Hi doug,
My back yard testing was done at about 22 C and encompassed 24 hours of non use. It is pretty much "in the ball park". The extrapolation to propane use may be suspect.
doughere wrote:
You WILL save by turning the heater off. pianotuna estimate of waste is probably a little too high, you could use that as your benchmark worst case. Is it worth your effort or not, or do you have need for water at high temp more often than not. I changed the fixed 140 degF thermostat to an adjustable set to 120; this saves a little and prevents scalding. We keep heater off when not needed; saves a little more.
Doug