Originally Posted by norwood12800
To my knowledge, all the electric hot water hearers in at least the newer GT models can left on as long as there is water in them. That being said, if the tank is empty (you have drained it) you must turn off the tank or you will ruin it. Additionally, when stored even with water in the tank, it should be turned off to conserve battery life.
The electric heater portion of the Suburban hot water heater is totally independent of the DC/propane portion. The only commonality is the water in the tank.
The electric element being left on (outside black switch) and has no effect on battery life because that circuit does not use battery power at all. (see attached wiring diagrams.
If the propane is turned off and the gas switch is left on, the water heater will attempt to light 3 times, then shut down. The board will remain powered and in this case, if the battery is left connected, it will deplete the battery slightly faster that normal since the other parasite loads (propane detector, clock, etc) will be depleting it anyway.
If you have no water in the tank, NEVER have either system turned on since damage to the water heater will occur; just to different systems.
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