"Christian McArdle" wrote in message
...
Also, consider the Worcester Bosch Greenstar with additional diverter
valve
(assuming they still make it in the new range). This allows separate
temperature settings for DHW and CH.

I tried to get info from W-B on this and I'm sure they said you can't
have
two temps.

Ah. So the new range doesn't have this option? That's a real shame. I
would
have thought that more boiler manufacturers would be making such products
due to the recent shift in requirements. Central heating systems (both
rads
and underfloor) are now designed for much lower temperatures than
previously
both for operational and efficiency reasons. Hot water systems, now often
heatbanks or fitted with TMVs, are often designed for higher temperatures
to
improve capacity, performance and biological safety. Just the provision of
a
terminal allowing for 2 set temps would be enough.

Christian.

The W-B techies on he phone wasn't that clued up I may add, and appeared to
be speaking from crib sheet. So you might be right.

I fully agree. It is a simple thing to incorporate into a modern boiler.
Even Ravenheat have this facility.

But a Danfoss BEM 5000 waether compensator does offer this facility with a
stand alone third party product and will enhance efficient condensing
operation by lowering the flow temp to the conditions. And you only need a
cheapish boiler too. I always did it with a basic weather compensator using
a relay switching out the compensators burner signal

Most condensing boiler will be less efficient heating DHW rather than CH,
although ACV HeatMaster condenses when heating DHW, because of the way the
tank in tank thermal store is configured.