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How To Get Rid Of Water Heater Odor

‘You get a pungent rotten egg smell coming from the boiling water one fine day. You detect it has something to do with the water softener installed months back. So, you call up the company and demand instant service. However, when the plumber boy arrives, he says that the issue is with your water heater. You decide to replace it based on his suggestion. Everything stays fine for a good three-four months. Then, the rotten egg-like smell of sulfur comes back. Now, you are in a dilemma – the dilemma is whether you should replace it again or beckon the company once more.’ 
Note: This post may contain affiliate links. This means that at no cost to you, we may receive a small commission for made purchases.

Understandably, the problem seems to be of a more significant magnitude than reality. You might wreck your brain by thinking about managing to afford the solution. Contrary to what you might believe, you can resolve this issue independently without any additional charges. 

What causes rotten egg smell coming from hot water? 

Suppose there is sulfate as well as some microorganisms in the water. When these two react together, you will notice the flow of blackened water or a rotten egg-like odor emanating from the water heater (see also ‘ Water Heater Making Popping Sound? ‘).

If you are confused about this problem’s source, you have to check if the same smell comes from cold water or boiling water. 

How do you check it? 

Firstly, run the faucet with hot water. Having done that, open another tap and run the cold water. If the awful odor is coming from the hot water solely, it might be because of your water heater. 

Usually, water in cities has noticeable traces of chlorine. Chlorinated water acts as the ideal water heater odor killer. Then again, in the water in some parts, the trace amount of chlorine is so low that it is almost negligible.

There is no guarantee that there won’t be a development of odor if your house is near the distribution line. The water might be odorless once it enters the pipeline at your location’s water treatment plant. However, what happens after that is not in anybody’s hand. 

If your water distribution line is obsolete, it might act as the permanent residence or breeding ground of the sulfate bacteria. Do you know what such breeding grounds lead to ultimately?

They lead to a rampant growth of bacteria, which causes depletion of chlorine and oxygen. Hence, the development of the nasty odor becomes easy.

Some actionable steps to perform

Some actionable steps to perform

Are you unsure whether the awful smell comes from the water pipes or the water directly?

If yes, go through the steps we are about to mention now.

Get a glass of water and step away from the faucet before you smell it or drink it. Doing this will help you better judge the odor’s source. If you find no nasty smell in the glass, you are sure that the issues lie in the water pipes and water drains. 

What to do if you detect there are bacteria in water pipes? 

The best way to resolve this would be by disinfecting or sanitizing the pipes. You can use soap and a brush to do it. 

What to do if the water heater is the source of all your problems with the foul odor? 

  1. You can increase the water heater’s temperature and keep it like it for at least a day, that is, twenty-four hours. 
  2. You can flush out all the pipes by keeping the hot water tap running. 
  3. Stay cautious because turning up the water heater’s temperature can be fatal. 
  4. If you detect the presence of hydrogen sulfide in the heater, immediately seek the attention of a local lab that tests the water. They will have better knowledge about the contamination of your water. 

Water heater’s pungent odor

Many people file complaints about their city water’s disgusting smell. They fail to realize that if the odor is coming from hot water only, the defect lies inside the water heater. You all know that all water heaters contain anode rods, right?

It helps in facilitating the anode-cathode reaction. If the anode’s activity is more than usual, the water heater will have an abnormal amount of hydrogen sulfide gas. Hence, there is the necessity to get a water heater odor killer. 

Quick fact:

At one part per million, hydrogen sulfide gas will give off a musty odor. Whereas if it is present in hot water at two parts per million, it will give off the sewage-like or rotten egg-like smell. 

Step-by-step guide for water heater sanitization

What is the key to the success of your water heater’s sanitization? The catch lies in adding hydrogen peroxide to the heater correctly. 

