How to Replace Your Water Heater Anode Rod in 2022
**Our honesty policy: This post may contain affiliate links and I may be compensated if you make a purchase at no extra cost to you. Some are, some aren't--I do some comparison shopping. The important thing is you will know exactly what we are talking about. Drop a note/comment if you have any questions on the products as these are materials and tools we use on our own projects.
A new versus an old water heater anode rod: the comparison of before and after water heater anode replacement.
Go you for researching how to replace your water heater anode rod! Maintenance on a water heater is one of those items that, in all honesty, generally doesn’t make the to do list. We all expect to have hot water in our houses and then one day a leak occurs or some other dire circumstances requiring a new water heater.
Of course, since you are here, you are one of those super homeowners who has emptied out the tank from time to time. Getting the settled grit and corrosion out of the bottom by emptying the tank is a manufacturer warranty item. The suggested frequency is once a year but every other year would still get you a gold star.
The even bigger maintenance item is replacing the sacrificial anode from every three to five years. Changing out this one rod extends the life of your water heater to almost double the average lifespan.
$30-$50 and a little elbow grease to keep yourself from buying an extra $700-$900 tank water heater?!?! Let’s get to it!
What is this thing–sacrificial anode–you speak of?
Oven overlooked and ignored, there is an extra little protrusion coming out of the top of your water heater.
This little hexagon shape is the top of the sacrificial anode rod.
An anode rod is some combination of aluminum, magnesium and zinc surround a steel core wire. Water heaters are designed to corrode this piece of metal extending down through the tank. Rather than corrosion building up on the outside of the steel tank it attacks the anode rod instead. Hence, the label “sacrificial”.
If the sacrificial anode rod is not replaced the water eats all the way through it and then starts corroding the tank. If it goes through the entire anode you are left with an iron will not be able to take it out and replace it. This shortens the lifespan of the water heater. Instead, you’ll just be replacing the anode, if not replacing the water heater.
It looks like we got this one just in time! While it’s not halfway through it certainly has some pretty gnarly at etch marks.
How to replace the sacrificial anode rod.
Water heaters generally come with a solid sacrificial anode. Being that they are generally about the same the height of the water heater you’re looking at something three or four feet long.
How to replace it seems easy enough:
- Buy a new one
- Turn off the circuit to the water heater (I didn’t trust just turning off unit at the electrical box right by it)
- Drain out some of the water after letting it cool off a few hours (it’s still hot so watch out!)
- Take the old one out
- Replace it with the new one
Sounds easy, right?
However, there are a few factors leading to a much more complicated project:
- Is the old anode solid or segmented?
- The height of your water heater.
- The height of your ceiling.
- Is it on a stand?
- The plumbing connections if it has to move.
- How far gone is the old anode?
Being that the water heater generally comes with a solid anode, you’re going to need some distance between the top of the water heater and the ceiling. If you don’t have much space you are going to have to move your water heater to a place where you have ample space.
Which leads to the next complication, how hard is it to disconnect the plumbing from the water heater if you have to move the water heater for servicing?
In our case, when we replaced the water heater along with our under slab plumbing leak, we placed it on a stand with sliders below each leg. We also attached the incoming cold line and the outgoing hotline with SharkBite connections.
You can see the SharkBite connectors here complete with the tags we never removed. It’ll be easy to see what we need to buy if we have to replace them later.
The setup above is a bit over complicated with the Sharkbite ball valve and then a separate SharkBite hose connector. You can buy a SharkBite water heater hose connector with the ball valve already integrated. You can check SharkBite water heater connectors out for yourself here.
This setup was designed with the intent to drain the tank and slide the unit out to the vaulted ceiling area for maintenance reasons. The water heater’s location is in an 8-foot height laundry room. Since the unit is so far off the ground and it is at least 4 feet in height, it would be impossible to take out original sacrificial anode rod in place.
Party on! Also not your normal location for a water heater…loving the balloons and puzzle pieces in the foreground.
