Most dont sanitize water heater?

That was gnarly man.

The sulphur smell is caused by a non-toxic, sulfate reducing ( i.e. sulfur digesting) bacteria called Divibrio Sulfurcans. It flourishes when the right combination of conditions exist in your RV water system. These conditions are elevated sulfur levels, high levels of activated hydrogen, and low levels of dissolved oxygen. Sulfur is present in all water although usually in low levels. Occasionally, because RV water systems receive water from many sources, sulfur levels are encountered that are high enough to support odor causing levels of Divibrio Sulfurcans. Most of the the activated hydrogen necessary for Divibrio Sulfurcans growth is present as a by-product of the cathodic reaction within the hot water tank. The highest levels of activated hydrogen occur on the surface of the anode rod. That will be the first place that the bacteria will colonize. Oxygen impedes the bacteria growth, but the lowest levels of oxygen are found in the hot water tank, as hot water has a lower level of dissolved oxygen than cooler water.

There will almost always be some Divibrio Sulfurcans found on your anode and this is perfectly normal. Usually routine tank flushes will prevent bacteria levels that are high enough to cause odor problems. However, my experience is that when once the bacteria film thickens and sloughs off in to the system and sulfur odors are detected, nothing short of draining and flushing the hot water tank, cleaning the anode, and performing a standard chlorine flush of your entire water system will solve the odor problem.

The reason that the Divibrio Sulfurcans are rarely found in your home hot water tank is because colonies will not grow in water that is hotter than 138F. Home heaters are consistently above this temperature, but RV systems often fall below this. Although the temp must be lower than 138F to start growth, temps above 138F will not kill the colony once it's been established. A lessor factor that keeps this bacteria from growing in your home tank is the fact that the home tank has a higher turnover rate and hence the oxygen levels are higher.

As I stated, the Divibrio Sulphercans bacteria is non-toxic. Most of the time it's growth is restricted to a light film on the surface of the anode rod and is not a problem. Presence of the bacteria indicates that the cathodic reaction is taking place, or more precisely, presence of the bacteria on the anode rod indicates that the cathodic reaction is taking place on the anode rod. The cathodic reaction is always taking place but is controlled by directing this process to the rod. If the rod is missing or has been significantly dissolved, the cathodic process begins to occur on the inner surface of the tank and the bacteria begin to colonize over the entire inner surface of the tank. It's then that the problems associated with Divibrio Sulphercans are exacerbated.

One last thing: the lower the level of oxygen, the less sulfur needed to be present to provide the necessary conditions for this bacteria growth. Typically the older the water in your RV system, the lower the level of dissolved oxygen. So the low-sulfur water source that usually won't provide the conditions to allow the bacteria to significantly grow may support growth as the dissolved oxygen levels fall over a period of time.

The proper method of dealing with this issue is to chlorinate your water system.

TurnThePage wrote:
Maybe we should just agree to disagree. I tried bleach. It didn't work.

I'm in agreement with that. :B

Possibly your bleach solution wasn't strong enough.

Maybe we should just agree to disagree. I tried bleach. It didn't work.

Not true.
I have eliminated the sulfur smell in my water heater with bleach.

Boon Docker wrote:
You go ahead and use vinegar, the rest of us will use what works. Sodium hypochlorite. :B

I treat my tanks just like everybody else. But the sulfur smell from the water heater is a different animal. If you ever encounter it, feel free to fill the heater with bleach. It won't work.

You go ahead and use vinegar, the rest of us will use what works. Sodium hypochlorite. :B

Bumpyroad wrote:

TechWriter wrote:

TurnThePage wrote:
It takes lots of vinegar and time to kill whatever it is that lurks in the water heaters. Bleach doesn't do it. There's plenty of articles about it out there in google land.

How about a couple of links to those articles?

bleach works great.
bumpy

Not true. I tried it. And I provide links above.

TechWriter wrote:

TurnThePage wrote:
It takes lots of vinegar and time to kill whatever it is that lurks in the water heaters. Bleach doesn't do it. There's plenty of articles about it out there in google land.

How about a couple of links to those articles?

bleach works great.
bumpy

If I leave water in my water heater too long I can get a rotten eggs smell from it. A flush and a fresh anode fix the problem. Now when I'm going to be home for a while I empty the hot water tank and let the AZ heat and dryness take care of any bacteria.