CharlesinGA
Well-known member
Edit: rereading your post, I see you are referring to a home water heater. Even my house one is well insulated and I do not think it cycles on very often while just sitting.As far as wasting water, a conventional water heater comes on even when no water is being used when the tank temp drops, like during the night.
You are assuming that people leave their (RV) water heaters on all the time. I switch my Atwood on about 15 minutes before I plan to get in the shower and by then the water is warm enough to use only the hot water side for the shower. When it gets full hot, I shut it off and it stays hot all night. I have indicator light switches to remind me the heater is on, so I don't forget to switch it off.
Charles