Steel rusts and corrodes when exposed to water for extended periods of time. This, along with the acidity of water, leaves water heaters vulnerable to a more rapid corrosion process and bad smelling water.
By installing an anode rod you can delay this process and extend the life of your water heater. Usually made from magnesium, the rod, succumbs to corrosion before other components of the water heater will. It then delivers electrons into the tank, creating an environment that prevents corrosion of the tank and its elements. But once it’s corroded, the anode rod needs to be replaced to continue its protection.
Anode rods come in two varieties: ones with a hex head and ones with a nipple that goes on the hot water outlet.
There are three options for material: aluminum, magnesium and zinc aluminum. Zinc aluminum is for water sources with sulfur, a.k.a. “Smelly water.” Aluminum and magnesium are interchangeable depending on the brand.
The hole is same size on all heaters, but some rods are longer or thicker. Go off the model and serial number to ensure a proper fit.
If there is limited space above the heater that prevents the installation of a standard anode rod, you can purchase and install a flexible anode rod.
1) Turn off water and fuel supply (gas or electricity) to water heater.
2) Drain around 6 inches of water to give you access while keeping weight in the tank.
3) Locate the anode rod on the water heater; if necessary, unscrew and lift off the cover from the top of the heater.
4) Use a ratchet wrench with a 1 and 1/16-inch deep socket to unscrew the anode rod from the heater. If it is the nipple type, you will need an adjustable wrench.
5) If the anode rod won’t budge, slip a steel pipe onto ratchet wrench handle for extra leverage.
6) Lift out and discard the old anode rod.
7) Wrap Teflon tape around threads of new anode rod and insert the anode rod into water heater and tighten with the 1 and 1/16-inch socket.
8) Turn the water and fuel supply to the water heater back on.
Watch the video below to see how it’s done.