Anode Rod Replacement: The $40 Part That Saves Your Tank

What the anode rod does

Inside every tank water heater is a rod of magnesium, aluminum, or zinc-aluminum alloy. It corrodes on purpose so the steel tank doesn't. 'Sacrificial anode' is the right term. Once it's gone, the tank itself starts corroding from the inside.

How fast it's consumed in Albuquerque

ABQ's hard water eats anode rods roughly twice as fast as soft-water markets. Magnesium rods that should last 5 years are usually toast at 2 to 3. Aluminum rods stretch to 3 to 4 years. Powered (impressed-current) rods last the life of the tank but cost $185 to $285 installed.

When to check it

Year 2 if you have a magnesium rod and ABQ tap water. Year 4 if you have aluminum. Anytime if the hot water smells like rotten eggs (sulfur reaction with a magnesium rod — switch to aluminum or zinc-aluminum).

DIY or call us

It's a 30-minute job if everything cooperates. The catch: the hex head is torqued to 50+ ft-lbs, the rod is 44 inches long, and ABQ's hard water often seizes the threads with calcium. If you don't have a 1-1/16-inch deep socket, an impact wrench, and ceiling clearance, call us. $185 to $285 installed beats stripping the hex head and damaging the tank.

How we replace it

• Shut off gas/power and cold water supply
• Drain a few gallons from the tank to drop the water level below the anode port
• Break the hex head loose with an impact wrench
• Inspect the old rod (a rod consumed below 1/2 inch diameter or down to the steel core needs replacement)
• Install a new rod with Teflon tape or pipe dope on the threads
• Refill, restart, check for leaks