If a Hydrogen Sulfide odor is associated primarily with the hot water system, a hot water heater modification may reduce the odor or you may need to pasteurize the system. If the odor is stronger in the electric water tank, we recommend the following:
It would be advisable to check the quality of the water entering the tank.
If you have a well, we recommend that you also Shock Disinfect the well and distribution system.
If sediment is entering or leaving the system, you might want to consider a RUSCO 1-1/2-60 Hot Water Spin-Down Filter System. You would install this on the inlet side of the water-heating tank and add peroxide to aid in the disinfection process. If this does not work, try replacing the sacrificial magnesium anode rod with an aluminum anode or replace the hot-water heating tank with an on-demand system, a plastic-lined tank, or a commercial stainless-steel unit.