There’s probably nothing more upsetting to find on a water heater than rust or other forms of corrosion. Because water heaters have water and metal in constant contact, the development of corrosion seems like something that should naturally occur. But yet it rarely does… until the water heater is at an advanced age. When people spot a corroded water heater, they often think that it must be replaced. Is there any truth to this?
Most of the time, yes, the water heater should be replaced
Storage tank water heaters are specially designed to resist corrosion for as long as possible. The principle defense is a device called an anode rod, a.k.a. sacrificial anode rod. This rod made of two different types of metal is attached to the top of the hot water tank and extends down through the water. The rod attracts corrosion to it and away from the tank—“sacrificing” it to prevent the rust from affecting the other metal in the water heater. But the rod must be regularly replaced as part of maintenance or else corrosion will take hold.
If corrosion appears on only a few parts of the water heater, such as the heat exchanger, it’s sometimes possible for repair technicians to replace the affected sections without having to replace the entire water heater. Make sure to call for professional assistance as soon as you detect the corrosion so they can attempt to save the water heater.
However, when corrosion is advanced it is already weakening the tank. If the tank corrodes to the point where it’s starting to contaminate the water supply, then the best choice is to have the whole system replaced. However, take this opportunity to have a more advanced type of water heater installed, like a tankless or a heat pump water heater.
Malek Heating & Cooling has served Winnetka, IL and all of the Chicagoland area since 1998.