Want to get the longest possible life out of your water heater? Then you have to change your anode rod. If you don’t know what an anode rod is or how to change it, plumbing and heating expert Richard Trethewey is here to guide you.
What Is an Anode Rod?
An anode rod is a long metal rod typically made of magnesium, aluminum, and/or zinc. It’s inserted into the water heater tank to attract corrosive elements in the water that would otherwise attack the steel tank.
Why Is It Important?
The anode’s rod primary function is to extend the life of your water heater. Water naturally wants to attack steel. The anode rod, made of a less noble metal, becomes the primary target for this corrosion and, in effect, protects the tank.
But once the rod is fully corroded and there’s nothing left, the water will start corroding the steel tank. As a second layer of defense, most water tanks have an interior glass lining, but the glass can have small areas of imperfections that can crack and expose the steel.
When to Replace the Anode Rod
Typically, you should inspect your anode rod every three to five years and replace it when it’s significantly corroded.
If more than 6 inches of the core wire is visible or the rod is less than ½ inch thick, it’s time to replace it.
How to Replace the Anode Rod
Locate the Anode Rod
Look for the anode rod on top of the water heater. In some models, you may need to remove a cover to access it. The anode rod typically has a hexagonal head.
Turn Off Water Heater
Shut off the fuel supply (gas or electricity) to the water heater. For gas, the shut-off valve is typically on the gas line near the bottom of the water heater. For electric, shut off the power at the breaker in the electrical panel.
Turn off the water supply to the water heater. The valve is usually on the cold water line above the tank.
Allow the tank to cool before proceeding.
Partially Drain the Tank
Connect a hose to the drain valve at the bottom of the tank.
Place the other end of the hose in a utility bucket or drain to catch water.
Turn on a hot water faucet somewhere in the house. This will relieve pressure in the plumbing system and allow water to drain more quickly. If the water continues to flow normally from the faucet, the water wasn’t shutoff all the way. Tighten the tank’s water shutoff valve.
Open the drain valve. Use caution as water may still be hot. Some drain valves need to be opened with a flathead screwdriver, a key, or by simply turning a lever.
Drain about 10-15% of water from the tank. Roughly a few gallons. This will prevent water from spilling out when the rod is removed. But by leaving the tank mostly full, the weight will stop the tank from spinning when removing the rod.
Remove the Anode Rod
If your anode rod is newer, it may not take as much force to get out. It’s still a good idea to have a second person ready with towels to clean water spills and to hold the tank in place.
Most water heaters use an anode rod that will fit a 1-1/16” socket. A 12-point socket is more likely to slip and round off corners of the anode’s hex head, so 6-point socket is better to use.
Try loosening the hex head using a socket wrench or breaker bar. A socket wrench is smaller and can be simpler to use if the anode rod isn’t stubborn. Breaker bars are longer, non-ratcheting tools that provide more torque because of their length, making it easier to remove the rod. Or to add extra leverage to a socket wrench, use a metal pipe as a “cheater bar” to add as an extension over the socket wrench.
If it’s still not budging, wrap a heavy-duty ratchet strap around the water heater. Have the second person use the ratchet strap as a handle to hold the tank in place while you loosen the anode rod.
Removing an Extra Stubborn Anode Rod
If hand tools can’t remove the anode rod, a power impact wrench can loosen stubborn anode rods.
Use an impact wrench with an impact-rated 1-1/16” 6-point deep socket to remove the anode rod.
Once loose, carefully remove what’s left of the old anode rod.
Install New Anode Rod
Most tanks don’t have enough ceiling clearance for a standard, straight anode rod to be installed. A flexible anode rod is best for water heaters in locations with low ceilings.
Wrap several layers of Teflon tape around the threads of the anode rod.
Insert the anode rod into the tank. For flexible rods, carefully bend what’s needed to get the rod into place. Straighten it out as it goes in so it will hang straight down.
Tighten the hex head into place with a socket wrench.
If there was a cover over the anode rod, do not add back until you have checked for leaks.
Refill and Restart
Close the drain valve and remove the garden hose. Turn the water supply to the water heater back on and allow the tank to refill.
After a minute or so, shut off the open hot water faucet that was turned on at the beginning of the process. Once the water is flowing steadily.
Check for leaks
Inspect the area around the new anode rod for any signs of leakage. Tighten the rod further if you notice any drips or reapply Teflon tape.
Restore Power
Once you are confident there are no leaks, restore the fuel supply to the water heater. For electric heaters, switch the circuit breaker back on. For gas heaters, relight the pilot light following the manufacturer’s instructions.
Maintaining Your Water Heater
Regular maintenance can significantly extend the life of your water heater and improve its efficiency.
Regular Inspections
Check the anode rod annually, especially in areas with hard water. Inspect for signs of rust or sediment buildup in the tank. Test the pressure relief valve periodically to ensure proper function.
Flushing the Tank
Drain and flush your water heater tank annually to remove sediment. This process can improve heating efficiency and extend the life of your appliance.
Professional Maintenance
Consider having a professional plumber inspect your water heater every few years. They can perform more thorough maintenance and catch potential issues early.
Changing the Anode Rod in Water Heater: Our Conclusion
Changing your water heater’s anode rod is a simple yet effective way to extend its lifespan. While it may require some effort, especially in tight spaces, the benefits far outweigh the inconvenience. Regular maintenance, including timely anode rod replacement, can save you money and ensure a reliable hot water supply.
