Water Heater Rescue: Know-How, Solutions, Parts graphic

Tanklets > Water Heater Odor

Other Topics :

Horrific Smell

Q: Recently drained the water from the house to add an outdoor spigot in our yard. Now after the water was turned back on the hot water faucets are smelling so foul. What is troubling to me is that this was not a problem before.

Although I don't think the house was ever drained in the past, this being the first time, now the hot water is disgusting. It's so terrible I can't wash dishes, bath me or my children, and being that it is winter washing in cold water just will not cut it for me and bathing my kids in this water makes this very urgent in my eyes. It smells so bad, I don't want to introduce the smell into the dishwasher or the washing machine so those appliances have not been used.

We tried to drain off just the water heater and it seemed to make the problem even worse. If I need to buy something to fix it so be it, but it was not a problem before and now it is...and I know this has to do with us draining off the house water to install this outdoor spigot. Anyone ever have a problem similar to this?

A: Could you describe the odor? What does it smell like? Does it smell at all fixtures? Do you have well water? Do you use a water softener? -- Randy

Q1: My mother in law says it smells like rotten cabbage. I think it smells just rancid. Worse than a sulfur smell and more like a raw sewage smell...poop...ick. We work off a well and do not use a water softener. And it is coming from all fixtures.

A1: The only thing that comes to mind is dirt got into the line where it was cut to add the spigot; the dirt had bacteria in it which are now VERY happy in the water heater. I'm guessing to fit the scenario. If so, the thing to do is probably to chlorinate the water heater. This means adding at least 1/2 gallon of bleach to the tank and letting it sit overnight. Then drain and flush. Fill drain and flush again to be sure all the chlorine is gone. Run treated water to the taps also, so the lines can be filled and "detoxed." -- Larry (12/25/11)


Drain Odor Blamed on Water Heater

Q: I'm interested in resolving the smelly water issue. I have tried everything on this list:

*Hydrogen Peroxide
*Bleach Chlorine
*Magnesium Anode Rod
*Aluminum Anode Rod
*Aluminum/Zinc Anode Rod
*Powered Anode Rod
*Water Softener ON & OFF line
*Raised temperature of WH also

And still smell returns within 24 hrs or less! The water heater is an AO Smith ProMax GCV-50 200/201 series. New home purchase in June 2010, municipal water and only get the smell in the showerhead closest to the water heater. No smell in cold water. This water heater has an aluminum hex head anode from factory. The factory states that there is only one anode in this model. I can't confirm this because the heater does not have flex tubing on the hot water nipple. The spec sheet, owner's manual, and service manual only reflect one rod. What do I do? My wife is really after me on this!! Thanks in advance for your help.

A: If you only have odor in one place, that means it is not the water heater. I really regret that you've changed all these anodes. There are other posts in The Tank like this, where it turns out to be bacteria in the sink overflow, or a sewer issue. Tell us more about this situation and we can probably resolve it. -- Randy

Q1: I'm open to suggestions, the shower stall water only smells when someone is taking a shower. As soon as the stall dries up, no smell. I have had my nose close to the drain and haven't smelled anything when shower not in use. Should I do the smell test while taking shower? The shower is used everyday so if there happens to be a p-trap under there, I'm sure it's not dry. Our maid reports the smelly problem when she is cleaning the shower stall glass, walls etc..using hot water. Last night we took a shower and had not noticed the water heater pilot had extinguished, the water temp was not as hot and the WH did not kick in to heat the water obviously, we had no smell. I then turned the WH back on and smell returned.

A1: Please don't spend any money or do anything until Larry Weingarten has a chance to troubleshoot this. He is very, very good at this. If the hot water only smells bad in one place, it can't be the water heater at fault. If it were that, you'd have rotten eggs at every faucet. For that matter, ARE you talking about a rotten egg smell or something else? That could be important.

So often, when people say "My water smells," we tend to assume that it smells like rotten eggs because that's a very common problem. But occasionally it's something else, so we go down a long track without really understanding each other. I'm not happy that I sold you a powered anode that didn't solve a problem. The product is still a good thing to have if you're using a water softener, as it doesn't wear out, but that's not why you bought it. -- Randy

A2: Hello: Reviewing this discussion, the facts seem to be: You get odor only in one shower stall. You've tried everything in the heater thinking it is the source of odor. Odor is affected by running the water. As Randy said, unless the odor is at every hot tap, the problem is not in the heater. This leaves the main suspect which is the drain/sewer/vent system.

There is (or should be) a vent pipe near the shower and this pipe usually goes up and out the roof. There is a newer device called an "air admittance valve" that allows air into the drain system as needed, but it's less likely you have one of these. If you have steel or cast iron drains, it's quite possible the vent pipe has rusted through and is leaking gray water/sewer gas. If there is a crawl space, some lucky person gets to crawl down there and have a good look.

If there is a slab, the only trick that comes to mind is to climb up on the roof and pour some mint oil down the correct vent line, then go inside the shower and see if you can smell any mint. The test for new systems is to plug off the sewer and fill the system with water. It can be a pain to do, but water always leaks where it can. Another inconclusive but easy test is to put plastic down to block the drain and then run water. Any smell? If not, arrows point to the drain lines. Do let us know what you find. -- Larry

Q2: Last night I removed the AL/Zinc rod, poured down Hydro Peroxide and plugged the hole. Water softener is still bypassed. While taking a shower smell was slightly present, but when shutting off water smell was more present. I smelled the shower drain and it had an ugly smell that almost made me vomit. I poured Hydro Peroxide down the shower drain and left for work.

The home was purchased new about 8 months ago and was probably on the market another 8 months. The home is two story with the problem drain in the first floor, the home is on cement slab and there is a vent with an exhaust motor in the restroom. I can't see any other type of vent. Is there a "P" trap in the shower drain? How do I remove the smell, can I shock the drain, does it help at all?

A3: There may not be a good "P" trap in the shower drain as code requires. Venting in drain lines is a different beast than the motorized vent you mention. It is a part of the drain system that usually runs up through the roof to balance air pressures in the drains so water is not pulled from traps. This water is what prevents that foul odor from getting into the house. I might suggest having a plumber with a snake camera come and do a video of the drain line if he can. If it is built improperly, the builder will need to come fix it :? -- Larry

Q3: GOOD NEWS! Got rid of the oder! The drain pipes were probably cleaner than new ones. The smell came from the shower drain. I learned that the shower drain is three pieces. The tile is porous and organic matter traps between the tile floor and the water seal/pan and can't be seen. I resolved it the following way: Removed strainer and taped drain hole with gorilla tape, duct tape also works. I then replaced the strainer to make a better seal and plug the drain hole.

I used a mix of clorox and water and allowed the mix to collect about an inch high and left it overnight. Smell is gone! It was definitely matter between the tile floor and the water pan etc...I then installed the power anode rod and put the water softener back on-line. The family is finally enjoying hot no smell showers. I persued this smell from many different angles for a month until I found the culprit. I want to Thank Randy, Larry and everyone that contributed and shared there thoughts and experiences to help me solve this issue. -- (3/1/11)


Metallic Smell and Powered Anode

Q: After years of suffering with discolored & smelly hot water, I flushed, dosed with hydrogen peroxide and installed a powered anode. Clear and odorless water resulted. After four months in service an occasional shot of particulate could be observed at the beginning of a shower. Upon flushing the tank bottom, slight particulate & essentially no discoloration was observed. At this time (five months in service) a distinct odor has developed which is detectable even when washing hands. Questions: How can it be determined that the powered anode is functioning properly? The green light remains on. Should I expect to dose with hydrogen peroxide on a routine schedule?

