Dealing with a foul odor from hot water (no problem with cold water) that coincided with installing a new anode rod in the water heater. (Original info here: https://www.askmehelpdesk.com/showth...ight=foul+odor ) Got a "premium" anode rod and had the same problem. Experiments with pieces of the old rod and water drained from the heater did NOT produce any odor. Online searching led me to suspect Desulfovibrio.

Pulled the new anode rod, scraped off some of the white coating that formed (calcium?) and added 2 pints of bleach before reinserting the rod. "Pulled" chlorinated water through all faucets (including washing machine and dishwasher) and let everything "cook" overnight. It took a while to clear the chlorine smell but the foul odor is completely gone.
Since the Desulfovibrio probably lives in the well water, I expect that a new colony will grow in the water heater unless I develop an effective maintenance routine to prevent it. Questions:
O Will "cranking up" the water softener to get softer water reduce/eliminate the calcium on the anode rod? Reduce/eliminate the Desulfovibrio?
O Should I be scraping the calcium off the anode rod?
O Since I don't want to turn up the temperature in the water heater (can't scald the kids!), what kind of things should I do?
- Regular (monthly?) chlorine in the water heater? Can I use swimming-pool chlorine pellets?
- Would hydrogen peroxide be as/more effective?
- Would a curved cold-water-inlet tube help?
- Is there something else I should do?
- Would replacing the conventional water heater with an "on demand" system solve this problem?

Thanks.

Quote:

---

Originally Posted by adlowe

Dealing with a foul odor from hot water (no problem with cold water) that coincided with installing a new anode rod in the water heater. (Original info here: https://www.askmehelpdesk.com/showth...ight=foul+odor ) Got a "premium" anode rod and had the same problem. Experiments with pieces of the old rod and water drained from the heater did NOT produce any odor. Online searching led me to suspect Desulfovibrio.

Pulled the new anode rod, scraped off some of the white coating that formed (calcium?) and added 2 pints of bleach before reinserting the rod. "Pulled" chlorinated water through all faucets (including washing machine and dishwasher) and let everything "cook" overnight. It took a while to clear the chlorine smell but the foul odor is completely gone.
Since the Desulfovibrio probably lives in the well water, I expect that a new colony will grow in the water heater unless I develop an effective maintenance routine to prevent it. Questions:
o Will "cranking up" the water softener to get softer water reduce/eliminate the calcium on the anode rod? Reduce/eliminate the Desulfovibrio?
o Should I be scraping the calcium off the anode rod?
o Since I don't want to turn up the temperature in the water heater (can't scald the kids!), what kind of things should I do?
- Regular (monthly?) chlorine in the water heater? Can I use swimming-pool chlorine pellets?
- Would hydrogen peroxide be as/more effective?
- Would a curved cold-water-inlet tube help?
- Is there something else I should do?
- Would replacing the conventional water heater with an "on demand" system solve this problem?

Thanks.

---

It would appear that the problem started when you replaced the first anode rod. If you have the Desulfovibrio bacteria in your well then it's a well problem and not a water heater one but since you say you have sweet cold water it's doubtful that's the source . Have the hot water tested and nail down the source. By "curved water inlet tube" are you referring to the dip tube that directs cold water to the bottom of the tank? Where would I find one and how could it help with the smell? Cheers, Tom

Sometimes plumbers replace one pipe (the cold water pipe for example) and not the other. Rust may have developed on any galvanized piping coming from the heater and may be causing the odor.just a thought. :p