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Well, of course MY passive HW design solves all those problems, and freezing and overheating too- at least on paper LOL!"
Well done! I poured over quite a few passive hot water designs for a system here, but the climate is different. During winter here, temps go down into the minus 30s Fahrenheit, and wind gusts, to about 110 mph. So an active system was needed (
this, with some modifications).
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It does remove the little-discussed risk of legionnaire and other disease from stagnant ‘warm’ water too."
That's very important. Very well done! Yes, storage temperatures must be kept a little more than high enough to kill the bugs, and periodical sanitizing is a good supplement to maintenance (once per year water test, change and sanitize working in my area and climate).
Yeah, I remember seeing that in my researches (very good site)... and thinking “Oh no! There’s got to be a better way!” LOL!
But for that kind of system it struck me as a very good design.
Can you quantify it’s performance and payback?
Or are you just satisfied that it makes a significant improvement in cost and comfort.