The threads on the old anode might have some corrosion too so just be prepared to pull out your hammer drill.
Pulling out the hammer drill after the torque wrench didn’t work. You can also see the lower ceiling in the laundry / hot water heater room. Anode rod replacement was not going to happen here.
Just a little buildup to make it a PITA to remove with a breaker bar…
Help the new sacrificial anode rod seal up with a few rounds of teflon tape.
How do you know what to replace it with?
An aluminum / zinc rod lasts longer than magnesium, but magnesium protects your tank better.
Our limited experience and limited time with this fix led us to a segmented magnesium anode (here is the link to the exact one). We also liked it because it was pretty much all inclusive with the oversize socket. As you can see in the picture above, the anode rod is recessed into the top of the tank below the metal.
We were not able to find the size in the paraphernalia that came with our water heater or on the manufacturer website. With four segments, if it was too long we could cut one off.
When we first placed the replacement anode in the tank it hit the bottom. They not supposed to touch the bottom–avoiding another point of corrosion on the tank itself.
The anode touched the bottom of our tank on the first try. We made short work of the bottom segment with a grinder. You can also use bolt cutters or a hacksaw to make a clean cut in the connecting cable.
Water heater sacrificial anode rods: solid versus segmented
If you have time on your side, a better solution is to remove the old one, measure it, and then put it back in. While it might seem like a exercise in frustration–ours wanted to cross thread–on the positive side, you’ve just had a practice run. And even better, don’t have to guess what you need. Or you might get lucky and find out your anode rod is just fine and you don’t have to replace it yet.
The good thing about a solid rod is there is more surface area for the water to corrode. The bad part, again, is the amount of space needed above the water heater and grinding through the anode if you need it to be shorter. A segmented rod is much easier to clip off and put in.
We’ll see how well the segmented anode rod performs in a few years and report back to you here.
Materials needed for water heater anode replacement
If you don’t have this, these will make the next replacement easier
SharkBite water heater connectors
Tools needed
5 gallon bucket(s) to drain out the tank
Water hose — to drain out the tank
Grungy old towels — to clean up what escapes from both draining the tank and definitely what comes out of the pipes if you have to disconnect and move the tank
Hammer drill — to remove the old anode rod
1-1/16″ 6 point deep-well socket (may come with replacement anode if you get a kit)
1/2″ ratchet or breaker bar — to put back the new anode nicely
You: What’s the big deal? Mine just looks like a steel core wire.
Yeah, that sucks.
It’s too far gone. The water ate through the magnesium, aluminum and zinc.
Even if you have mad Operation skilz (remember that game?), this is out of your ballpark.
Draining what you can out and replacing it with a new anode rod is your best option. It can still extend what life you have left in this water heater.
Don’t forget to celebrate once you are done!
Spending $30-$50 instead of a huge amount on a new water heater is just cause for celebration!!!
Grab a beer and a fancypants donut if those are your vices.*
I’d suggest an Achocolypse from Prescott Brewing Company and M&M Hurts Donut.
Whatever your vice, reward yourself!
How do you prevent this from happening again?
First off, congrats! Knowledge is power and now you know after reading this blog post.
One suggestion is to set up a Google Calendar notice when you install you’re next water heater and then also after your next water heater anode replacement.
Hi Margaret,
You’re going to like this (I think).
Our water heater is the original one installed in our house that was built in 1985. So that means that it is 34 years old.
It shows NO leaks or other problems.
Hard to believe that an anode would last that long (I had no clue that a water heater had an anode or that it was used sacrificially to extend the life of the water heater casing), but apparently it has.
Austin, where we live, does have some of the purest, least-treated municipal water in the entire country, so maybe that has something to do with its long life?
So, here’s my question: given the life of our water heater, would you recommend that we replace the anode?
Nice!
Why change a good thing?
Maybe it could have lasted 68 years! 😉
In all seriousness, I would. How has the water looked when you drain the tank? That would be a gnarly anode picture if/when you remove it!