RV Repair Manual
for the RV Do-It-Yourselfer
There are several options to help your factory water heater improve heating recovery time. One common low-cost modification is installing an aftermarket RV water heater Hot Rod conversion kit, which inserts an electric heating element into the tank via the drain plug port. This element uses ~425 watts of 120V AC power to assist the propane burner during heavy demand. While helpful for extending recovery time, it does not provide an endless hot water supply, and replacing the sacrificial anode rod requires extra attention to tank corrosion prevention.
Tankless water heaters heat water on demand rather than storing 6 to 10 gallons of heated water in a heavy steel tank. When a hot water faucet is opened, an internal flow sensor detects water movement, automatically igniting the burner or energizing the heating element to heat water instantly as it passes through the copper heat exchanger. Closing the faucet immediately shuts off the burner.
While point-of-use electric tankless shower heads exist, they require heavy 120V AC current (20+ amps) on a dedicated breaker circuit. For off-grid boondocking and standard RV electrical systems, propane-powered units are far superior.
A propane-fired RV tankless water heater delivers 40,000 to 60,000 BTU/hr of heating capacity, drawing negligible 12V DC power (1–2 amps) to run the electronic ignition control board and forced-draft exhaust blower.
The most seamless way to go tankless is installing a direct-fit drop-in RV tankless replacement heater designed to fit standard 6-gallon or 10-gallon water heater wall cutouts. Modern retrofits include door conversion flanges and digital thermostat wall controllers to adjust water temperature inside the bathroom.
Installation Tip: When removing your old tank unit, turn off the LP gas supply, disconnect the 120V AC circuit, drain the tank using an anode socket wrench, and disconnect PEX water lines. Ensure the exterior sidewall flange is thoroughly sealed with butyl tape and non-sag silicone sealant during final assembly.