new to rving, resorting camper

If you don't have a battery bank and never camp without the generator or shore power. Then no you don't. I bet you will need at least one good battery for 12v power. The question is do you have just an inverter or a converter/inverter that also charges the battery?
Bill

The Rv trailers are all built to run on both 12VDC and 120VAC to satisfy every one's style of camping...

This is what a typical 30A Trailer wiring configuration looks like. As you can see there is alot of 12V DC built into a typical RV Trailer setup..

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I don't think I would ever completely take away the DC operational status...

If you are still planning to tow your RV down the public roads you will still need to satisfy the DOT requirement of having an active battery setup to operate your trailer Electric Brakes in the event your trailer becomes disconnected from your truck while being towed over public roads. This is an enforceable State DOT Safety requirement...

I guess not having 12VDC circuits would mean your RV trailer would become a TRAILER PARK trailer haha...

Maybe never on the road but setup permanently somewhere and never be towed anywhere???

Roy Ken

Restoring, not resorting.

There are a few systems that are specifically 12 volt. Water pump, furnace fan, etc. Yes you could eliminate the 12 volt circuits, get a 12 volt converter similar to what folks used to use to power a cb radio or car stereo in their homes, but purchasing and installing it will largely consume any savings you may be envisioning.

Moved from Forum Technical Support

Usually the lights and vent fans are all 12V in a travel trailer, besides the things others have listed (water pump, various appliances you're likely replacing, the radio if there is one....)

Rewiring the lights for 120V would be a rather tricky process unless you have the walls and ceiling apart already. The existing 12V wiring would not be acceptable for 120V use.

lights etc are already electric
12v electric, the built in converter, should probably be replaced with a new one
if you means residential 120v fridge, many of us have done that, electric heat might get expensive, depending on where you are at, and a propane furnace is always a good back up option, a heat pump instead of the roof top A/C
will give a/c or heat down to about 40 degrees, below that you will need the furnance or other form of heat
and electric cook top or MW is easy to use
I suggest, if your going ALL electric for major appliances and heat
that you get an electrician to install a 50amp RV service, instead of the orginal 30amp service
there is no need and its a lot of trouble, to rewire all the lighting to 120vac
just replace the lights with some 12v LED fixtures and continue to use 12v

with a modern converter 120v to 12vdc, (Not Inverter) different device , you don't have to have a battery,
but IF there is a shore power failure, No lights, No water pump, No furnace, unless you have a battery

an INVERTER uses battery power to create 120vac power for things like the TV, when there is NO shore power or generator
like late at night in a campground with no hookups
or during a power failure
how long you have power depends on how many batteries you have and how much power you are using, you can watch tv for a number of hours, but electric heat or A/C is almost impossible on battery power
so a propane heater or furnace is a pretty god idea for 'Most' people

Those old TTs had only 120 and propane (including a lamp above the table in front), no 12v. Did have electric brakes. But now you need a breakaway system for the brakes so a 12v battery is compulsory. How to keep it charged up? A converter.

With the battery and converter, now you can add 12v things the original never had.

OK you have all given me a lot to think about and change thanks.

If it was me, I'd make it all 12 volt.
If you don't want to mess w/ or maintain a battery, you don't have to. To operate on shore power, all you will need is a new converter, which does not need a battery,......or even use a battery charger of adequate amperage to operate the 12v items you choose.
If you need to leagalize the breakaway for towing, you can use a 12v lantern battery, as many do on non powered trailers.