Three Easy Ways To Get Rid Of The Rotten Egg Smell In Your Hot Water

Jumping in the shower can be an energizing way to start your day or to relax after a hard day's work. For many it is one of the little joys in life that they take for granted. But, when your hot water suddenly begins to smell like rotten eggs, it can take all the joy out of your shower and leave you feeling stinky. Fortunately, the rotten egg smell is typically harmless and easy to eradicate. Find out where the odor is coming from and how to get rid of it and restore your water to its natural, odorless state.

Sources of Smelly Hot Water

If your cold water is fine and you only smell the odor of rotten eggs when you turn on the hot water, the culprit is likely hiding out in your hot water heater. When anaerobic (harmless) bacteria in you water come in contact with the metal anode rod, they begin to corrode the rod and release hydrogen sulfide gas, giving rise to the characteristic rotten egg smell. The anode rod is designed to corrode to prevent other parts of your water heater from corroding, so it is actually doing its job, and the odor is just a byproduct.

Ways to Get Rid of Rotten Egg Odor in Your Hot Water

There are several ways to banish the rotten egg smell in your hot water. Try these solutions.

  • Use Hydrogen Peroxide: Hydrogen peroxide is a safe and inexpensive solution that kills the bacteria responsible for creating the odor in your hot water. It isn't a permanent solution, but it is easy enough to perform that you can use it any time the odor returns. Here's how to use hydrogen peroxide to rid your hot water of the stench of rotten eggs.
  1. Purchase a bottle of 3 percent hydrogen peroxide at your local department store or pharmacy. You will need one cup of hydrogen peroxide per 10 gallons of water. If you have a standard 40-gallon water heater, you will need 4 cups (one quart) of hydrogen peroxide. Hydrogen peroxide typically comes in pint or quart containers, so you will need two pints or a one-quart bottle to treat your hot water heater.
  2. Turn the hot water heater off and allow the tank to sit, without drawing water from your faucets, until the water in the tank cools. You may wish to turn the heater off before going to bed so you can get right to work in the morning. Otherwise allow several hours for the water to cool.
  3. Turn off the cold water inlet valve to your water heater. This valve lies between your water source and the heater and is typically located at the top of your water heater.
  4. Attach your garden hose to the drain on the bottom of the tank and drain off several gallons of water. Alternately, you can draw water from the hot water heater by turning on your hot water faucet, but it is more difficult to tell how much water you have drawn from the tank, as the reservoir of water in the pipes from the tank to the heater may mislead you.
  5. You will need to disconnect the cold water pipe on your water heater and pour the appropriate amount of hydrogen peroxide into the water heater. Reconnect the pipe and turn your cold water supply back on to refill the tank.
  6. Let the heater sit for several hours. The peroxide will kill the bacteria in your water heater and eliminate the odor of rotten eggs. Peroxide degrades to hydrogen and water as it sits and does not pose a health hazard.
  • Use Household Bleach: Household bleach can also be used to kill bacteria inside your water heater.
  1. Follow the procedure for draining water from the tank and adding hydrogen peroxide, substituting 5 ounces of bleach per gallon of water. A standard 40-gallon tank needs about 1 ½ gallons of bleach.
  2. Turn on all the hot water faucets in the home and let them run until you smell bleach. This will fill all the pipes with the bleach solution and kill any bacteria in the pipes, too.
  3. Turn off the faucets and let the heater sit for several hours.
  4. Drain the hot water heater and let it refill. Let the water sit for an hour or more and drain it again.
  5. Repeat refilling the tank and letting it sit a second time.
  6. Open all your hot water faucets and let them run until you can no longer smell bleach.
  • Replace the Anode Rod: Sometimes, replacing a magnesium or aluminum anode rod with an aluminum/zinc alloy rod will correct the problem. This may be necessary if you are using a water-softening system. Softened water speeds up the anode consumption and causes the release of more odor-causing gases. Replacing the rod generally eliminates the odor. 

While these solutions may solve your problem, they are not a permanent fix. You may need to repeat the procedure after vacations when the tank is not active, or you may need to replace the anode rod periodically. If you need help replacing the anode rod in your water heater, or if your water heater requires other repairs, contact a company like StateWide Mechanical II Inc. for assistance.