A: If the light is on, the powered anode is operational. Something to remember: its primary purpose is to keep the water heater from rusting. Resolving odor problems is a fringe benefit. There has been only one other instance out of more than 400 where odor came back, and I never figured out why. If there were no anode, there might not be any odor. So, I have a couple of questions, and my friend Larry Weingarten may have some later. First, is it only hot water that smells, or does the cold water smell, too? Second, what is your softener set at? Third, what is your thermostat set at? -- Randy

A1: Hello: Only a few questions: Is the odor at every tap? Does it happen only when running hot water or can it happen when running just cold? Does the softener treat the whole house or only the hot? As a test, try bypassing the softener for a few days and see what effect that has on the odor. -- Larry

Q1: Odor is present in hot water system only and is noticeable at all hot water dispensers. Measuring the discharge nearest the heater, the water temp is 138 F. Cold water hardness measurement at mean time between recharge cycles shows 120 ppm. Odor is distinctly different from that experienced over the years. This is a "metallic" smell. Odor is present in hot water distribution only. Softener serves both hot & cold. Will bypass softener as you recommend.

A2: "Metallic smell" makes me wonder what sort of plumbing is in the house. Is it steel? -- Larry

Q2: Bypassing the softener for a few days may have lessened the metallic odor somewhat. The plumbing system is essentially all copper, but I did locate (using a strong magnet) one iron "T" fitting under the pipe insulation. Most importantly, you advised the powered anode to be functional so I will plan to shock the system periodically with hydrogen peroxide. Thanks for your consul. JD PS: Considering well water with iron content, I suspect some of the smell may be from the growth of iron bacteria occurring during temperature set back used when out of town.

A3: Well, I'm pleased, even if you aren't! The powered anode is designed to eliminate rotten-egg odor, and it seems to have done that. Other odors present more of a mystery, but we like to solve those here, too. But I'm not sure that hydrogen peroxide will fix this. If it does, that will be interesting too. Rotten egg odor comes from interaction between anaerobic bacteria often found in well water, sacrificial anodes, and sulfates in the water. Peroxide works because it introduces oxygen to the water and kills anaerobic bacteria, that don't like oxygen. But against a metallic odor? Don't know. -- Randy

A4: Hello: Iron in the water seems to be a fairly common problem. Here's a link to some interesting discussion. http://www.ag.ndsu.edu/pubs/h2oqual/watsys/ae1030w.htm -- Larry (8/8/2010)

Q3: Thanks for alerting me to the great reference material. Reading about stains to expect from iron & manganese content in well water rang a bell. Rings observed recently in less active toilet bowls indicated the possibility of significant manganese, in addition to the known iron. Had the raw water professionally tested and found magnesium also to be present. As per the reference material's thoughts on ion-exchange units, I followed the softener (one year old) manufacture's recommendation to semi-annually "power clean" the resin bed using Iron Out. At this point both the stains and odor have disappeared. Hope this turns out to be the long-term solution.


Bad Odor and a Sewing Machine

Q: I just moved into a house with a 3-year-old AO Smith Promax gas water heater (XCV 40 100). There is a bad smell coming from the top of the tank. The gas company came to check it out and said it is not CO and is not a gas leak. It's smelling up our whole basement. The water from our taps smells fine and is the right temperature. Any ideas what the smell might be and how to get rid of it? A possible related symptom is that we had a tremendous amount of rust colored fine sandy sediment come from the hot water taps (especially the tub). I flushed the tank and then ran the hot water in the tub for about 30 minutes and now there's almost no sediment coming out.