  1. Is your water heater electric? If yes, then put off the switch. If you are dealing with a gas heater, change it to Pilot mode. 
  2. Secondly, you need to find the water heater’s valve that acts as an inlet of cold water. Once you have done that, close the valve properly. 
  3. The third step is to identify the T&P valve, also known as the temperature and pressure valve. Its general location is the top portion of the heater. Once you have done the needful, open the valve and a boiling water faucet near you. Why should you do this? The reason is the proper release of the tank pressure. 
  4. Next, you have to make space for the addition of hydrogen peroxide. How will you do it? You have to drain enough water. One important tip for you – you should always keep a hose bib cap near you. Its need will arise when the drain valve suffers from leakage. 
  5. The next step is crucial. You have to disconnect the temperature and pressure valve from the heater. While you are doing that, remove the anode and detach the outlet pipe for hot water from the water heater. 
  6. Aren’t you satisfied yet? We have another tip for better and optimum results. All you have to do is check for corrosion in the anode rod. If it has rust, replace the old one with a new zinc one. You can also buy an aluminum anode rod. 
  7. You can find hydrogen peroxide at any drugstore. Buy it and add it to the water heater. The question is – how much should you add for an effective outcome? For every forty gallons of water in the heater, you need to add three percent hydrogen peroxide in two pints maximum. 
  8. The next step is all about how you can pour the required amount of hydrogen peroxide. You can either do it by pouring it into the opening of the outlet pipe or the opening of the temperature and pressure relief valve. Close them after you have completed the step. 
  9. This step is relatively straightforward. First, all you have to do is open the inlet valve for cold water. Secondly, fill up the tank thoroughly with water. Next, use your eyes and observe the level of water. Once it is up to the brim, close the valve facilitating an inlet of cold water. 
  10. You have to let the hydrogen peroxide stay in the water heater for at least three hours if you want to get a water heater odor killer. 
  11. The next few steps are essential for getting an effective result. You do realize that the hot water pipes need cleaning, right? So, let the hydrogen peroxide clean it after three hours are complete. How do you do that? Open the cold water inlet valve, and the hot water taps. Next, there will be a residue of the peroxide mixture. Drain it by using the drain valve of the water heater. 
  12. After you have cleaned the drainage valve and filled up the water tank with fresh-water, you have to allow it to live and breathe in the tank for a meager fifteen to twenty minutes. 
  13. This step can get a bit boring. It requires manual effort. After you have purified the hot water’s supply lines, you have to reuse the drainage valve. How? You have to drain the water from the water tank through this valve so that any sedimentary deposit can get flushed. 
  14. Once you have finished the previous step, close the drain valve, which you used to drain the water. 
  15. You can culminate the next two-three steps into a check-list. Those are as follows:
  • Have you purged all the air from all the hot water faucets you had opened? 
  • Have you made sure there is no air left in the water system? 
  • Have you checked for any water leakage? 
  • Have you diagnosed that the heater is operating normally or not? 

Can a water purification system act as a water heater odor killer?

Can a water purification system act as a water heater odor killer?

Suppose your hot water has an unusually higher level of sulfur-reducing bacteria and the rotten egg smell is an unbearable constant in your life for months.

In that case, it is probably time to get a new water purification system. Your plumber would be the best advisor on which type of water purification system would be the best one. 

What will happen if the water heater odor returns? 

Once you have followed the steps mentioned above, we can guarantee that the odor will go away. Sanitizing a water heater is a water heater odor killer’s perfect medium. The same pungent smell can then come back after a few weeks or maybe one month. What to do then? You have to repeat the same steps again and again.  

What are the various extra steps to get rid of the stinky odor when it reappears? 

  • It would help if you considered replacing the original magnesium anode with a zinc anode rod or an aluminum anode rod. Give it a second thought if you haven’t thought of it already. 
  • Replace your water heater with the following types of water heaters: instantaneous heater and water heaters made of stainless steel. We suggest you use a water heater without an anode rod

The Bottom Line

There is nothing as disgusting as your hot water smelling like a pile of sewage. This smell is similar to the nasty smell of rotten eggs and dirt.

If your water heater has been inactive for two-three weeks or runs on more than average low temperatures, you might face this issue. If your water tank is more than 13-15 years, you need to think of replacing it with a new one. You can’t afford to use the hot water with a nasty smell. 

We have only two things to say to you now – flush out your water heater, chlorinate it. 

Use the steps above to get your ideal water heater odor killer. 


author avatar
Charlie Hardcastle


On Key

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