Thanks for a great reply, I'm now a follower.
I have the same on demand water heater as in your picture, just never hooked it up. I'm going to get a propane fired, on demand heater some day but who knows when?
When the heater in your photo shorts out, you do get shocked but has never happened to me, just people I know.
If I'm a little chilled ( very rare ) I'll put a pot on the stove and mix it in a 5 gallon pail to wash with. In the mountain towns here the water is cold, But where I live is almost warm in the afternoon. so not an issue.
Looking forward to reading your blog now, Thanks for dropping by mine :-)

Cheers