On Sun, 22 Jun 2008 13:26:19 +0100, "George \(dicegeorge\)"
wrote:

why ae you using copper pipe?
why not black plastic pipe?

Indeed. There are several YouTube videos that do exactly this.

I'd put a lot on my roof
except the weight of the water
micht collapse the roof

It doesn't *have* to be the roof (mine is too steeply pitched anyway).
A slanted south-facing collector-cum-frame in the garden is more than
adequate. Just a garden hose left on the lawn for a few hours in the
hot sun produces incredibly hot water, though not enough of it. That's
the reason for the tank. The thermo-syphon principle will keep
circulating the water throughout the late morning and early afternoon.
Hot water should be available after only a few hours.

MM