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4 Reasons to Replace Water Heater Anode Rod

Replacing an anode rod in a water heater could be as simple as removing the old one and screwing in the new one. Or it could mean gathering enough tools to build a house and spending hours and all your energy trying to remove a seized or broken rod.

Many of us are tempted to just leave the rod in a little longer than the recommended time; some even wonder if it’s actually necessary to replace the rod. Below, you will find 4 main reasons why it is worth your while to replace an anode rod regularly and how often you need to change it.

1. Water Heaters Last Longer With Anode Rods

Corrosion is the natural enemy of metal. Since the tanks of water heaters consist primarily of this material and are continuously in touch with water, they are very likely to rust over time. Once they do, they are unable to function properly, their lifespan is rapidly shortened, and the corrosion could potentially cause some serious safety problems and material damage.

Additionally, if the heater is gas-powered, the corrosion can also affect the gas burners and heat exchangers, making the heater less effective overall.

Keeping this issue in mind, the manufacturers design the heaters with various precautions against corrosion, such as a glass lining of the tanks and a pressure relief valve. Even though these two methods of resistance against corrosion are certainly helpful, the guaranteed way to extend the lifespan of your water heater is to install and regularly change an anode rod.

Long Vs Short Term

Anode rods are made of more reactive metal, which preferentially corrodes over the metal of the water heater tank. Their function relies on their inevitable deterioration, and their deterioration eliminates their function. Once fully corroded, the rod is useless and the tank will start to suffer the effects of corrosion. This makes replacement crucial.

If you regularly replace the anode rod, then you can even save money upfront by opting for the shorter warranty.

How Long Do Water Heaters Last Without Anode Rods?

It is difficult to estimate how long the water heater could last without or with an old and deteriorated anode rod. It depends on many factors, which we’ll further discuss later in this article. However, it is safe to say that an anode rod could double or even triple the number of years that the water heater can effectively function for. This will save you money in the long run and can spare you the trouble of dealing with rust-containing water.

To give you a better idea, a water heater without an anode rod can last anywhere from 3-8 years, depending on the conditions. A heater with an anode rod typically lasts between 10-15 years, as long as you change the rod regularly.

2. Prevent Bursting Water Tanks and Water Damage

Here we are beginning to touch on some of the more serious problems that corroded water tanks can cause you. If the water tank does not have an anode rod, it will eventually rust out, which often leads to pinholes that will cause water leaks, but in the worst case, the corrosion can get so bad that it will cause the tank to burst completely.

Putting aside the obvious safety risks that this would pose to any people or animals who were in the proximity of the water heater at the time, let’s look at other damages associated with the water tank bursting in your home.

dirty water heater

On top of needing to deal with having only cold water until you purchase and install a new water heater, the incident can cause some severe water damage. The most common results of water damage are ruined floorboards, stained ceilings, mold and mildew growth, or even flooding of your downstairs neighbors.

Needless to say, fixing all these issues can be very pricy and time-consuming. Thus, changing an anode rod every few years ends up being much better for your wallet as well as for your health and well-being.

3. Rust-Containing Water Is Not Healthy for People

Rusty water is not only undesirable due to its tendency to stain sinks, toilets, bathtubs, or freshly washed laundry, but because it downright poses a danger to your health.

The reason behind it is its high concentration of iron. Even though oxidized iron is an essential nutrient, the phrase “too much of a good thing” applies in this case as well. If you were to drink rust-containing water daily over a longer period of time, it could eventually lead to a condition known as iron overexposure or iron poisoning.

The first symptoms of iron poisoning are often nausea, abdominal pain, vomiting, dehydration, and diarrhea, but it could also be dizziness, low blood pressure, and a fast or weak pulse. This condition is quite serious, and it could cause organ failure if it is left untreated.

Problems with sewerage of private building. view of dirty water flowing from faucet

It is more likely to get iron poisoning from excessive amounts of iron supplements rather than getting it from water. Nonetheless, it is still possible, particularly if you are already on an iron supplement, and that should be reason enough to invest in anode rod replacements for the water heaters and in water filters.

Showering in rusty water is also not a good idea. Although it does not bear any inherent health risks, it could dry and damage your hair or cause clogged pores, rashes, and dry skin.

On top of that, there is the possibility that bacteria will begin to live in such water or that you will accidentally drink a large chunk of rust that may cut you.

4. Water Smells Like Rotten Eggs (Well Water)

If the water starts being smelly, it doesn’t necessarily mean you have a worn-out anode rod, you just may have the wrong type, and thus you need to change it.

The sacrificial anodes typically consist of metals such as magnesium, aluminum, and zinc. When the anode rod corrodes itself, these metals ionize in the heater leaving free electrons floating in the water. Sulfate-reducing bacteria can then use these electrons to create hydrogen sulfide gas that smells like rotten eggs.

While magnesium and aluminum rods allow bacteria to produce this gas, zinc anode rods produce ions that are toxic for this bacteria. Therefore, if your water is smelly, you can change the anode rod to a zinc or zinc alloy one that will be able to kill the bacteria and stop the production of hydrogen sulfide gas.

Alternatively, you can switch to a powered anode rod that does not contain magnesium or aluminum and thus will not produce the smell.

Smelly water associated with the anode rod in your water heater is more common for houses fed by well water. To learn more about rods for well water and how to tell whether anode rod is the cause behind smelly water, check out this article.

How Often Should You Replace an Anode Rod?

The precise time frame for changing the anode rod will differ from case to case. It is good to check the anode every once in a while to know how much of it dissolved over time.

Many manufacturers recommend checking the anode rod at least once per year and changing it when you see that more than 50% of it has been dissolved. Generally, this occurs every 2-5 years.

How long a certain anode lasts always depends on these four factors:

  • The hardness of the water – mineral build-ups on the rod can interfere with its necessary corrosion.
  • The presence of a water softener – water softeners add sodium ions into the water. Sodium ions are highly corrosive, so if you have a water softener, you will need to change the anode more often.
  • The amount of water that goes through the heater – if you have a large family or you like to take long showers, the heater sees more use, and therefore, the anode rod deteriorates quicker.
  • The material the anode rod is made of – while magnesium does good in soft water, aluminum lasts well in hard water and water with a high PH.

Another option is a powdered anode rod that does not deplete at all. It is permanent because it uses electrical pulses rather than depleting itself to prevent corrosion. It is typically made of durable metal, such as titanium. State water heaters offer models that use powered anode rods.

Manufacturer instructions – the manufacturer knows their anode best. They have most likely performed many tests and have enough experience and customer feedback to give you the best advice about the maintenance of the anode rod.


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