Water heater on demand, or ??

We did our first full hook-up trip, just to try out all of the systems. I turned on the water heater and after a while checked and had hot water, then just left the switch on. It was a warm evening and we had our windows open and in the middle of the night the water heater burner ignited and was so loud it woke me up (I didn't know what it was until snooping around in the dark.) I flipped off the switch and went back to bed.

I tend to leave mine on a lot.  Charlie is right about the thermostat though.  I don't know what temp it's set at, but the water heater is going to keep it at that temp.  Unless it's really hot out it's going to fire up from time to time for short periods to maintain that temp.  (There are no places on this planet where it gets that hot outside.)

It's a small water heater so it heats up fast, and doesn't take a lot of energy to maintain.  That argues for both turning it off between uses and leaving it on.  I turn mine off some times, when I think about it, but I don't worry about it.

TT