessity to prevent either boiling when the other's being
heated -- that it's some sort of concentric pipe arangement to keep the CH
and DHW in intimate contact.