[JRTJH]

If your trailer has a Suburban water heater that is "gas only" you can not install a electric heating element in the place of the anode rod. Doing so will eliminate the "anode protection" and corrode the steel tank lining causing tank corrosion and premature destruction.

If your trailer has an Atwood water heater that is "gas only" you can remove the plastic drain plug and install an electric heating element. The Atwood tank is an "aluminum alloy" that does not require an anode rod as the tank functions as its own anode.

Keep in mind that the electric option does not provide as much hot water as the gas option, so taking a shower with the electric only function is typically not acceptable for most owners. Many of us use both the gas and electric option and for both Suburban and Atwood water heaters, the "recovery rate" is determined using "maximum heating capacity" which means that the 6 gallon Suburban water heater "recovery rate" of 17 gallons per hour is determined by using both gas and electric heating systems. Using gas only is around 11 GPH and using electric only is around 8 GPH.

I'd suggest you consider the significant reduction in performance associated with the electric "hot rod" style water heater add on modification. You'll probably find it unacceptable performance for most functions requiring hot water except for limited hot water use. YMMV