Hot water that smells like rotten eggs is usually caused by bacteria in the water heater reacting with the metal anode rod inside the tank. The reaction creates hydrogen sulfide gas, which gives off that strong sulfur smell.
First, Rule Out a Gas Leak
A rotten egg smell in the air, not just in the water, can mean a natural gas leak. If you smell it near the water heater, stove, or anywhere in the house when no water is running, leave right away and call the gas company or 911 from outside.
How to Tell If It Is the Water Heater
Run the cold water and smell it. Then run the hot water. If only the hot water smells, the water heater is the likely source. If both smell, the issue may be in the water supply or a drain nearby, and your water provider may be able to help.
Why It Happens
Many tanks have an anode rod made of magnesium. It protects the tank from rust, but it can react with certain bacteria and sulfates in the water. The smell is often stronger when the heater has not been used for a while, such as after a vacation. It can also show up after a new heater is installed, as the water settles in.
What Can Be Done
- Flushing and disinfecting the tank to remove bacteria
- Replacing the anode rod with a different type
- Adjusting the temperature setting
- Checking the heater for other signs of age
These steps involve hot water, pressure, and sometimes gas parts, so they are best handled by a professional. Removing an anode rod also takes special tools and can damage an old tank if done wrong. Help with water heater problems can include testing and treating the tank.
If the smell comes with rusty water or noises, you can ask our plumbers about your water by calling JPR Plumbing at (833) 603-1840.