Strong Sulfur Smell in Hot Water

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MrJim

Senior Member
Joined
Jan 23, 2015
Messages
206
Location
USA
Vessel Name
Irish Miss
Vessel Make
Mainship 30 Pilot Rum Runner Classic
Our boat has a small hot water heater. When we use it and draw some hot water from it, the water gives off a strong sulfur smell. It's so bad, our hands stink of sulfur after we wash and dry them. Can anyone recommend an effective way to get rid of that odor? It's not in the water tank -- the cold water doesn't have that smell. It only happens when we use the hot water.
 
Your smell from the hot water heater is due to the mag./alum anode on the heating element and its reaction with anerobic bact. This happens after the water heater has been sitting for awhile without use. The anode is doing its job and is slowly diminishing. The most effective solution to this problem is to shut off the unit, then shut off the intake valve, drain a few gallons out at a faucet then if possible inject some Hydrogen-Peroxide into the unit (maybe by way of the pop-off valve). Then open the water inlet fill then allow a small amount (1/2 gallon to 1 gal.) to drain out through the faucet again. Let sit for a few hours. This will correct it until you leave it unused for a period of time again.
 
As Ulysses said above, you need to kill he bacteria. Bleach or peroxide will work. Also if you can replace the magnesium anode with aluminum it will react less.

David
 
David: you are correct that bleach will work too. I had suggest the Hydrogen peroxide only because it usually comes with some alkaline stabilizers that raise the ph to a level that is not as corrosive as sodium Hypochlorite (bleach). Typically people will put in way too much bleach and its not good for the metals in the heater. 1 teaspoon would probably be plenty of bleach.

dan
 
Greetings,
Mr. u. Might I ask how much you would suggest for a 60 gal gas fired HWH with an aluminum anode? We're experiencing the same SO2 phenomenon in our dirt house. I always thought it was the iron fixing bacteria that produce SO2 as waste that produced the smell. Sorry for the thread drift folks.
 
This happens after the water heater has been sitting for awhile without use.

Exactly. I suspect the boat sat unused for a long time before I bought it, so I guess that would explain it. Thanks for the input. Do you think putting a dose of hydrogen peroxide in the fresh water tank and running it through the heater would also work? (We don't drink it, just use it for washing) The fresh water tank is pretty small -- around 20 gallons or so if I remember correctly -- and the hot water heater is much smaller.
 
We had a similar problem and I found that if I filter the dock water as I fill the tank using a charcoal filter, the smell went away. I don't know what the chemistry is that's involved, but it worked very reliably. You might give it a try. I just bought a household filter canister and off-the-shelf filters from any plumbing supply house. Cheap and easy.
 
Sulfur smell in Florida water is a norm, unless you aireate it, enjoy the free mineral water. At the Fountain of Youth in St Augustine it would cost you for a drink of it.
 
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RTF: 2 oz of Hydrogen Peroxide should easily treat 60 gallons IF it is only associated with the hot water side of the plumbing as the original post indicated. Iron and Manganese do produce a very similar taste and odor problem in household plumbing which is often more pronounced in the hot water side. If it is an Iron and/or Manganese problem it will show up as black or red very, very small particulate matter in the bottom of your toilet tank (not bowl), The iron and manganese will precipitate out of the water when passing through air, almost immediately, as your toilet tank's inlet water gap allows this to happen. You may also see it in ice cubes and in your washing machine. Iron and manganese occur naturally with the decomp. of leaves and such in drinking water reservoirs. During the spring and fall it becomes problematic for many municipal water systems. All lakes and ponds will go through a spring and fall "overturn" when the water temps in all layers of the lake reach the same temp. and the wind will actually bring the bottom water full of decaying matter and its byproducts (Iron and Manganese) to the surface.
Probably too much information. If you find it in your toilet tanks call your water supplier and ask if they have had problems and or complaints about it in the past. It is considered a "taste and odor" problem and is not necessarily a health risk. If that is the case at your dirt house let me know. There is only about one way to remove it. It will not "filter" out in that it is water soluable until air hits it. Like sugar water you can filter it forever but it will still be sweet.

dan
 
Mr. Jim: It may clear up once you start using it regularly. But yes, a small amount of chlorine or Hydrogen Peroxide in the fresh water tank should do the trick. Contact time is of importance. Let the stuff run through the hot water system then turn off for 12 hrs and let it sit before flushing out.
dan
 
Filter the water. We have good water supplies where I live yet I filter the water. Over many years enough sediment has accumulated in the tank to be a problem. Now I'm dealing with the buildup, slow as it was.
I started filtering several years ago and the water is much better now than before I started.
As a mtce. dose I add ~ 1 teaspoon full of bleach to each 50 gal. tank when I refill . Not even enough for my wife to taste, and darn it she has good taste buds, but at that level of dosing it keeps the water from foul tasting and smelling without causing the bleach taste.

When I was getting that suphurous odour it sometimes took two separate shots of bleach at about two tablespoons of bleach per 50 g tank and then about one to two weeks later I had to do it again. At that point my wife rebelled as the bleach was noticeable. To me OK but not to her.

After and with the filtering, the inital treatments and the ongoing periodic mtce. treatment we have had no more trouble.

And yes, if the H.W. tank has an anode change it.
 
Greetings,
Mr. u. Might I ask how much you would suggest for a 60 gal gas fired HWH with an aluminum anode? We're experiencing the same SO2 phenomenon in our dirt house. I always thought it was the iron fixing bacteria that produce SO2 as waste that produced the smell. Sorry for the thread drift folks.

RT...actually the iron oxidizing bacteria create a micro-environment that promotes the propagation of 'sulphur' producing bacteria. Both can cause odors. My previous home used a well as it's water supply; the well water was very high in Iron content and eventually became very 'infected' with Iron oxidizing bacteria and subsequently suphide producing bacteria. This manifested as 'rust' stains in sinks/faucets and iron oxide 'stalactites' on the yard irrigation nozzles in addition to the funky rotten egg smell. I had to treat the well bore with a gallon of bleach at least every year. The bleach, in addition to disinfecting the well/plumbing, caused soluble iron to precipitate as insoluble iron oxides that plugged up all the screens at the aerator tips of the faucets and black particles (that U referred to) in the tubs. I had to unscrew the aerator heads on all the faucets before treatment and flush all the fixtures for about an hour after treatment. This sediment also had to be flushed from the hot water heaters every year. Come to think of it now...that house must have thought it was a boat with all that annual maintenance:blush:. I have never used H2O2 but I would suspect, since it is an oxidizer, it would also produce precipitable iron oxides.
 
Rardoin: Well put (no pun intended). You are correct that both chlorine and H202 are oxidizers and will promote precipitation of the soluble iron and manganese. You may want to google up "greensand filters" if it is a major problem at your location.
 
Rardoin: Well put (no pun intended). You are correct that both chlorine and H202 are oxidizers and will promote precipitation of the soluble iron and manganese. You may want to google up "greensand filters" if it is a major problem at your location.

Not a major problem any more....got rid of the house and the wife:eek:. ;)
 
rardoin: Yes, that would certainly be a fix. It might be more expensive than the greensand filter though. I have done one of those myself.
 
They say you get what you pay for......based on that I've got quite a lot from that adventure:rolleyes:.
 
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