A: Two things come to mind. One is a question of whether to vent up to the roof is working correctly. When a heater fires up, initially it will spill fumes from the draft hood (at the top of the heater) for a few seconds and then draft will be established pulling all fumes up and out. If you can feel heat around the draft hood for any length of time, there is either a venting or house air pressure problem. The other thought is something in the combustion chamber or flue that's not supposed to be there. An unfortunate animal comes to mind :? Have a look in the combustion chamber and remove the vent pipe and pull the baffle out to make sure all is clear. If you see any amount of soot, things are not working as they should. -- Larry

A1: I thought it a good time to relate a story an acquaintance told a few years ago. She went out one day and found flames billowing out of the combustion hatch of her water heater. Upon closer inspection, she found a dead -- and thoroughly roasted -- mouse lying on the burner pan. -- Randy

Q1: For those of you in deep suspense wondering what's causing the odor here's the probable cause you never suspected. On a shelf next to the water heater was a portable sewing machine in a cloth-covered carrying case. It was given to my wife by her parents at the same time we were moving into this house. The machine had been in their basement when the sewers backed up in a big storm and the basement flooded. The case smelled like sewage. The smell was bad but only when you got up close to it. Apparently storing it next to the water heater magnified the odor and distributed it through the basement. I removed the sewing machine from the basement and the odor has dissipated significantly. My guess is that was it and now we are just smelling the remaining traces. (10/25/07)


Rotten Egg Odor and Water Softeners

Q: OK, friends, I have been dealing with a "small" problem with our new house's water. It's hard water, has 0.6 ppm iron, but mostly the hot water reeks!! I called a water treatment specialist, a plumber and have interfaced with other distributors from off the Internet. I finally rolled up my sleeves late last night and took action. I was driven to evaluate the anode rod by the heater's own manufacturer & the plumber by their technical bulletin http://www.hotwater.com/bulletin/bulletin22.pdf. But they did not reccommend I remove the anode rod -- just buy shock-chlorination system.

So how do I address the "activated hydrogen from cathodic reactions within the tank" -- one of the requirements for this harmless bacteria to survive? Well, I found a Web site with nothing to sell ... just wanted to save landfill space by educating consumers on some simple water heater tactics.... http://www.waterheaterrescue.com/index.htm. And I found a special description involving the anode rod and the bacteria.

Quick fix: Your water stinks and discolors your laundry. Shut off the cold water valve (see Knowhow), drain some water from the tank, open one of the nipples, and dump in about four pints of hydrogen peroxide. Close everything up and let some water run from all spigots and taps. The smell is caused by anaerobic bacteria. The peroxide adds oxygen to the water, killing them. Running the water gets the peroxide into your pipes and kills the bacteria there.

Complete fix: The peroxide will kill the bacteria for the time being, but more is coming in all the time and the next time you leave for a few days, the problem will return. One solution is to replace the magnesium anode -- which reacts with the bacteria to make the stinky hydrogen sulfide gas -- with a zinc rod. The other fix is to buy a power anode rod. The sacrificial anode's reaction with steel is an electrochemical reaction. Current actually passes between the two metals. A power rod duplicates the reaction by feeding current into the tank from an electrical element. There is nothing for the bacteria to react with, and since the rod isn't "sacrificial," it may never fail. Familian is a plumbing wholesaler. Your local store can order a power rod from it. Suggested retail price is about $60. Familian's Bay Area number is 408 899 4500. Editor's note: This no longer applies. Familian was bought by Ferguson, which doesn't stock power anodes and knows nothing about them.

So late last night I did this ... removed Mag anode, drained tank, added six pints of peroxode, filled tank, ran hot water taps until air was out & went to bed. When I took my shower this morning, there was an initial period of greenish opaque water and blackish sediment, but then the water cleared up and there was NO SMELL!!!

The hot water didn't stay hot forever so I guess I need to check the bottom heating element ... a small price to pay. But it appears I have found a solution to our smelly problem. I will not replace the anode rod for now, so when the bacteria return there will be nothing for them to make H2S gas from!! I may continue to dose the hot water heater with peroxide as I am sure some segments or sediment from the anode rod is on the bottom of the tank, But this problem has been reduced from a $2,100 franchised treatment system to $6 of peroxide!

