How To Get Rid Of Rotten Egg Smell In RV Water Heater


Published Date: October 17, 2020

Last Updated on October 24, 2022 by camper front

Although an RV cannot function like the “normal” housing built with sticks and bricks but then, you definitely still crave some normalcy with an RV.

Sometimes it doesn’t just work, and you might have to deal with some horrible smell during your use of an RV, one of which is sulphuric rotten egg smell.

And the culprit is usually the holding tanks or your RV water heater, but in this article, we are going to talk about how to get rid of rotten egg smell in RV water heater.

What Causes Rotten Egg Smell In RV Water Heater?

The primary culprit of the rotten egg smell in water lines is the reaction of sulfates and microorganisms in the water; this creates a terrible smell in the hot water tank or RV water heater. To find out the exact source of the smell, run the cold water and find out if it has an odor and not just the hot water.

Run the hot water from one faucet, then move to another, then run the cold water; if the cold water still has an odor, then the source is in the water tank. If the hot water alone has the odor, then the problem is in the RV water heater.

So many things can cause the egg smell in your RV water heater. If the odor is present only in your hot water, it is usually caused by the presence of sulfate-reducing bacteria in your hot water tank.

It can also be caused by a chemical reaction between your magnesium anode and the hot water because as the anode corrodes, it leaves the heater largely corrosion-free in the process and this leads to a reaction between the rod and sulfate from the water thereby causing the water to smell.

If the odor is present in both hot and cold water, the problem is usually caused by the presence of hydrogen sulfide gas in the water underground. And it is usually from your water supply, which can be quite expensive to fix.

Read Also: Is It Good to Clean RV Toilet with Bleach?

How to Get Rid of Rotten Egg Smell In RV Water Heater

What Causes Rotten Egg Smell In RV Water Heater

There are easy ways to get rid of that horrible smell; if it is caused by a bad anode rod, you need to identify the damaged rod and replace it. And if it is caused by a bacteria, you can fix that with hydrogen peroxide.

How to Detect a Bad Anode Rod

The anode rod is actually the main component of a water heater that attracts corrosive elements and depending on your type of RV water heater, one or two anode rods may be present.

One anode rod can last up to ten years or just a couple of years, depending on your water quality and usage. But on average, a rod is completely dissolved within 4-5 years.

If you have had your RV water heater for a while and haven’t changed the anode rod, it should be the first thing you look at.

In order to be able to inspect and possibly replace your anode rod, you will need a couple of tools;

  • Garden hose (for draining)
  • Pipe wrench
  • Socket wrench
  • Thread sealing compound
  • An extra hand to help hold the tank in place during this process.

But before you do any work on your heater, you want to make sure the power is turned off. This is because the heating element can be damaged if it comes into contact with air while you carry out this operation.

The next step is to turn off the cold water supply to your heater and then connect the hose to the drain valve at the bottom of your tank.

You can also drain the water into a bucket or place the hose into a drain, but you have to apply caution when handling the hose because it gets really hot during this process.

Next, locate the anode rod, which looks like a hexagonal plug and is usually located at the top of the tank, but can also be attached to the side of the tank.

After draining the water until it’s below a side-mounted rod, you can turn off the drain valve and allow the hose to become cool to the touch before removing it.

You will then need to turn on a hot water faucet in order to relieve the pressure inside the tank so that you can safely remove the rod, and you will need a socket wrench for this and may also need to use your hands to loosen the head a little.

You might also need to tilt the rod as you remove it if there’s not enough clearance.

Even before removing the rod totally from the tank, you will be able to see the amount of corrosion on it; a bad anode will be mostly or entirely eaten away while a healthy rod will be thick and hard to remove.

After removing your bad anode rod, you will need to spray fresh water into your tank with your freshwater hose. Put the hose in the tank, and fill the tank with water, and then let the water rush out with the sediment and debris.

You can also use a flushing wand which helps to increase the pressure of the freshwater and push it deeper into the part of the RV water heater tank that is below the drain, and they help to loosen any calcified build-up inside the tank.

After flushing the tank, you need to put hydrogen peroxide into the tank and eliminate the egg smell. To put the hydrogen peroxide inside the tank, you might need a polyethylene tube with a J-shaped funnel.

Once you fill the tank with the peroxide, you need to fill the RV water heater with water via the camper fresh water tank and let the RV water heater sit with the hydrogen peroxide. After letting the peroxide sit for some minutes, then drain it once more.

Now you need to start the process the anode rod; if it is bad, you will need to replace it, and you can choose to replace it with a different type of material of anode rod.

There are Flexible Anodes are the same as regular anode rods, except they are able to bend. This makes it easier to replace them in tight spaces.

There are also Powered Anode rods, which are a newer solution that emits electrical pulses that helps to increase the rod’s anti-corrosive efficiency.

For the metal of the rod, there are three major types:

Zinc: This has natural anti-fungal properties that help to reduce the amount of bacterial growth in the tank; if you have a frequent problem with smelly water, then this is the best option for you.

Magnesium: This is the most common type of anode rod metal, they work best and offer many health benefits, but they tend to degrade faster. If you don’t experience rotten egg supply frequently, then you can go for this.

Aluminum: This is the last type of anode rod metal; they don’t degrade quickly and are also the cheapest. However, they are less effective compared to magnesium rods.

If you intend to flush your RV water heater with hydrogen peroxide quite frequently or if the rotten egg smell is simply caused by a bad rod, then you should definitely go for this.

Read Also: What is The Amount Antifreeze To Put in RV Holding Tanks?

How to Add Hydrogen Peroxide to Your RV Water Heater

How to Add Hydrogen Peroxide to Your Water Heater

If your anode rod is in good shape and you are experiencing the smell due to bacteria, then you have to Perform a 3% hydrogen peroxide flush that will help get rid of anaerobic bacteria.

  • First, turn off the power of the heater
  • Close the main shut-off valve
  • Open both a nearby hot water tap and the temperature and pressure relief (TPR) valve
  • Drain the tank until the water level is below the TPR valve, then shut both off
  • Add some 3% hydrogen peroxide(approximately 1-2 quarts per 40 gallons, adjusted according to your tank’s capacity)
  • Open the cold water intake valve until the tank’s filled
  • Shut the valve and let the solution sit for a while
  • After waiting for a few hours, you can then flush the tank by turning the cold water valve and hot water tap back on
  • Then Allow the tank to refill as you usually would after a flush
  • If the water still smells, repeat the process
  • When the hot water taps are flowing normally, restore power to your tank


There’s nothing more infuriating than trying to get a warm bath on a chilly day while camping, and you are ridden with smelly and unclean water.

Knowing how to get rid of rotten egg smell in RV water heater will help you save the day and allow you to get your much needed warm bath.

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