In (rec.radio.amateur.homebrew), Anthony Matonak wrote:

In the 80's there were a lot of government rebate programs to promote
the use of solar water heaters. This gave rise to many installers who
existed simply to exploit the rebates and as a result they installed
shoddy equipment and gave buyers unrealistic expectations. Once the
government rebates dried up these predatory companies disappeared
and their warranties along with them. This is why there was such a glut
of broken down solar water heaters and people completely dissatisfied
with the entire idea. This doesn't mean that they can't be cost
effective. I've seen many solar water heaters that have been in
continuous use for 20+ years with only minimal maintenance and the
owners of these appear to be satisfied.

In fact, we had one of these installed around 1980, just after the
Feds started the rebate program and my late wife's dad died, leaving
her a bunch'o'bucks. It worked _very_ well indeed until June 2002,
when it died catastrophically, leaking water in a proprietary fitting,
just after we got back from Canada. It gave yeoman service up to then,
and if I could find someone with the parts, I'd put it back in service
again. It was _really_ nice to have 300 gallons of hot water _and_
forced-air heating to all the rooms in the house. Now we're back to a
floor furnace.

The only thing I had to do in all those 20+ years was install a switch
to sense loss of water pressure and turn off the recirc pump for the
silicone oil, so that it wouldn't overheat and decompose because it
didn't see cool water in the heat exchanger. After a little bit of cut
and try, the plumber and I got that working just fine.

Oh, and we did actually wear out (water flow around a bend in a tube
finally wore through the tube wall) a heat exchanger, but that was
replaced under warranty.

I miss it.

--
Mike Andrews

Tired old sysadmin