A: Glad we could be of service. And glad you actually READ my site instead of immediately e-mailing me, as some people do. But don't leave your anode out permanently. Your tank absolutely will rust out if you do. (1995-2000)


Q: I was searching the Internet for some information on water heater problems and came across your Web site information. I was very interested in everything you had to say, particularly about anode rods. However, I am confused about a recommendation. I recently had a water heater replaced by a company, and soon began noticing the smell of phosphorous or sulfide. I called the company back and they came and simply removed the anode rod, stating that the rod was not necessary.

According to your articles, the rod appears to be very necessary, and I will be calling the company back. However, in one part of your article, you warn against ever installing aluminum rods. Under your "quick fix" however, you suggest that a solution to odors is to install a zinc/aluminum rod. Is the zinc/aluminum rod as harmful or toxic as a complete aluminum rod? Thanks for your information .... It is very helpful and well written!

A: Call it the lesser of two evils. We aren't fond of aluminum, but if you have stinky water, it IS one possible solution. And yes, if they removed your anode and put nothing in its place, they signed its death warrant. It won't fail tomorrow, but somewhere down the line it will rust out. I believe our site also offers other solutions, such as a special anode from American and the power rod kit. Consider those, too. (We no longer know where to obtain power rod kits) (1995-2000)


Q: For ten years I had to clean sediments from the bottom of HWH twice a year. 1999 got new HWH and installed water softener. Anode rod went bad (about 3-4 years later), and replaced it due to stinky water and water was also cloudy. This past week after 90 days with new anode rod cloudy stinky water came back and anode rod badly decayed.

Called Kenmore about resin tank being bad, they took offense and told me salt water does not affect the aluminin anode rod I replaced 90 days ago. Also they said the water softener should have very little salt going into HWH. PH of water is 7.2 and the hardness is 223ppm/liter. Dividing with the magical 17.1, leaves the hardness setting on softener at 13.

Now on the other side, my sink sewer line to the septic, which hot is softened, cold is not, there is a white substance that muratic acid, drano etc.... have not been able to disolve the white material. I have tried several places to get answers to my problems and nobody wants to get into it. I am not sure what is going on for the aluminium anode rod to go bad that quickly.

Yes, I have read almost every thing here on your web site and mine just doesn't exactly fit just one problem. Kenmore keeps telling me that their water softener does just that, takes out calcium, limestone etc... couldn't believe they told me salt water does not affect aluminium? Has anybody come across a similar problem.

A: Naturally soft, (like rain) water has little mineral in it. "Softened" water has had the hardness exchanged for salt or potassium. So, softened water is quite conductive, where naturally soft water isn't. The more conductive the water, the faster the anode wll be used up and the more likelyhood of odor. Try bypassing the softener for a few months and see if the problem becomes less complex. Also, replace the aluminum anode with one made of magnesium, or if odor is a problem use the rod made of aluminum with a little zinc. It is made just for odor. Hydrogen peroxide works well for odor too. Use one to two pints per forty gallons of storage. Hope that helps as a start. (9/15/04)


Q: We just got a new 50-gallon tank installed. The water smells like paint!! He warned us it might, but that it would go away. Is this normal and how long till it goes away?

A: Glass-lined tanks should not add any odor to the water. Often new fuel burning equipment smells as paint is heated for the first time, but that isn't in the water. Epoxy lined heaters can smell like you've described if the epoxy wasn't cured properly. If you have a normal glass lined tank that smells like paint, it may be too much pipe dope was used during assembly and it's adding odor as things heat up, but that's only a guess. One more thought; actually a question. Was any glued pipe used in installing the heater? PVC solvents could smell like paint. Otherwise, I'd contact the manufacturer and see if they can help. It may be a warranty situation. -- (12/12/04)


Q: I want to replace my existing aluminum anode rod on an AO Smith water heater. However, I am still confused on whether to use the aluminum/zinc rod or the magnesium rod. It seems the mag rod would also cause the stinky water problem.

A: Either a magnesium or an aluminum rod will cause the odor. The zinc is an important ingredient in the alloy rod. It helps suppress the odor. -- Randy (11/29/04)

 

Back to Tanklets
Home | Site Map