Philip5malin wrote:

In my community in Davis, Calif, many residents had solar water
heaters built in when the homes were built 30 years ago. Many of them
disappeared now. I still have mine, but is shut off. First things
many people found is rust in piping, rust on pipe joints, calcium
deposit on heating systems etc, making leaks. It is not fun when it
starts leaking on pipe joints on roof. Second, is roof anchors, many
anchor positions starts to lift up as times goes by, sun heat
expansion, wind lifting anchors etc. Making leaks on roof when rains.
Then many homeowner fed up with it, when they replace the roof, the
roofer does not know how to handle the system, or not want to liable
with it, saying they are not plumber, and they will simply get rid of
the system.

I'm in Phoenix, and many solar heaters have disappeared here, too, but
not because their collectors wore out (tempered glass, extruded
aluminum, and copper tubing last forever) or lifted off the roofs but
because pumbers wanted too much to repair them and wanted to install
$900 solar tanks instead of modify regular electric heaters for solar
use.

I've gotten 6 free solar collectors from homeowners who abandoned
their solar heaters.