On Wed, 09 Sep 2009 21:22:22 +0100, The Natural Philosopher wrote:

Like other posters my boiler rarely runs over the summer, and the solar
system acts as a pre-heat on the HW cylinder over the winter, reducing the
gas used then a little.


Like other posters, my boiler rarely runs over the summer.

And I have no solar panels at all!

Same here. My boiler has been on 4 times since late April and then only to
spin the pump.
Gas cost=0.
--
Peter.
The head of a pin will hold more angels if
it's been flattened with an angel-grinder.