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Plumbing Emergency: What To Do During a Flood



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Plumbing Emergency: What To Do During a Flood

Rotten-Egg Smell In Water Heaters: What Causes It And How To Treat It

by Melvin Owens

Have you ever noticed an unpleasant rotten-egg smell in the water coming from your water heater? That is the smell of hydrogen sulfide gas. However, there is no cause for alarm as the gas is usually present in low volume, and hence, carries little threat. Concentrations of as little as 1 parts per million can trigger the pungent smell of hydrogen sulfide.

Even though the gas is harmless in low concentration, it must be irritating to inhale it every time you fetch water from your water heater. Therefore, there is a need to remove it.

What Causes The Smell?

The smell is caused by the actions of Divibrio Sulfurcans, bacteria that are found inside the heater's tank. The bacteria convert sulfate in the water into hydrogen sulfide, which possesses the characteristic rotten-egg smell. Despite the presence of bacteria, there are other three conditions which must be available for the gas to be produced; there should be high sulfate content in the raw water, a low volume of oxygen, and presence of hydrogen gas.

The gas may also develop due to the inactivity of the water heater. Therefore, try to use your heater on a regular basis.

How Do You Get Rid Of The Smell?

There are two ways you can safely try:

Flush out the hot water heater

  • With the incoming supply of water still turned on, connect your garden hose to the drain valve of the heater. As for the other end of the hose, run it outside and open the valve to let the water out for 10 minutes.
  • Collect the water coming out of the garden hose in a white cup and look for particles. If no particles are visible, turn off the drain valve on the heater and disconnect the hose. However, if you are able to see some particles at the bottom of the cup, let the water run for a few more minutes.
  • Check the water for particles after every ten minutes. When you collect clean water, disconnect the hose and return it to its normal use.

If you want your water heater to be around for a long time, repeat the procedure after every 6 months.

Disinfect the hot water heater

  • On your water heater, turn the temperature settings to HIGH for at least two hours in order to kill the bacteria.
  • Flush the water heater using the garden hose method to get rid of dead bacteria. After treatment, remember to reduce the temperature setting to prevent scalding hot water.

If the temperature scale of your heater is in readable units, turn it to 160 degrees so as to kill the bacteria.

But if the smell persists, it may not be a bad idea to contact professional plumbers