Tank-style water heaters consist of more than just a tank and heating element. They contain several other parts, including an anode rod. If your home is equipped with a tank-style water heater, it probably has an anode rod. The anode rod is an important part of nearly all tank-style water heaters.
What Is an Anode Rod?
An anode rod is a long rod-shaped part. It typically features a steel core that’s covered in either magnesium, zinc or aluminum.
You won’t be able to see the anode rod when inspecting your water heater. It’s found inside of the tank’s interior. To see the anode rod, you’ll have to drain and open up the tank. Because it’s concealed, many homeowners are unaware of the anode rod.
Why Tank-Style Water Heaters Need an Anode Rod
Tank-style water heaters need an anode rod to protect the tank’s interior against corrosion. The anode rod works by attracting iron, iron oxide, limestone and other contaminants. By doing so, the anode rod will protect the tank’s interior against corrosion.
Corrosion can cause serious damage to tank-style water heaters. It will eat through the metal from which the tank is made. If the tank is completely corroded, it may fail to hold pressurize. The anode rod prevents this from happening by attracting rust-causing contaminants in the water.
Anode rods attract rust-causing contaminants through a chemical process known as electrolysis. They will pull rust-causing contaminants out of the water. As the contaminants land on the anode rod, the anode rod will begin to corrode. Anode rods are sacrificial in this regard. They sacrifice themselves so that the tank’s interior will remain protected against corrosion.
What About Tankless Water Heaters?
While commonly found in tank-style water heaters, tankless water heaters don’t need an anode rod. Anode rods are designed specifically to protect the tank’s interior against corrosion. Tankless water heaters don’t have a tank, so they don’t need an anode rod.
If you have a tank-style water heater, you may need to replace the anode rod. Anode rods will corrode. After about three to five years, they may be completely corroded to the point where they no longer protect the tank’s interior from corrosion.
Of course, another option is to upgrade to a tankless water heater. Anode rods are exclusive to tank-style water heaters. By upgrading to a tankless water heater, you won’t have to worry about replacing the anode rod.