I first posted this on the UKHA forums but it was suggested to post here for additional views.

Our current boiler is starting to play up, I keep having to reset it
as it fails to run when required. I know it is a particuliarly bad
model as it has been on Watchdog, Potterton Suprima. In addition it
is non-condensing and the Energy Saving Trust state efficiency of
~75%.

So I am likely to replace it in the next few years, but this posses
some questions:

- Should I go the whole hog and change to an unvented system (what
are the benefits?)

- In the future I plan to install solar panels for hot-water and
also a wood pellet stove for the front room with a small back-
boiler. Therefore, the gas boiler will then become secodary heating
source just providing top-up to the renewable heating supplies. But
I need a system that can cope with this more complex setup.

- Any recommendations on manufacturer? I am thinking Viessmann as
they seem to have a good approach, German engineering and have good
controls and integrated with their own solar system. But I have also
been recommended Worcester Bosch and Baxi.

Any thoughts, comments would be appreciated.

Paul