What is the purpose of the sacrificial anode in a water heater?

The purpose of the sacrificial anode in a water heater is to prevent tank corrosion. This is a critical function as water heaters are typically made of metal, which is prone to rust and deterioration, particularly when in contact with water. The sacrificial anode is typically made of a more reactive metal, like magnesium or aluminum. During the electrochemical process of corrosion, the anode will corrode preferentially over the metal of the tank itself. This protective mechanism extends the life of the tank by reducing the rate at which it deteriorates.

In the context of water heaters, prioritizing the prevention of corrosion is vital due to the harsh conditions created by the combination of heat and moisture. Regular maintenance, including checking the condition of the sacrificial anode and replacing it when necessary, can significantly enhance the longevity and effectiveness of the water heater.