How to Prevent Plumbing Sulfur Smells | Ask This Old House

This Old House plumbing and heating expert Richard Trethewey offers remedies to prevent smelly water. (See the shopping list, tools, and steps below.)

Shopping List for How to Prevent Plumbing Sulfur Smells:
- Aluminum anode rod, used to replace magnesium rod in water heater

Tools for How to Prevent Plumbing Sulfur Smells:
- Wrench, used to remove anode rod from water heater

Steps for How to Prevent Plumbing Sulfur Smells:
1. If the sulfur smell is present in both the hot water and the cold water, call a licensed well contractor and have him or her treat the problem at the well.
2. If the odor is only in the hot water, replace the water heater’s sacrificial magnesium anode rod with an aluminum rod.
3. Sulfur smells are extremely rare in municipal water systems.

About Ask This Old House TV:
Homeowners have a virtual truckload of questions for us on smaller projects, and we're ready to answer. Ask This Old House solves the steady stream of home improvement problems faced by our viewers—and we make house calls! Ask This Old House features some familiar faces from This Old House, including Kevin O'Connor, general contractor Tom Silva, plumbing and heating expert Richard Trethewey, and landscape contractor Roger Cook.

Follow This Old House and Ask This Old House:

How to Prevent Plumbing Sulfur Smells | Ask This Old House

[PilotVBall]

You get that smell on municipal water as well. Also, you should replace the anode every 5 years.

[madonnahagedorn]

I was at a hotel in Lompoc and the rotten egg smell permeated the parking lot. It was so bad. Now I know it was the old rotted plumbing. We didn't end up staying there because our room key failed to open the door at midnight and the office was locked with no one at the desk. Maybe it was a blessing. We found a Motel 6 open and stayed there until we could clear up matter in the morning. I won't stay there ever again.

[dougheal]

I have been in the water treatment industry for almost 40 years and switching to aluminum don't work any better.

[kevinmorris]

Had our landlord replace our water heater a few months ago. The water didnt start smelling until after the new water heater was put in... Yes, its well water. Should we replace the rod on a brand new heater?

[vishalpradhan]

Live in southern maryland we get that smell coming from the municipal water

[bdog]

Good video. While on the subject of corrosion on the water tank, One thing you forgot to do, and is a required building code in all states is to use dielectric fittings. One on the cold water inlet and one on hot water outlet. The fittings in the tank are steel. When you connect the copper pipes to those steel fittings rust much like the rod you just replaced tends to build up at this point. These fittings have a nylon pressure barrier that doesn’t let the steel and copper touch. Water and metals of all types don’t get along rust always wins. We can only delay the rust but never eliminate it. That’s why the rod was invented and these dielectric fittings. To better understand this look up dielectric fittings and why they are used. Remember, these are mandatory building code requirements for all states. If not required outside of the US I would advise you use it anyway.

[cherielacroix]

I have city water and everything smells like rotten egg! The dishwasher the glass stove top the floors I am going insane! I keep my house clean but the smell is making me lose my mind! please help!! also, does this apply to city water? You said it shouldn’t but it does 🤮 or can it be something else? HELP!!

[lindaaaron]

I have well water and a tankless water. The water coming from the hot side has the rotten egg smell. I've heard a lot about anode rods on standard water heaters, does a tankless water heater have an anode rod?

[gembabe]

Plumber did exactly this and it still stinks. Maintenance came a week later and drained the water heater and put vinegar which I let sit for 5 hours. A week later it smells again. My brother is a plumber and he doesn’t even know. It’s not well water.

[FlyboyAF]

Did you say H2S isn't dangerous? lol It is definitely a health concern!

[eboniepeeples]

What if you have a new hot water tank but you are still smelling that smell?

[MaxxDoberman]

Always get good advice from these guys

[ff]

I get rotten egg sulphur smell from the cold faucet when it hasnt been used overnight or a few hours. Never comes from the hot side... so could that be Municpal water and if so, what is the solution?? Please help This old House!!

[ebenezerclark]

Fails to mention the Bacteria and legionnaires from your shower, try turning the temp up to 140oF first - Plumbers?

[mylightofhope]

I am on well water and I generally only notice it when I turn on hot water, however it is predominantly from a sink the furthest away in my master bath. I don't smell it at the kitchen, sink and maybe only slightly at the main hall bath sinks. Don't notice in shower of main bath either. I suspected hot water heater issue but couldn't figure out if that we the case then why wouldn't it be consistent through all the other places? I also couldn't tell if this rod could be something easily be replaced by the homeowner? Ingeniously I'm not going to be able to cut open my heater like that. Lol

[wisezombie]

I'm on city water and I get that smell... why is that? Mostly on Hot water side through the entire house.

[dafnichristodoulou]

that smell also coming direct from the ''main '' water city can i fix it

[rockindude]

What about the smell in the drain and not the spout? What would you suggest for that?

[williegillie]

I’m on city water and started smelling the rotten egg smell a few weeks ago. One guy I saw poured hydrogen peroxide into his hot water heater every 2 months or so. Supposedly it helped. I’m hoping to get my anode replaced. With a little luck.

[san]

the smell goes away if you put the jug of water in the fridge for a while.. no big deal.. .. very common in ottawa canada wells