Hot water heater anode difficult to install

[astrocaster]

Back in November, I removed the hot water heater (HWH) anode to drain the heater in preparation to winterize our Oliver. The anode which I removed is the original one and is partially corroded, as expected, yet it appears that it could be used for a few more camping trips, before needing replacement. I have also purchased a replacement anode--the CamcoRV "RV Water Heater 9 1/2" Anode Rod," which the packaging says is an "aluminum 3/4" MPT for Morflo/Suburban Water Heaters." It is CamcoRV's product number 11563. From all that I have seen on this and other boards and on vendors' websites, this is one of the standard replacement rods for the Suburban HWH.

 

The problem I am having is that I cannot screw it all of the way into the HWH. It binds up and will not turn further than about six revolutions; there are about four more revolutions of thread at the head of the rod remaining at this point. It also leaves about four revolutions of threading on the HWH itself to go, before the rod would be totally screwed into the HWH. Interestingly, I have discovered the same problem in trying to screw the original anode rod back into the HWH. However, since the original rod has four fewer turns of threading than the replacement rod, it does come closer to being totally screwed back into the HWH. I would need to get it about 1 1/2 revolutions further into the HWH to have it fully screwed in.

 

Before attempting to screw either of these rods into the HWH, I carefully removed with vinegar some white deposits that had formed on the threads of the HWH that were closest to the tank. These had been exposed to the water in the tank during its use, since the OEM rod's threads did not extend far enough to cover them. Then, I carefully traced the groove of the threading from beginning to end in the HWH with a pick/stylus, removing any remaining deposits. Thus, by both visual and physical examination, the threads of the HWH appear to be in very good condition. Still, neither anode rod can be fully screwed in.

 

I have tried several methods to screw the rods in: using Teflon pipe tape, using plumber's lubricant, even chilling the rod in order to take advantage of potential expansion/ contraction differential. I have the appropriate socket and a very long breaker bar, and I am applying so much torque that I would be concerned about breaking something if I applied more.

 

I have read all the posts I could find on this forum and two others discussing replacing the HWH anodes, and I have been mindful of all of the tips and pointers I have seen. I have particularly attentive to not cross thread the rod when inserting it into the HWH. In fact, the rods both turn very easily and have just the expected amount of play in them through all six turns, until they cannot be turned further.

 

So, with this background, I would appreciate any advice you could offer. In particular:

 

(1) Have you experienced a similar problem and how did you solve it?

 

(2) I believe that if I screwed either of these rods in as far as I have been able to--about six revolutions--after applying teflon tape or other gap sealer, there might not be any leak. Is it absolutely necessary for the anode to be screwed all the way into the HWH to perform its function, if it is screwed in enough not to leak?

 

(3) This fitting seems similar to what I have experienced in some pipe fittings, where the diameter of the fitting actually narrows, as is the case with tapered thread pipe threading. Is this fitting actually tapered? It certainly seems like it might be.

 

Thank you very much, in advance, for your advice!

 

Steve

[mountainborn]

Steve, We recently replaced our anode, getting ready for the Spring Campout and Jug Fishing Extravaganza at Lake Greeson.

All of your observations are correct:

The anode only needs to be there, suspended in the tank's water, to do it's job.

The threads are tapered so that they will "swedge fit" tightly.

Teflon tape or "pipe dope" facilitate sealing so far as no leak is concerned, but keep the threads from seizing up, making the next change out of the anode easier.

Looks like you "gotter' done" !

Just check to verify that there is no leak when you fill the water system and you are "ready to roll' !

[ScubaRx]

Steve,

 

I'll echo mountainborn there. I just replaced mine a couple of days ago (I had taken it out back last fall to drain the tank.) I found that it would only screw in about half way. I had put teflon tape on the threads. I read/heard somewhere not to put teflon tape all the way to the end of the threads, something about excess inside the tank possibly getting loose and perhaps fouling a pump. Don't know how important that is but I can see where it makes sense. Bottom line on installation...if it doesn't leak, it's OK.

 

Steve

[astrocaster]

Larry and Steve,

 

Thank you for your helpful responses. I will consider it sufficient to get the anode screwed in well enough to be securely seated and not leak, even if it is not screwed all the way in. I'll be careful regarding any excess teflon tape, too.

 

Steve