Jim K wrote:

nice hot day.

Since the interesting discussions on solar PV, am now pondering DIY
solar water heating possibilities, anyone care to share? or links,
pointers, suppliers (good/bad/cheap/expensive) all (constructive)
suggestions welcomed..

trawled on here first and been reading about Solartwin (seems ££££?)
and Navitron DIY kits - any experiences? other suppliers? other ideas?

I spent some of last week commissioning our solar heating installation.

The thermal store is a Heatbank from DPS who have now gone bust but the
defunct company was taken over by a larger company (I forget which one)
and they now trade as Thermal Integration Limited - www.heatweb.com.

I can't fault the product, it's excellent. We have a 300 litre Xcel unit
that provides points for underfloor heating, radiators, and a heat
exchanger for mains pressure hot water. Inputs are taken from an LPG
boiler, solar panels and a wood burner in the kitchen.

At the moment the solar panels and wood burner are not connected. The
LPG boiler is connected and is functioning well. This week the unit is
operating on a low setting as we bring the underfloor heating up to
temperature. All seems fine and installation was a doddle because the
thermal store has the pump and mixer for the UFH and there's no need for
the UFH heating manifold to have either of those - saves on cost.

Although the install looks hideously complicated it's a doddle. The
thermal store is vented so no sealed system worries.

The solar panels are vacuum tube units bought from a business called LC
Solar, but they are clearly re-badged Chinese units and were forgettably
cheap. These will be connected to a Resol controller and the only
headache at the moment is working out what to do with excess heat. In
the long run this will go to the swimming pool in the short term I
suspect that a black painted radiator on a north facing wall will have
to do.

I wouldn't touch Solartwin with yours, it's a cack, cheapskate design
and it's hideously expensive. For the cost of one of their units I
bought a Heatbank, two solar panels, two log burners an LPG boiler and a
2500 litre underground LPG tank, paid for an LPG certified plumber to
connect the boiler and still had cash left over for the installation of
drainage.