Sounds like the OP has a water heater powered by both electric and gas in his new to him TT. If you need hot water really fast, then turn both on, but usually you just let it run on electric - if your at a site with electricity - your already paying for the electricity so just use electric only. Make sure you fill it up the tank first by connecting to a water source and turning it on.
Since you have a disconnect switch, then just use that when storing, but uif your storing at a storage facility, then remove the battery so it won't grow legs and walk off. Take it out anyway and buy a battery tender or smart charger - put it on your bench and let it it maintain it's charge.
If you plug in your TT and the converter keeps charging the battery, you may cook it if your not careful.
