-> Right now in the afternoons the water too much too hot to touch.
I'm glad I'm not the only one getting scalded by his solar water heater.
Too DANG hot!
I took a page out of your notebook and put a 40 gallon heater tank on
the roof, painted whatever color black the factory paints them.  It
still has an element in it for emergencies, but we're finding that it
takes a LOT of cold water turned into the shower to temper what's coming
from the heater as solar heated.  (My wife says God's thermostat is set
too high...)  Haven't measured the temp yet, but it's HOT and stayes so
well past bath time for the lady which is after the ten o-clock news.
Crude as our system presently is we're quite pleased with the results so
far.
 ^..^
--- FidoPCB v1.5 beta-'j'
---------------