Hot water stinks like sulfur

[natp]

We had a new water heater installed and now the hot water stinks like rotten eggs. The people who installed it have not been helpful.

I think the same thing happened when the house was built. Back then, the anode was removed from the water heater and the stink went away.

Questions:

- Does the smell come from bacteria or some inorganic chemical reaction?

- Instead of removing the anode, can it be replaced with something made from a different metal that still protects the heater from corrosion but doesn't make the water stink?

- Typically, how long is the anode? (Can a new anode be installed without disconnecting the pipes running to the water heater so it can be tipped sideways?)

- Money is tight. Is removing or replacing the anode a DIY project?

The well was serviced a few months ago. The water was tested and found to contain bacteria. I put chlorine in the well and tested it again: no bacteria now. The water heater is fed from the water softener.

[Nate Nagel]

here's one link

nate

[Jdog]

I had the same problem. It started about a year after the tanks was installed. I called the 800 number on the tank. They sold me a new anode rod that was made out of a material. Depending on the kinds of minerals in the water, or different parts of the country your in, they recommend different kinds of anode rods. I replaced it. it was tough getting the old one out. You definitely need the right tools, large socket with plenty of leverage. I used a 4' pipe on the end of my socket wrench. The rod was about 3' long. And the pipes didn't need to be disconnected. On he top of the tank there was a plastic pug I took off and then had to clear out the foam insulation (about 3") to find the anode rod. Its been about 2 years now and I haven't had a problem.

[TimR]

Before you blame the anode rod, check for an easier to solve problem.

I've run into the sulfur problem several times at work, and they've always blamed the hot water.

But it's never actually been the hot water, in the cases I've seen.

There is a kind of iron fixing bacteria that can grow, usually in a drain, that produces the smell.

When you run the hot water into the sink, and then into the drain, the smell comes up. You think it's the hot water, but it might not be. (Run some hot water into a glass, take it outside, smell it later.)

At any rate, in the cases I personally investigated, pouring a cup of bleach down the drain slowly took care of the problem. Every time so far.

I don't know how an anode rod could cause the problem. That doesn't make sense to me.

[Ed Pawlowski]

Chemical reaction to the chemicals in the water. Read the article at the link that was posted and you'll understand. The bleach down the drain gets rid of the residue odor that started in the water heater and now resides in the trap.

[TimR]

Well, that's crap.

The problem is the anerobic (iron fixing) bacteria.

They don't care about the anode.

And they CAN live in the hot water heater, if the temperature is low enough, but in my experience (1500 apartments) they are quite a bit more common in the drain.

It has NOTHING to do with chemical reactions.

[Ed Pawlowski]

Sorry, I did not know you knew more about this than the engineers at the water heater companies.

This is better than my explanation.

Cause of Rotten Egg Odor The most common cause of smelly water is anaerobic bacteria that exist in some water and react with the magnesium and aluminum sacrificial anodes that come with most water heaters to produce hydrogen sulfide gas, making the classic rotten egg odor. The problem is most common in well systems, either private or municipal.

[TimR]

I probably don't. But I know more about this than the salesperson who wrote the advertisement you posted. Then again, this is more a question for a biologist than an engineer.

No, it isn't better. Your explanation is fine. I just think it's wrong. .

Agree.

and react with the magnesium and aluminum sacrificial anodes that

No. That's a speculation without evidence or basis in theory. Bacteria produce the odor with or without anodes. The odor is more prevalent in hot water because - doh - hot water releases more of the smell. The anode connection is urban legend.

to produce hydrogen sulfide gas, making the

Gas in tiny amounts, dissolved in water. You won't see any bubbles.

The problem is most common in well systems, either

Yes, including my inlaws's cottage. And in every well system where I've seen this, it has been present in the cold water too. I haven't seen the drain problem in the well systems. But in municipal systems, the bacteria in the drain has been by far the most common cause, and by far the easiest and cheapest to treat.

[TimR]

I did a bit of googling, thinking maybe I could find the species names of the bacteria.

There is surprisingly little on the net, this may require a library.

But I noticed that a large number of promotional web sites, usually selling some kind of treatment for sulfur smelling water, seemed to contain the same words, as if they all quote the same article without citing it. (or quoting each other!)

I could be wrong, but I think they all are using the same 1989 article. Here are the authors: Linda Wagenet is an extension associate and Ann Lemley is an associate professor in the Department of Textiles and Apparel, New York State College of Human Ecology, Cornell University, Ithaca, NY This article talks mostly about bacteria, but it does mention the anode rod possibility. No references for this are given. They may have just passed on somebody's speculation and it has been repeated all these years.

