sulfur smell in bath sink

My bathroom sink has a frequent but not constant smell of sulfur in the water. The toilet and shower come off of the same line, but they never smell. I am 100% positive that it is not from the drain, I have filled a glass with the water and you can smell it in the water outside of the bathroom. I am on a community well, but none of my neighbors have had any problems. The only advice I got that seemed plausible was that you can still buy leaded solder, and that someone may have redone the supply lines using it. When some mineral in the water mixed with that bit of lead it could create a smell. I don't know if this is possible or not, plumbing is not my strong suit, so any advice would be greatly appreciated!

Hi fyaym, welcome to the forum

As you say that the water of the shower and the toilets come of off the same line I am more inclined to think the problem could be at your tap system. Have you changed that lately or checked?

Thanks for the welcome

The faucet was new, I put it in soon after we bought the house, so I am not sure if the problem existed with the old one since it isn't constant. I did just check the pipes in the basement, and after pulling off some of the pipe insulation I saw something kind of strange. In between the T off the main line and the next elbow, there was a two inch piece of red rubber with a ring clamp on each end. I assume that isn't acceptable but I don't know if it could cause the problem. Right now I am renovating the bathroom and everything is pulled out so I can't try a different faucet, I wanted to fix the problem while everything was still open and easy to get to.

What is important to know is if that red rubber and its ring clamp also is on the pipe that supplies water for your toilet and shower. If it is only on the pipe leading to your sink where this problem exists I would suggest you replace this red rubber band and its clamp to plastic.

It is very important to notice if cold water smells like sulphur. If it does not, it is your annode rod in your water heater. As the annode rod ages, it creates hydrogen sulphoxide. It's just that it's more noticeable in a lav sink than anywhere else. I won't go into the reasons why this is. If your cold water does smell, it is very possible that there is a section of threaded galvanized steel pipe on that particular branch. Maybe even inside the wall. Believe it or not, if the company or person who cut and threaded that section used sulphur-lard based cutting oil the smell will never leave and actually impregnates the rubber and plastic parts of any faucet. Find the offending galvanized section and replace with approved water piping, copper or plastic, or replace your annode rod and drain and flush your water heater.

G-r-e-a-t, I hope fyaym will read this soon, thank you askaplumber1st.

Since the water is not the source, it is the drain. I had a similar problem. It was the overflow drain. It did not have a way to completely empty into the drain because the hole in the drain pipe was higher than the sink's overflow tube. Water that had collected there was stagnant and stinky.
Pour some disinfectant down the overflow for a quick fix. You can use various things, but don't use anything too caustic. If this is the problem, the caustic chemical will stay there for a long time, and could case damage to the drain pipe. Dilute bleach would work, or even hydrogen peroxide. For a better fix, you will have to remove the drain pipe and modify it to match the overflow pipe.

the hole in the drain pipe was higher than the sink's overflow tube

another little detail to pay attention to. thank you so much for mentioning this

We found out and Moen finally admitted that the small plastic lines in the new faucet does react to our well water to cause that rotten egg smell. It only was in the cold side. The hot water was fine. They sent us new lines with instructions to run bleach thru the faucets and change the lines. I did the bleach and switched the supplies so the hot water ran thru the cold side. So far so good. Now the new ones in the Kitchen are starting the same smell. We had no problem with our old faucets or any of the other old faucets in the house. It appears to be the use of plastic in the faucet itself that caused the problem. Im looking for faucets without plastic parts.

Hi Hanksan,

I have a problem identical to yours. I contacted Moen and they are sending me new plastic hoses to correct the problem. However, when I mentioned sending bleach throught the faucet, they didn't seem to know anything about that; and I talked with two different Moen reps. They said that they only recommend a 50-50 mixture of white vinegar and water. Do you have a name or extension number of the Moen rep that you spoke with? I would appreciate any info you can give me. Thanks

I am ready to junk the moen and two other new faucets and go to Chicago Faucets. They seem to be the only ones with all metal parts. It is a problem with my well water. If anyone knows of any others let me know. It is a function of the plastic reacting to somthing in the water. So I dont think the new plastic parts will help. The bleach worked fine at first with the bath room sink. Then the new ones in the kitchen started to smell the same way. I had my well chlorinated and that worked for a few months but now the bathroom one is back smelling again. My wife wont drink it. I check with the health department and they said it was ok so I let it run for a bit and drink it myself. Another case of the government interferring without full knowledge of the problems they will cause. They have to do some of this stuff to justify their existance.

I believe you have diagnosed my problem. I have Moen fixtures (8 total) and three of them, that are the same type, are giving me sulfur smells. Do you know if it is a problem with all moen fixtures or just a select few and if so what type was giving you problems.

thanks for any information