As professional plumbers who work on everything from small leaks in homes to large scale commercial plumbing installations, we’re used to encountering one of the biggest enemies of all plumbing systems: corrosion. Corrosion is a chemical reaction between water and metal in the presence of oxygen, resulting in a weakening of the metal. There are different types of corrosion, but rust is the most familiar. No matter the type, corrosion is straight up bad news for metal because it eats into it and eventually causes it to flake away. (In fact, the word corrosion comes from the Latin word meaning “to gnaw.” Corrosion gnaws away at metal.)
The tank water heater in your home is an appliance that is in danger of corrosion because of the contact between metal and water. But, you’ve probably noticed, the water heater is quite resistant to corrosion. That’s because models are designed this way, with a number of safeguards to stop the tank or other components from beginning to rust.