Dealing With Hot Water Tank Odors

Foul odors aren't something you'd expect when you open your hot water tap. However, it's not out of the ordinary for odors to take hold within the tank. This can make it nearly impossible to cook, wash or run appliances reliant on hot water without leaving strong odors behind. The following explains what could cause bad odors in your hot water tank and how you can get rid of them.

Pinpointing the Cause

There are three things your water heater needs to give off that rotten egg smell at the taps: sulfates, hydrogen and bacteria. Sulfates, a combination of sulfur and oxygen, naturally occur in the water your hot water tank uses. There are also plenty of anaerobic bacteria in your hot water tank. As the bacteria consume the sulfur, chemical changes convert the natural sulfates into hydrogen sulfide.

As you've guessed, hydrogen sulfide smells a lot like rotten eggs – which is exactly what you're looking to eliminate from your hot water taps.

Try a Little Chlorination

To get rid of the bad odors, you'll need to deal with the bacteria present in your hot water tank. Add a 1/2-gallon of bleach to the hot water tank and allow it to sit overnight. You can also use a couple of pints of 3-percent hydrogen peroxide as a non-toxic alternative. Don't forget to run a small amount of the solution through the hot water lines (by opening up the hot water taps). When you wake up, you can flush the solution out of the hot water tank.

Turn Up the Heat

To lessen the likelihood of scalding during use, the Consumer Product Safety Commission (CPSC) recommends that your hot water heater be set at 120 degrees Fahrenheit. However, you can crank that setting up to 140 degrees for a few hours to kill off bacterial growth in the hot water tank. Just remember to turn down those settings before you use your hot water taps.

Upgrade the Anode Rod

Most hot water tanks come equipped with magnesium anode rods to prevent sulfates from corroding the tank from the inside out. The magnesium metal essentially sacrifices itself to convert potentially harmful sulfates into relatively harmless hydrogen sulfide. Unfortunately, this also gives bacteria within the tank a hearty meal to dine on, generating hydrogen gas in the process.

You could stop this from happening by removing the existing anode altogether, but that will just make your hot water tank rusty and likely void your warranty in the process. Instead, you may want to install an aluminum-zinc alloy anode. Unlike magnesium, the alloy offers natural anti-microbial properties that inhibit bacteria growth.  

For more information, contact Anderson Water Systems or a similar company.