Water heater has kidney stones

[whoot]

I pulled out the old anode from the water heater, and washed out a bunch of weird white rocks. Then I got a water heater flusher, and washed out a bunch of more weird white rocks. Then I pressurized the water system with the old anode back in, forgot I had removed the kitchen faucet, and flooded the Casita. Then I washes out some more weird white rocks.


Then I re-pressurized the water system, towed the Casita across a field to bounce it around, then washed a bunch of more weird white rocks. I did that two more times.


How much crap can be in a 6 gallon water heater? There doesn't seem to be any end to the weird white rocks that keep coming out of it.


I have a brand new magnesium anode with tape on it, ready to screw in, but now I am trying to get the white stuff out before I put in the new anode: "ONENESS 369 (2 Pack) Suburban RV Anode Rod Replacement Part 232767 - Magnesium - 9.25" L - 3/4" NPT Thread with PTFE Thread Seal Teflon Tape"

[Paul O.]

What an adventure!


My water heater has the nylon plug only (no anode) and one time I forgot that the system was pressurized and unscrewed the plug to drain it. I was also quite impressed by how much white stuff shot out, although it was pretty much sand like mineral stuff, no "rocks". By accident I found out how to really clean out the inside of the heater. Maybe that is what you want to do before you replace the anode. Good luck.

[AC0GV]

Originally Posted by Paul O.

What an adventure!


My water heater has the nylon plug only (no anode) and one time I forgot that the system was pressurized and unscrewed the plug to drain it. I was also quite impressed by how much white stuff shot out, although it was pretty much sand like mineral stuff, no "rocks". By accident I found out how to really clean out the inside of the heater. Maybe that is what you want to do before you replace the anode. Good luck.

I've been told that Scamps do not need them but I use one, it was only 5$.
Note that the rod needs to be made of the correct metal to do any good.

[rubicon327]

Originally Posted by AC0GV

I've been told that Scamps do not need them but I use one, it was only 5$.
Note that the rod needs to be made of the correct metal to do any good.

Last I knew Scamp uses Atwood water heaters with an aluminum tank which is why you don’t need an anode. The porcelain-lined steel tank on Suburban water heaters need an anode to prolong the life of the tank.

[Paul O.]

Originally Posted by rubicon327

Last I knew Scamp uses Atwood water heaters with an aluminum tank which is why you don’t need an anode. The porcelain-lined steel tank on Suburban water heaters need an anode to prolong the life of the tank.

I did not know that. Thanks for the info. My Scamp came with the nylon plug only from the factory (not directly to me, though).

[steve dunham]

Whoot , Do you have the dual fuel water heater
( Propane / Electric) ?
If so , I would remove the electric heating element and clean it (Soak in Lime Away or other calcium remover )
We flush our WH tank ,clean the electric heater element and replace the anode on a yearly basis —- A lot less expensive & less work than replacing the Water
heater .

[whoot]

Originally Posted by steve dunham

Whoot , Do you have the dual fuel water heater
( Propane / Electric) ?
If so , I would remove the electric heating element and clean it (Soak in Lime Away or other calcium remover )
We flush our WH tank ,clean the electric heater element and replace the anode on a yearly basis —- A lot less expensive & less work than replacing the Water
heater .

I think I do, it can run on propane or electric. I used electric for the first 6 months I had it, then switched to propane for 2 years. Is the anode the heating element?

[steve dunham]

Originally Posted by whoot

I think I do, it can run on propane or electric. I used electric for the first 6 months I had it, then switched to propane for 2 years. Is the anode the heating element?

No , the anode and the electric heating element are two separate items.
To remove the electric element you will need an 1 1/2” socket ( If I remember correctly) and you may need to remove the propane burner assembly to access the element

[Mike_L]

Those weird white stones are likely a calcium salt, probably calcium carbonate. This mineral occurs naturally in many water sources. Water also contains dissolved carbon dioxide which produces carbonic acid. The carbonic acid lowers the ph of the water and keeps these metallic salts in solution. As the water sits in your plumbing system it warms up and some of the dissolved carbon dioxide off gasses reducing the concentration of carbonic acid present. As the acid concentration drops the minerals begins to precipitate on surfaces and form these stones. Any water that evaporates from your system will leave the dissolved mineral content behind.
Calcium carbonate isn't toxic but can build up to clog your plumbing. An anode is used to collect these salts so they don't precipitate throughout your plumbing. Some trailer plumbing systems come with an anode already installed. Others come with a plastic plug which can be replaced with an anode.
The most effective way to remove these salts from your system is to use an acid to dissolve them. Any of a number of these acids will work. I suggest vinegar (5% acetic acid) as any residue left behind won't be toxic and can easily be detected by taste. Mix the vinegar 50/50 with water and fill your tank. Let it sit over night and drain. Repeat as necessary. The vinegar should make the stones foam as they dissolve so you know its working. You can use a stronger acid like phosphoric, found in products like CLR etc. (an ingredient of some colas) which works faster but you will need to flush you system well to remove residue. Running some vinegar solution through your plumbing will help remove any dissolved salts here as well. After you have descaled your system, install an anode and check it regularly to prevent future weird stones.

