"Mark" wrote in message
...

FFS how many showers do you people have a day.
Has anyone given the slightest thought to how efficient this will be, and
the likely rise in temperature achievable.
Even I cant be bothered to build one of these.

Another know-it-all. Do a Google on groups and type in gfx. If you did
that first you wouldn't nake such an idiot of yourself. There are some
Americans who have these installed and reported figures on them. The average
temp rise is 17C. In effect it makes your cylinder bigger too. When
showering they are effective because you are heating the incoming cold water
with waste water simultaneously.

Domestic applications have a far loger payback than commercial. Heavy use
of waste water would make it feasible, in places sucj as hotels. Make your
own, as in solar panels, and the payback is quite quick. See my post on
making one.