On Thu, 29 Nov 2007 16:06:41 +0100, John wrote:

(Andrew Gabriel) wrote in
:

In article ,


at the moment the boiler thermostat is set to 65 deg and
the cylinder
to 58 deg.

my question is it better to set up to boiler thermostat to
max ? will
the boiler still work in condensing mode ?

The boiler would be running at its most efficient when the return
water
temp to the boiler is 54c

It still gets even more efficient at lower temperatures than
that.
My condensing boiler runs at 40C return temperature for
heating,

True but I was replying to OP and making some assumptions based on his
plumbers comments
I.e. I would be surprised if radiators have been replaced and resized to
allow such a low return temp. And I think it's only the ecomax combi
that has a separate HW temp setting.


I believe AG may have done that for himself. I doubt that serviceable
radiators are worth replacing with oversized units on fuel efficiency
grounds. But with a new system you would try to design/guesstimate for
cooler return temps.

Many many combis have seperate controls for heating and the MAXIMUM HW
temp, even really low end units.

There are only a few quite high end models for non combis which have
different setting for HW mode and heating mode, and then only in the
larger units.



--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
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