Left empty H2O Heater on while empty

rowekmr wrote:
As the title says I dewinterized the TT and forgot (rushed) left the hot water heater on thinking it will take time to warm the water. Water still wasn't hot after 30 min so left it on gas mode then wasn't able to get back for a few days.

I figured I still had the bypass on when it was still cold so I turned the heater off and waited awhile to fill it with water but didn't turn it back on yet. Do you think I cause any damage? It was one electric heat for awhile then gas heat for a few days. Do they have safety cut off just for this reason?

Yes, there are high limit thermostats on RV water heaters. I would inspect carefully if there are any leaks at fittings or valves. If you can operate a hot water side valve (sink?) and the water continues to flow, you can see if the tank is full and if leaks are present.

Your electric element, if so equipped, won't work for long without submersion. The propane burner should light and function well. Inspect it when you first fire it up.

Good luck with the heater.