Does your RV water heater even have an anode rod?
This is the first thing to know, because it depends on your tank. Suburban water heaters use a steel tank and a sacrificial anode rod — a magnesium or aluminum rod that corrodes on purpose so the tank doesn't. Atwood and Dometic (formerly Atwood) heaters use an aluminum tank with no anode rod; they have a plastic drain plug instead.
Putting an anode rod in an Atwood/Dometic aluminum tank isn't necessary and can cause problems. Check which tank you have before you buy parts.
When should you replace the anode rod?
On a Suburban (steel) tank, pull the anode rod once a year and look at it. When it's about 75% consumed — thin, lumpy, or down to the wire core — replace it. A rod that's completely gone means the tank itself has started taking the corrosion, which shortens its life.
Step-by-step: flush and replace
- Turn the water heater OFF (both gas and electric) and let it cool completely — the water inside is scalding.
- Turn off the water supply and relieve pressure by opening a hot tap inside, then open the heater's pressure-relief valve.
- Remove the anode rod or drain plug with a 1-1/16" socket and let the tank drain fully.
- Flush the tank: run a hose or a curved tank-rinser wand into the opening and blast out the sediment and crud until it runs clear.
- Inspect the anode rod; install a new one (or clean and reuse the plug) with fresh PTFE/thread tape.
- Close the relief valve, refill the tank (leave a hot tap open until water runs steady to purge air), then restore power and check for leaks.
Why does my hot water smell like rotten eggs?
That sulfur smell is a reaction between a magnesium anode rod and bacteria in the water. Flushing the tank and switching to an aluminum anode rod usually clears it; a sanitizing rinse of the fresh water system helps too. Don't ignore a constantly rumbling or popping tank either — that's sediment boiling, and a flush is overdue.
Stuck on this one? Put Major in your pocket.
Tell RV Journey Genie your make, model, and symptom and get a step-by-step fix — by text, voice, or photo — before you ever call the shop.
Frequently asked questions
How often should I replace my RV water heater anode rod?
On a Suburban (steel-tank) water heater, check the anode rod once a year and replace it when it's roughly 75% consumed. Atwood/Dometic aluminum tanks don't use an anode rod at all — they have a drain plug.
Does my RV water heater have an anode rod?
Only if it's a Suburban steel-tank heater. Atwood and Dometic heaters use an aluminum tank with a plastic drain plug and no anode rod. Check the brand before buying parts.
Why does my RV hot water smell like rotten eggs?
It's a reaction between the magnesium anode rod and bacteria in the water. Flush the tank, sanitize the fresh water system, and switch to an aluminum anode rod to clear the smell.
What size socket fits an RV anode rod?
A 1-1/16-inch socket fits the standard RV water heater anode rod and drain plug. Make sure the heater is off, cooled, and depressurized before removing it.