GSW Bacterial Reaction with Anode Rod

GSW water heater emits a rotten egg or sulfur smell from hot water taps

Advertisements

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Advertisements

Possible Causes

Magnesium anode reacting with sulfur bacteria, Stagnant water in tank, High sulfate content in water supply

How to Fix / Troubleshooting

Safety: Turn off power or gas before treatment. Follow chemical handling precautions if disinfecting.

  • Flush the tank: Drain and refill the heater to remove stagnant water.
  • Disinfect (plumber-level): A plumber can chlorinate the tank and plumbing system to kill odor-causing bacteria.
  • Change anode type: Replace the magnesium anode rod with an aluminum/zinc anode designed for odor reduction, using a GSW-compatible rod.
  • Maintain temperature: Keep the heater at or above 60°C (140°F) periodically (with mixing valves for safety) to discourage bacterial growth, following local codes and scalding precautions.
Advertisements

Repair Difficulty

Hard 4/5

Required Part

Anode Rod
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements