We are currently looking at updating our central heating and DHW. The
existing system is old and looks like it has been cobbled together at
various points in the past - for this reason and to facilitate other
house work, we are planning on putting the new boiler and DHW tank in
the loft.

Following research on google we have decided that an indirect Pandora
heatbank best fits our DHW needs (mains pressure is sufficient and the
ongoing safer operation vs a traditional unvented cylinder appeals to
SWMBO).

Apologies if the following appears to ramble - I am not an expert and
profess only to have gained my knowledge from this exceelent group and
many of the learned regular posters...

Not fully DIY but for reasons of speed and time we will be employing a
plumber to do the installing (I am however doing the
design/specifying). As seems to be the norm he was very reluctant when
I first mentioned the Heatbank to him and he was steering me towards an
unvented cylinder ...after running through the spec with him
(downloaded from DPS) in words of 1 syllable he has now come round to
the idea - probably as he can see the pre-plumbing of various parts
makes his life easier...!

The Pandora I have initially specified is 180l / 100kw / inlcuding two
2 port valves (S plan) that would serve heating/DHW.

Now the main issue - choosing an appropriate boiler to cater for the
heatbank and also serve the heating (radiator) system. Following
various discussions with my plumber we have calculated our heating
requirements at around 26kw and to err on the side of caution we are
looking at boilers between 28-31kw.

Following a number of positive posts and reserach into the features
offered by the Man Micromat (outside weather compensation/analogue
temperature DHW sensing/fully modulating pump etc etc) I have looked
into the Man Micromat H or HS series. I like the idea of these
features and also the ability (AIUI) to have a different set
temperature for DHW and a separate temperature for the heating.

Following considerable discussion with Eco Hometec they have raised a
number of issues that are bascially steeering me away from choosing the
Man:

1) The Man DHW probe can only sense temperatures upto 65deg - the
heatbank is suited to be heated to 75/80deg therefore not really
suitable. The Pandora has its own sensor(s) however these do not
directly feed into the boiler. Maybe this isn't a problem?

2) Due to the wiring of the Pandora (?) only one fixed temperature
output from the boiler will be provided therefore the separate setting
of temperatures for DHW/heating is not possible?

3) Due to number 2) the fully modulating room sensor and outside
weather compensator would not be required?

I am slightly confused as all of the literature I have read suggested
the ability to run separate temperatures for heating/DHW and now it
seems as though this isn't possible and therefore all of the additional
features the boiler is capable of are also not relevant? Unfortunately
am not expert enough in all this to argue the toss greatly so was
hoping for some additional input from the group?

a) Does the Pandora negate the need to have a "complex" boiler like the
Man?

b) Would a Pandora without zone valves etc team up with Man and its own
diverter etc?

Perhaps I should just be looking at a simpler 28-31kw boiler to avoid
any unecessary complications?

Many thanks to all replies in advance
Robin