[whoot]

Originally Posted by Mike_L

Those weird white stones are likely a calcium salt, probably calcium carbonate. This mineral occurs naturally in many water sources. Water also contains dissolved carbon dioxide which produces carbonic acid. The carbonic acid lowers the ph of the water and keeps these metallic salts in solution. As the water sits in your plumbing system it warms up and some of the dissolved carbon dioxide off gasses reducing the concentration of carbonic acid present. As the acid concentration drops the minerals begins to precipitate on surfaces and form these stones. Any water that evaporates from your system will leave the dissolved mineral content behind.
Calcium carbonate isn't toxic but can build up to clog your plumbing. An anode is used to collect these salts so they don't precipitate throughout your plumbing. Some trailer plumbing systems come with an anode already installed. Others come with a plastic plug which can be replaced with an anode.
The most effective way to remove these salts from your system is to use an acid to dissolve them. Any of a number of these acids will work. I suggest vinegar (5% acetic acid) as any residue left behind won't be toxic and can easily be detected by taste. Mix the vinegar 50/50 with water and fill your tank. Let it sit over night and drain. Repeat as necessary. The vinegar should make the stones foam as they dissolve so you know its working. You can use a stronger acid like phosphoric, found in products like CLR etc. (an ingredient of some colas) which works faster but you will need to flush you system well to remove residue. Running some vinegar solution through your plumbing will help remove any dissolved salts here as well. After you have descaled your system, install an anode and check it regularly to prevent future weird stones.

It looked like I washed out all the rocks, so I put in the new anode (with tape on it), and made sure it did not leak. Should I remove the anode and tape I just installed, or would it be ok to wait a year, and do it next year?


If the tank is usable, I could wash it out next time. Or I can do it now, I would just have to re-tape the anode.



I noticed an occasional flake of dark-blue enamel getting washed out, I guess that is from some kind of tank lining.


Some of the junk that came out:

[Mike_L]

It does indeed look like you washed out a lot of rocks, but did you get them all or even most of them. I've seen 1/2 inch copper pipe completely blocked by the accumulation of this stuff on the inside over a number of years. As it accumulates it blocks off water lines. As it dislodges from surfaces it can block lines, damage tap seats, toilet flush mechanisms etc. Accumulation of these salts inside hot water tanks, humidifiers etc. is a major cause of their failure.
You have a small system and maintenance should be enough. Considering the amount of debris in your photo it looks like you had a fair amount of precipitation which likely accumulated over time. If your heater is working and you have sufficient water flow you should be good to keep using it. The new anode should reduce the amount of salt dissolved in the water going forward. Accumulations inside the system may continue to shed. Fill a large glass with water and see if any sediment settles to the bottom. When you turn on a tap, notice if the action feels gritty.
If the problems persist you may have to flush again and fill your system with the vinegar/water solution and let it sit over night. Cheers!

[Paul O.]

It is hard to tell from the picture if those bluish bits are pieces of enamel, or just more of the mineral stuff. The anode is made of a metal that is more reactive (electro-chemistry is in play here) than the other parts of the heater. The anode is what corrodes before the other parts, hence it is also sometimes called "sacrificial anode". I would look really close, maybe with a magnifying lens, to figure if those bits are really enamel, or just more of the mineral residue. I would use the heater until I could be certain it needs to be replaced. If it started leaking, I would attempt to patch it with Plumber's Epoxy Putty, or turn the water to it off and drain it if necessary. Continue on my camping trip and then fix properly or replace it when home. YMMV, of course.

[Donna D.]

White 'rocks' are normal, it's part of the sacrificial anode doing its job. Better to replace the anode, when needed, than the entire water heater.

[canyon Rafter]

Shortly after I bought my Fiber Stream my water heater began to leak! I pulled out the anode stick and there was nothing left so it is hard to say how long that water heater had been used before I got the thing. When I pulled out the heater the tank was really in bad shape with many places that were paper thin. So now with the new water heater I check the anode quite often and replace when needed. I also flush out the heater once a year so depending on how much I have used it. This new heater has lasted for quite some time and I am happy about that because new units today are not the same price as when I bought the replacement for mine about 15 years ago.

[Conrad S.]

Paul O. and Donna D. are correct about the chemistry of the anode (speaking as a former chemistry professor). Its purpose is to preserve metal parts in the heater by preferentially corroding (oxidizing) before they do. Often made of magnesium, a very active metal. The magnesium gives up electrons, dissolving in the process, to the less active metal to keep it from corroding. Same reason that steel is galvanized. The pictures that Donna posted show this corrosion very clearly. The same thing happens in your home water heater. The anode has nothing to do with collecting calcium salts. The white precipitate is probably composed of some magnesium salts and, especially if you have hard water, calcium salts.

[Mike_L]

I've seen blue and green corrosion where copper components have been used.

[bigangelman]

You also need to be careful on how to deal the a in anode rod. Too much teflon and you defeat it purpose. The anode rod is there to corrode instead of the water heater. I would only put teflon near the end of the threads closer to the nut portion, this leaves enough metal to make contact.

[David Prast]

It is my understanding the purpose of the Anode Rod is to retard the electrolitic action that eats a hole in the water heater tank. It does not "soften" your water to prevent mineral deposits in the tank. With hard water, the mineral deposits accumulate on the electric heating element causing them to fail. it is not as much of a problem with gas fired water heaters. But eventually the mineral nuggets accumulate and cause issues. You are likely

using hard water at campgrounds so there is no prevention or cure for the problem. It is NOT an anode issue.

[Glenn Baglo]

Wrap the threads, not the anode, and don't use a lot or it will be hard to thread in. Wrap counter-clockwise so that it doesn't unwrap when you thread it. I fill a 1 1/16" socket with coins so that I can apply gentle pressure to nut.

[David Prast]

Originally Posted by bigangelman

You also need to be careful on how to deal the a in anode rod. Too much teflon and you defeat it purpose. The anode rod is there to corrode instead of the water heater. I would only put teflon near the end of the threads closer to the nut portion, this leaves enough metal to make contact.

Won't hurt but unnecessary. The pipe threads will cut through the Teflon tape but more importantly water is an electrical conductor.