A few months ago I was given 4 solar heating panels by the father of a
friend. He built them in the late 70's to a CAT (Centre for Alternative
Technology) design, basically:

* 1m^2 collector made of sheet copper to which about 10m of 15mm pipe is
soldered.
* Collector backed with aluminium foil
* 3/4" plywood box, insulated with Fibre Glass
* A glass window on the front

Pix he
www.hernibles.com/solar1.jpg
www.hernibles.com/solar2.jpg
www.hernibles.com/solar3.jpg

On a sunny day we reckoned each panel could deliver about 1kW. They were
used for hot water for 25 years (obviously backed up by conventional
heating). I want to refurbish them with a view to getting another 10 years
use.

Q1. The boxes are basically in good shape. The plywood has in places been
damp but is not delaminated. What is the best outdoor treatment for this?
My inclination is to good ol' creosote (I have a secret stash) unless
anybody has a better suggestion.

Q2 I need to repaint the collectors with the blackest matt black paint I
can find. Any ideas? Is there paint made specially for such purposes?

Q3. I do not want a glass window for safety reasons (though I suppose it
could be toughened glass). I imagine some kind of acrylic or polycarbonate
sheet would be sensible. any comments?

BTW the aluminium foil in the original design will be replaced with
horticultural mylar film. The water circuit will be autonomous and
pressurised, feeding a separate "loop" in an as yet unpurchased "heatbank"
type thermal store.

Off to watch the Ice Hockey now....

David.