What to Do When Your Hot Water Smells Like Rotten Eggs

When hot water smells like rotten eggs, it can make property owners think the system has failed overnight. In reality, this odor usually comes from chemical reactions inside the water heater rather than contamination of the entire supply. When we step into these calls, our first job is to help people understand that this problem has specific patterns, and once we identify them, we can map out what needs to happen next. Gold Star Plumbing & Drain helps property owners address the issue with expert water heater repair in Chandler, AZ, restoring fresh, reliable hot water quickly and efficiently.

How Hydrogen Sulfide Forms Inside The System

Hydrogen sulfide is the gas behind the rotten egg smell. The United States Geological Survey reports that hydrogen sulfide can occur in groundwater at levels as low as 0.5 parts per million and still create a strong odor. In traditional tank water heaters, this gas becomes more noticeable when water reacts with the anode rod. Tankless water heaters can also experience the odor if hydrogen sulfide is present in the incoming water or builds up in components where water temporarily sits. In older or heavily affected units, a tankless water heater replacement may be the most effective solution.

In some less severe cases, tankless water heater repair can tackle persistent odors and restore clean, fresh hot water without replacing the unit.

Other Factors Behind the Rotten Egg Smell

The anode rod protects the water heater tank from corrosion, but over time it can contribute to odors. As the rod reacts with minerals and bacteria in the water, it may increase the production of hydrogen sulfide, which causes the rotten egg smell. Worn or aging anode rods often make these odors more noticeable. For older units or tanks showing other signs of wear, property owners may eventually consider water heater installationto replace a system that is nearing the end of its lifespan. Targeted maintenance or rod replacement often resolves odor problems without requiring a full system replacement.

When Heat, Minerals, And Time Make The Smell Worse

Hard water can make the problem stronger. Sediment buildup warms unevenly and traps minerals that change how the tank behaves. The Water Quality Association has documented that even thin layers of scale reduce heating efficiency and cause temperature swings. These swings can bring the odor out more sharply, which leads some property owners to wonder if they are due for a water heater replacement. We evaluate buildup, age, and water quality before guiding anyone in that direction.

FAQs

Why does only my hot water smell bad?

The odor often starts inside the heated tank due to the breakdown of the anode rod, while cold water bypasses that process.

Is hydrogen sulfide dangerous?

According to the Centers for Disease Control and Prevention, hydrogen sulfide at levels normally found in household water is a nuisance rather than a health risk. 

Can flushing the tank help?

A flush can remove sediment and bacteria that make the odor stronger. It is often one of the first steps we take.

Does the smell mean I need a new system?

Not always. We test the water, inspect the tank, and look at part condition before suggesting replacement.

How long does an anode rod last?

Most rods last three to five years depending on water quality and usage.

Restore Hot Water You Can Count On

A rotten egg smell can make any property feel uncomfortable fast, and getting rid of it takes the right mix of skill and experience. We bring licensed and insured service backed by strong warranties, fair pricing, and financing options that help people move forward with confidence. Our family owned team has over 25 years of industry experience and highly trained technicians who know how to solve odor problems at the source. With over 1,400 satisfied customers, an A plus rating from the Better Business Bureau, and availability around the clock, we offer a same day service option that gets your hot water back on track without delay.

Call us today to schedule expert water heater services.