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hanknjoyce's avatar
hanknjoyce
Explorer
Sep 26, 2017

Atwood Water Heater Rotten Egg Smell

I completely drained and flushed our Atwood water heater recently because I noticed that rotten egg smell. We are now on the road and the smell is back. Never happened before. Did I not flush it well enough? Or should I have put some type of disinfectant in the tank?

In our 47 years of RV-ing I never had this recurring problem.

Hank
2005 Mandalay DP

6 Replies

  • midnightsadie wrote:
    are sure the smell is the heater?? batteries dry smell almost the same.
    If you haven't experienced it, it's not pleasant. The stink comes right out of your faucets, no where near the batteries.
  • Old-Biscuit wrote:
    May need to sanitize using bleach....1/4 cup per 15 gallons.
    And it is fine for the RV plumbing.

    IF stagnant water was left for long period of time then you may need to do a vinegar soak with 4 heat cycles to clean inside of tank.
    4 gallons vinegar/2 gallons water for 6 gallon water heater. Remove Relief Valve, use funnel to pour mixture in, install Relief Valve. Heat vinegar solution thru 4 heat cycles. DON'T use any hot water thru faucets....drain then flush rinse afterwards.
    Sulfur smell will be gone



    This is basically what I did and it works great. I poured 3 gallons of cleaning vinegar (Walmart, like $2.00 a gallon) in it and let it sit overnight, pulled plug and flushed it out. Two seasons later and still no smell. I was amazed at the amount of calcium deposits etc that came out when the Vinegar was changed.
  • May need to sanitize using bleach....1/4 cup per 15 gallons.
    And it is fine for the RV plumbing.

    IF stagnant water was left for long period of time then you may need to do a vinegar soak with 4 heat cycles to clean inside of tank.
    4 gallons vinegar/2 gallons water for 6 gallon water heater. Remove Relief Valve, use funnel to pour mixture in, install Relief Valve. Heat vinegar solution thru 4 heat cycles. DON'T use any hot water thru faucets....drain then flush rinse afterwards.
    Sulfur smell will be gone

    Atwood does NOT use any anode rods so that is NOT the issue......unless someone misguidedly installed one which could be reacting with water especially if magnesium.
    Atwood -NO anode rods
  • It could be sulfur bacteria (not dangerous, only stinky) which you picked up with a load of water (not uncommon with well sources), and which changes sulphates in the water to "rotten egg" gas. Disinfect it. Chlorine bleach is most available/cheapest (put a cup in your tank, pump it into the heater, let it sit overnight), but not particularly good for the rest of the water system. If yours has an anode rod (not all Atwoods do), replace it first - the magnesium in them makes it worse, and used ones have lots of crevices for the bacteria to live in.

    Iodophor is a better alternative but not usually something you can pick up at the local store, unless there's a homebrew beer store around.