[Myrddin]

I put a solar hot water panel system on my house in San Diego in 1986. System had a 20 year warranty. The installing company and panel supplier were out of business 18 months later. The panels lasted 6 years before the insulated holding tank on the roof failed due to high mineral content in San Diego tap water. The cheap freeze plugs crapped out the 2nd year. I had to spent $85 each for good quality brass units to replace the crappy PVC. My side yard got pretty wet as the failed units dripped hot water off the edge of the roof.

As a system, it provided 100% hot water from March 1st to Nov 1st each year. I had to go to "pre-heat" mode Nov 1st to Feb 28th where the warm water from the roof is boosted to preferred temperature by the natural gas water heater.

The natural gas prices never reached a level that would have paid back the investment vs staying with the old natural gas only water heater.

I removed the inoperative system from the roof when replacing the roof. The tank went to the dump at my expense. The quartz heating panels were picked up by a local solar contractor who still had a few other victims of the same vendor who had a potential need in the future.

[Sherman Logan]

I have considerable experience dealing with the results of “active” solar house heating. The panels and connections spring leaks and water damage the house. Not to mention freezing and bursting.

Not good.

Anything with hundreds or thousands of plumbing connections in your home is not a good idea.