Hot Water Heater Test

Replacement what?
To test the water heater it must be filled with water or yo run tye risk of burning it up.

Only way to fill water heater with water is to fill rv plumbing system with water.

Course you could.........close cold water inlet (and hot outlet if you have one) then remove PRV and with a funnel pour water into WH tank. Then re-install PRV after you have filled it and fire it up.

You can fire up gas side without water in tank......valve in propane, light off stove top burners to get propane flowing and then turn on WH on 'gas'. Listen for it to 'click' (spark) and then listen form main flame. After you hear main flame light off and stay lit then turn it off. Won't be enough heat generated to do any harm.

Then later on when you have water in system you can test electric heat side of WH. At least you'll know that gas side works.

Rv antifreeze about $3 gallon
Just check the whole water system at the same time and rewinterize it only takes a gallon and 10 minutes .
The water heaters are not made by the camper cos but by third parties.
Open the outside access door and look for the brand or post a pic here and we ll help you find one if need be.
Installed yourself complete sys about $300.

OK , thank you guys , it's a Suburban and I got the gas to light it just took a little while.
The switch next to the Suburban gas on/off switch isn't labeled well and only says tank heater it must be the electric element. I could take the elec. element out see how it looks and test the contacts with a meter. Thanks , D

No need to test the hot water heater...if it's already hot it's working! You might be concerned about the regular water heater though....