Why You Need a 6-Point Socket to Remove a Water Heater Anode Rod

Anode rod head with sockets
Anode rod head with sockets

As mentioned there, removing a water heater anode rod generally requires considerable, umm, persuasion. I used a 12-point socket wrench, as I didn’t have a 1-1/16″ impact wrench on hand. Now I do…

The first pic shows the head in front of the two sockets; the 6-point socket on the right will do a much better job of not ruining the anode rod bolt head because it grips along the entire length of all six sides.

Now, in general, you don’t care about ruining the head, because the rod’s pretty much not going to be there by the time you remember to check it. What you do not want: the wrench rips the corners off the head before loosening the thread.

Goobered anode rod head
Goobered anode rod head
Goobered anode rod head - side view
Goobered anode rod head - side view

The thread on this anode rod was in great shape (I’d wrapped it in Teflon tape the last time it was out), but it was still firmly jammed in place. These pix show what the 12-point socket did to the bolt head during the beatdown.

Bottom line: right now, while you’re thinking about it, buy yourself the nice 6-point 1-1/16-inch impact socket you’ll need to extract the anode rod from your water heater. If you don’t already have a honkin’ big breaker bar, get one of those, too; this is no job for a sissy 3/4″-drive ratchet wrench.

The real problem is holding the water heater in place while you beat on the breaker bar. I have yet to see a good solution.

Offset Tank - 2009
Offset Tank - 2009

That husky 6-point socket isn’t going to fit into the stupidly offset hole in the top of the water heater, even after applying the nibbling tool to get the 12-point socket in place, but that’s in the nature of fine tuning…

12 thoughts on “Why You Need a 6-Point Socket to Remove a Water Heater Anode Rod

    1. Believe it or not, it’s a mere 1.0625 inch across the flats.

      Now, this being a plumbing project, I’m absolutely certain that there are enough standards to go around: some manufacturer uses a 1-11/16 inch anode rod head…

      1. sissy 3/4 perhaps 3/8ths? a decent 1/2″ should do it

        if you rap the anode with teflon how do you maintain electrical continuity with the tank to allow the anode to work? the anode doesn’t look that wasted. Perhaps it’s not working correctly and your tank is rotting out-hence sediment

        great blog, most of it’s way above my head but interesting nuggetts in there

        1. sissy 3/4 perhaps 3/8ths? a decent 1/2″ should do it

          I wish that were true, but the length of the breaker bar varies with the drive stud. You (well, I) need the bigger stud to get enough lever arm to apply enough torque to break the [mumble] thing loose.

          if you [w]rap the anode with teflon how do you maintain electrical continuity

          No magic: the threads cut through the tape here and there to produce a metallic joint between the bolt and the tank. What the tape does do is lubricate most of the thread surface and prevent corrosion so you can get the bolt back out again.

          the anode doesn’t look that wasted.

          Mmm, that little rusted stub is what’s left of the steel wire cast inside a four-foot long, half-inch diameter aluminum rod: nothing!

          The fact that the threads weren’t corroded in place was basically a bonus, but the rest of the rod had done its duty.

  1. Greetings from Dauphin, Pa

    Very interesting reading – extremely valuable information! Very charitable on your part.
    Thought I’d offer some theories I have on Water heaters.

    Removing the ANODE Rod:
    Yes, checking it at an interval BEFORE it rots too much is a good idea AND investing in the tool an absolute must – as is stated in the information already provided here.
    Since it does require the strength of ‘the terminator’ to remove the anode rod – the tank can move around causing grief…I suggest removing app. 10% of the water, the weight of the remaining water should help hold the tank in place until you loosen the nut atop the tank. Once loosened you can then drain the tank – remove the rod.

    Many Folks complain of short life of their tanks. And about excessive ‘sediment’ accumulating within the tank.
    My tank, after 12 years, seems to be in very good condition. When I flush it – I get only a trace of what looks like sand in the bottom of the bucket otherwise the water runs clear.

    I have concluded this to be as a result of the previous owner having the water entering the heater tank FIRST pass through a whole house filter and then a water softener.

    Curious…do You have your water system set up this way?

    1. pass through a whole house filter and then a water softener

      That’s the setup: a legacy of the original well that definitely needed sediment filtering. I’ve read that softened water is hard on water heaters, but so is hard water; your water must come from the Goldilocks Zone.

      It’s getting to be time to check that rod, although I’m waiting for a nice, warm, dry day to run the hose out the basement door. March doesn’t provide many such days, so I’m hoping for April… and I’ll try leaving most of the water in the tank this time. Thanks for the suggestion!

  2. BTW, an impact driver, either electric, pneumatic or hammer driven may be of benefit to you.

    1. an impact driver … may be of benefit to you

      The thing allegedly has a glass-lined tank, which probably wouldn’t benefit in the least from the liberal application of an impact wrench… [grin]

Comments are closed.