8 (Easy Steps) on How to Add Hydrogen Peroxide in Water Heater

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We experienced showering and we smell a faint amount of sewage water in our bathroom. We start to think that it’s the water reacting to our floor tiles, but it’s not.

Then, one tired evening we decide to take a bath and help ourselves with some relaxation, only to fill the tub with a heightened scent of dirty water. That is not exactly because our water supply is contaminated, it could be caused by our water heater. How to add hydrogen peroxide to water heaters is a great knowledge that can help us keep the contamination away from our heated water.

If our cold water starts smelling like sewage, then there is a big possibility that the water supply is contaminated. However, if it starts happening to our heated water, then there must be a reaction happening within our water heating system.

Softened water can sometimes emit this disgusting smell. Usually, softened water accumulates hydrogen sulfide gas that gives off that dirty water scent.

What is softened water? This is a type of water that was treated to remove calcium, magnesium and certain metal cations in hard water. It makes use of lime softening or ion-exchange resins that are achieved by using nanofiltration or reverse osmosis.

Anode rod is a part of our water heater system that draws corrosive agents in the water. Over time, the anode corrodes, concentrating all corrosive agents to itself making the water heater clean.

The role of anode rod is to become sacrificial, absorbing or attracting corrosive materials in the water. However, the anode rod will soon look like it has been eaten by bacteria. Once it has nothing left, it will start emitting a smell that goes to our heated water. This can be caused by a reaction between the rod and the sulfate from the water therefore making the hot water have its unbearable scent.

The most common type of anode rod that comes with our water heater is aluminum. Aluminum corrodes the slowest but it is meant to be paired up with hydrogen peroxide to remove the sewage scent from our heated water. The reason why aluminum is packaged together with our new water heater is because it is very cheap. If the water sewage smell becomes very strong and unacceptable, changing the anode rod is the step to take.

hydrogen peroxide to water heater

However, the use of hydrogen peroxide is to combat Sulfur Bacteria. Sulfur Bacteria is natural to our water supply. When it comes in contact with our water heater it can make it its breeding ground, therefore increasing hydrogen sulfide gases. In order to eliminate the smell caused by bacteria, add hydrogen peroxide in cleaning the tank out.

Here are 8 easy steps on how to add hydrogen peroxide in our water heater:

  1. Shut it down. Do not work repairs with anything electrical without shutting it off. Same goes with gas water heaters. We can turn off the electrical water heater through the circuit breakers or if it is an easy plugged in type to electrical sockets, please unplug it. For gas, make sure that we turn it off from the pilot.
  2. Drain thoroughly the water heater tank and close the valve after we have drained. Before we drain out the water, make sure that it has cooled down to avoid third-degree burns.
  3. Make use of 3% hydrogen peroxide. An exact measurement of 2 quarts per 40 gallons should followed. It will still depend on the size of our water heater tank. Add it in our tank.
  4. Open the cold water supply and fill up the tank.
  5. Let the water seep in with the hydrogen peroxide. Do not turn on the heater yet. This is to let the hydrogen peroxide take care of the nasty smell. Let it sit for about 2-3 hours to have its full effect.
  6. Flush out the tank. After waiting 2 hours, turn on our heated water faucet and our cold water valve and flush out the tank. This will clean not just the tank but also our pipes.
  7. Fill up the tank. When we’re no longer smelling the dirty water scent, we can fill the tank up once again for usage. Test the scent from the hot water faucet. If the scent is still lingering, keep on flushing out the water heater tank.
  8. Turn the power on. Once it’s all done, turn the power supply on back to our water heater. Observe if the smell has been removed from the heated water.

Contrary to popular belief, heating does not always kill bacteria. In this case, sulfur bacteria thrive in heated water tanks that populate over time creating sulfide gas. How to put hydrogen peroxide in our water heater is a learning that will make life easier for we when cleaning out our water heater tank. It is advisable to maintain our water heater by performing a routine clean-up in its tank at least once a year. Not only will it make our water heater last longer but it will keep our hot water free from corrosive agents and free from sulfur bacteria that causes that dirty water smell.

Hi, my name is Alex Sayad and I’d like to welcome you to DD Counter Measures! Ever since I started my family, I’ve spent countless sleepless nights worrying about how to keep them safe. So, during those nights, I went online and read about home improvement guides and security systems. After a while, all my friends started coming to me for advice and tips on how to protect their homes. Seeing how much I loved talking about it and sharing my knowledge, my wife suggested that I create a website. That’s how the idea of DD Counter Measures was born. Now, after a few years of hard work, I’m happy to say that this website has grown into something I never imagined possible. We have built a community of writers and readers who are dedicated to sharing their knowledge on home security, improvements, tools, and much more. I hope you fall in love with this website while reading it as I do every day while writing for it. Enjoy!