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The first thing in the morning, after that nice and quality sleep, is a glass of water. Often happens that the tap water that most of us reach for in the morning, gives an odd smell, rather like a rotten egg. Now you start opening the windows and calling friends. But no one knows. Your Hot Water Smells Like Rotten Eggs?  Here are the best ways on how to eliminate that smell from your water.


Wondering Why Your Hot Water Smells Like Rotten Eggs?

Hot Water Smells Like Rotten Eggs - bad smell

There are not that many odors in water, so there aren’t any in the water heaters. But sometimes there is a very familiar odor, the rotten egg smell. 

Nothing to panic about, it comes out of your faucets and fixtures when the water is running. 

Sulfate bacteria that develop inside the tank is the cause of this smell. This issue arises when hot water is left in the tank for too long alloying the bacteria to build up in the water. 

This problem is also common in households that use well water and are not applying the proper volume of chlorine in the well. 

The chlorine helps defeat the bacteria responsible for the odor.

The rotten egg smell in water is also caused by water softeners and the magnesium anode rod within the water heater. 

After some time of using the heater, the soft water starts to break down the magnesium and create sulfate gas inside the heater. 

If this problem occurs, you will see water and air coming out of the faucets and a sulfate smell to the water.

So, the hydrogen and sulfur combine to form the hydrogen sulfide gas that gives off the rotten egg odor.  

Using the water heater daily may reduce the problem.  

The following steps may also be helpful in clearing the water lines and the water heater.


How to Flush the Hot Water Heater And Eliminate The Rotten Eggs Smell


Step 1: Open All Faucets

  • Turn all faucets in your home fully open. Let the water run for 10 minutes, then turn the water off.  This will clear out all the water from the pipes in your home. 
  • If the odor is still present, go to Step 2.

Step 2: Monitor

  • Don’t cut the incoming water supply.
  • Connect the hose to the drain valve on the lower side of the water heater and let the other end of the hose pump water outside. Open the valve and drain the water heater.
  • After 10 minutes take a look at the water coming out of the garden hose. If the odor has passed it is time to get a white cup. Use it to get a sample from the water coming from the hose.
  • Let the cup settle and take a look at it. If there are no particles that are settling to the bottom, turn off the valve on the bottom of the heater, disconnect the hose from the valve and return the heater and hose to normal.
  • If there ARE particles settling to the bottom of the cup, continue to let the water run.  Check the water every 10 minutes until no particles are present in the cup.  Then turn off the drain valve on the lower side of the water heater.  Disconnect the hose from the valve and return the hose to normal use.
  • But, if there are particles inside the cup, let the water run a little longer. You can check the water every 10 minutes just to make sure that it is working.
  • When you are done and there are no particles in the cup. Return everything to normal.
  • This procedure should be repeated every 6 months, so the water heater was an extended or normal lifespan.
  • If the odor still persists, the hot water heater will need to be disinfected to kill the bacteria producing the odor.  Follow the instructions in Step 3.
  • But, if the odor isn’t gone, the water heater will have to be disinfected so that the bacteria that produce the odor are exterminated. Follow the steps in Step 3.

Step 3: How to disinfect the hot water heater

  • You can start by putting the water heater on high for 2 hours. This will kill the sulfate bacteria because they can’t survive in high temperatures.
  • The next step is to flush the water heater. With this, you will remove the bacteria from the heater, as shown in Step 2 above.
  • CAUTION:  The water heater must have an operable pressure relief valve, otherwise this method of treatment may be dangerous.  The temperature setting must be reduced following treatment to prevent scalding hot water and to avoid high energy costs.
  • If the odor is still there, then chlorination of the water system will have to be performed and for that follow Step 4.

Step 4: How to chlorinate the hot water system

  • You have to turn off the water supply to the water heater.
  • Turn the switch to the “Pilot” position on a gas water heater
  • Or, turn off the circuit breaker on an electric heater
  • Make sure to relieve the tank pressure by opening a hot water faucet. It has to stay open for at least 30 to 40 seconds. And there will be no water flowing at this point.
  • The piping on the top of the heater, the one that is responsible for the cold water coming in, needs to be disconnected from the heater.
  • You have to drain 1 gallon of water from the drain on the lower side of the heater.
  • For the next step, you will need a household bleach. You will have to add the liquid bleach to the heater at the cold water inlet. You will need to use a gallon of bleach for an 80-gallon water heater.
  • Next, connect the cold inlet beck in place.
  • Turn the water supply to the heater back on.
  • Open all the faucets in the house. You will smell the chlorine bleach in a couple of minutes.
  • You have to let the chlorinated water remain in the system for at least 8 hours. And I think I don’t have to remind you not to use the water at this time.
  • After those 8 hours are due, flush the water from the water faucet until no chlorine odor is left.
  • The last step for a gas water heater is to turn the control back to the “On” position.
  • And for an electric water heater, you can turn on the circuit breaker again.


How to prevent the hot water that smells like rotten eggs from developing in your water heater?

One of the best ways to prevent this issue from happening to you is to ensure that you never leave water sitting in the heater for longer periods of time. 

For example, if you are going away from home for more than two weeks or if you are planning on going on a long vacation or be away for some time. 

At these times you have to turn off the gas to your water heater. 

Coldwater can sit in the tank and not build up any bacteria because the cold water doesn’t eat up the heater. If you want to know the details check the 4 steps above and start cleaning your heater.



You need to keep in mind that a rotten egg smell can be prevented if your local water supply quality is reasonable. 

As the article above mentioned, softened water plays a big part in producing bad odor in the taps. To prevent the smell regularly check the anode rod and replace it if need be.

Regularly flushing your tank with hydrogen peroxide can help remove the bacteria before they get started to build up in the tank and start to release the unpleasant odor. Flushing the tank regularly is also a very good way to get rid of any sediment or buildup of bacteria.



Your water heater can sometimes have that odor that we all hate. But after reading and following this article you can successfully do it all on your own. 

In only a couple of steps above, there is enough information to prepare you for any outcome and any difficulty you have at night. 

It starts with the easier, Step 1, to the more complicated, Step 3 and Step 4, steps. But, in the end, we all get to be rid of that pesky rotten egg smell that keeps appearing in your water heater.

It might be a good time to think about upgrading your home with a whole house water filter. Check our article on the best whole house water filter and find the one in all solution to your water problems.