[clare]

The iron fixing bacteria are involved in a chemical reaction, and in many cases it is OBVIOUSLY in the water, because filling a sink with the drain plug in stinks to high heaven.Changing from Magnesium to zinc alloy often solves the problem.

[TimR]

Write the equation then. I don't believe it.

and in

Oh, certainly. The bacteria can live in the well, in the pipe system anywhere, in water softeners, and very commonly in the hot water heater. They're a little hard to kill, because they can be coated with a slime. But chlorine bleach usually does the trick.

But I have seen a number of cases where they lived ONLY in the drain, and pouring bleach down the drain cured the problem.

because filling a sink with

.Changing from Magnesium to

All the web sites say that. At least, all the web sites trying to sell you new anode rods do. Since they also recommend you drain the tank and chlorinate it when you change the anode, I'd guess it probably works, at least temporarily. Funny how "often" isn't always, if the anode is really involved.

I personally have never seen a single case where just changing the anode made any difference and suspect you haven't either.

[clare]

Actually, I have. More than one. And as I've said to several others on the group, just because you have not seen or experienced it does not make it any less true or valid. I've also run across quite a few situations where ONLY the hot water smelled, where chlorine was tried (and was reasonable effective on the short term), and where simply turning up the temperature of the heater to above the now-mandated maximum also solved ( or very substantually reduced) the problem.

[DD_BobK]

=A0of =A0Textiles

Seems like you're expecting research paper(s) on the causes & remedies for sulfur smell in water systems.

IME

Research is typically only funded where there are health & safety or economic issues involved. From my experience and also from my reading on the web, it seems that there are sufficient solutions in existence to the "smelly water problem". Whether the various causes are completely understood does not seem like a high priority for the water treatment community.

Try this, this or this..... must work

btw in the engineering school where I worked for nearly 20 years, water quality issues were studied by civil engineering profs (including those caused by bacteria). Engineers are involved in all manner of research & problem solving.

so your comment.......

[Ed Pawlowski]

Write the equation then. I don't believe it.

and in

Oh, certainly. The bacteria can live in the well, in the pipe system anywhere, in water softeners, and very commonly in the hot water heater. They're a little hard to kill, because they can be coated with a slime. But chlorine bleach usually does the trick.

But I have seen a number of cases where they lived ONLY in the drain, and pouring bleach down the drain cured the problem.

****************************************************

I suspect the stink in the drain starts out in the water heater and just gets worse as water sits in the trap.

I just had the maintenance guy pull the anode on the water heater in the ladies room. First, he drained the tank and the water stunk.

Next, he pulled the rod and it is coated with white stuff that stinks too. It is a combination of a sludge and sandy feeling minerals. The rod is aluminum, but it will be replaced by zinc or magnesium.

From the McMaster catalog: Also known as sacrificial anodes, these rods and pads are attacked and consumed by any corrosive action that would otherwise attack and consume your valuable equipment. Rods have a reinforcing steel core that holds the zinc or magnesium in place until it's completely consumed. They come with NPT hex brass plugs. Connections are NPT male. Zinc rods protect from corrosion and scaling in hot water applications. Ideal for use in salt water. They can also be used in cold water. Magnesium rods protect from heavy corrosion in cold and hot fresh water applications.

[TimR]

Yup, bacteria living in the water. No surprise.

Yup, these bacteria like the sludge, it protects them somewhat from the disinfectant in the water supply, if any. (Assuming a municipal system using either chlorine or the more common chloramine; a well might not have any.)

The four sources you cited above all repeat (without any background) the claim that magnesium anodes cause the problem, and aluminum is the answer. You've just proven them wrong. They also show an ignorance of basic corrosion chemistry.

Did your anode look consumed, or just coated and scaled up?

One of the most obvious ways to shock chlorinate a water heater is to pull the anode rod and pour in bleach. There are other places to get it in, three that I can think of offhand, but all take a little more thought and/or disassembly. I suspect that the way the anode myth got started is from DIYers pulling the anode rod to add chlorine, and the story got confused over the years.

[Ed Pawlowski]

? "TimR" wrote

Scaled up and black. It is about 3 years old. Temperature is about 120. It gets little use most of the week, but one day a week it gets water running through it for about an hour.

[Earl]

You have burning matches in your water.

[John Simpson]

Are there tiny bubbles in a glass of water? If so, do a Google search on sulpher bacteria. I had that problem with the bacteria (well water) in the cold water tank (Adirondack mountains in NY). Chlorine injection would temporarily solve the problem, but eventually I replaced the tank, which solved the problem permanently.

JAS

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