Water Heater Anode Antifreeze White Flakes

[Susquatch]

Last Fall, I winterized my trailer per Flagstaff's instructions in my Owners Manual. When I removed the drain plug from my water heater (made by Surburban) to drain the heater tank, I noticed a small amount of erosion on the anode surface - nothing to get excited about. I replaced the plug and proceeded to fill the system with a quality brand of RV Anti-Freeze. No problems were encountered other than the amount needed! I had to make a second trip to the RV Place for more AntiFreeze.

This spring when I de-winterized my travel trailer and drained the antifreeze out of the system, I discovered a HUGE problem. All of the Aluminium on the anode was gone! Just the core wire remained. Even worse, the entire inside of my water heater was coated with a white deposit about a 1/16th of an inch thick. Some of it came out the drain hole. It looks almost exactly like corn flakes except the flakes are snow white!

I did a fairly thorough scan of the internet and found very very little that described this condition or what caused it. Only one other forum mentioned it and didn't describe a solution or the cause. Google was basically of no real help. However, in looking up an owners manual for my water heater n the Suburban Website, I did find a "Tips for Winterizing" FAQ that reads as follows:

"If your water heater plumbing system is equipped with a bypass kit, use it to close off the water heater. Drain the water heater completely and leave it closed off (out of the system) in the bypass position, particularly if you are introducing antifreeze into the plumbing system. Antifreeze can be very corrosive to the anode rod. The result will be accelerated deterioration of the rod and heavy sediment in the tank. If the plumbing system is not equipped with a bypass kit and you intend to winterize by adding antifreeze into the system, remove the anode rod (storing it for the winter) and replace it with a 3/4" drain plug."

Apparently, something in the antifreeze is corrosive to the anode which reacts with it very rapidly. In just one winter the entire anode is completely gone! My guess is that this reaction also reduces the effectiveness of the antifreeze and could result in a cracked water heater!

At the very least, I am worried that these white deposits will:

• plug up my water lines,
• and/or get into my drinking water,
• and/or reduce the efficiency of my water heater.

Next year, I will not add antifreeze to my water heater. I will bypass the heater and drain it totally. I will probably try to suck any water out of the bottom of the water tank below the drain plug with a shop vac and a small plastic hose.

I wish this issue was more broadly known, and I wish it had been mentioned in my Forest River Manual. I also wish it could be added to every list of winterizing instructions everywhere. Tall request, but the consequences are not nice!

Unfortunately, there is nothing anyplace that recommends how to remove the white deposits. I made a bent water nozzle from a piece of copper tubing and attached it to the end of my garden hose so I could squirt water into the tank in most directions. It seems to have gotten a large amount out as the grass beneath my trailer looks like Snow White dumped a whole bowl of Grumpy's white corn flakes there. But I am equally sure there is still lots in there.

Does anyone know how to remove all the white deposits from my hot water tank?

Hopefully this post will end up being indexed by Google and be more readily available to other RV owners or at the very least to other owners of Forest River Products.

Cheers!

[LadyWindrider]

Just venturing a guess here, never tried it, don't know, PROCEED AT YOUR OWN RISK.

Create a mixture of 5 gallons of water and 5 gallons of WHITE vinegar. Pour this in the fresh water tank, and use the pump to to fill the water heater. Let the mixture set in there a few hours, maybe up to a day, then drain and flush the the entire system.

Good Luck with whatever you try.

[flyrotor]

I would try to back flush it with copious amounts of regular water, to do this, hook up to your city water, make sure your bypass valves are open to fill your water heater, removed the anode and turn the water on, the water will flush through the water heater. When you are no longer getting sediment out of the water heater, then replace the anode and find your low point drains and drain it for a five minutes or so. If you can remove the aerator screens from your faucets do so and flush each valve for a few minutes, first from the hot water lines, then follow up with the cold water lines. When complete, drain all your water out of the lines again using the low point drains. Don't forget your shower handles too.

When it comes to winterizing there is a lot of info on this forum, many correct methods to use. Some use the antifreeze, several blow out the lines with compressed air (set your air compressor to max 40 psi in the lines) Everyone here on this forum recommends DO NOT use antifreeze in the water heater. Mostly because it takes 6 gallons, but you have proved another reason not to use the antifreeze in the WH.

Good luck

[Herk7769]

Yes, ditto. No antifreeze in heater.
Flush out with LOTS of water.
Do not use faucets until all the crud is gone from hot water tank.
If you do (did) be alert for reduced water pressure from clogged screens in fixtures.

New Anode of course.

[Susquatch]

Originally Posted by windrider

Just venturing a guess here, never tried it, don't know, PROCEED AT YOUR OWN RISK. Create a mixture of 5 gallons of water and 5 gallons of WHITE vinegar. Pour this in the fresh water tank, and use the pump to to fill the water heater. Let the mixture set in there a few hours, maybe up to a day, then drain and flush the the entire system.

Since there are a billion, almost two hundred, white corn flakes on the ground near my trailer, I will scoop some and put them in some vinegar to see what happens!

In the meantime, we need to head up north for a week and I have run out of time. We can live without hot water for a while so I have bypassed my heater for a few weeks. I've put about 2 gallons of water into the heater hoping it will slosh around and loosen up some more flakes during the drive. I'll try and finish the repair when I get home. I'll let you know what happens in a week or so.

Cheers!

[Susquatch]

Originally Posted by flyrotor

I would try to back flush it with copious amounts of regular water, .........low point drains. Don't forget your shower handles too.

Already done. That was actually my first move before even heading to the internet and this forum.

Originally Posted by flyrotor

When it comes to winterizing there is a lot of info on this forum, many correct methods to use. Some use the antifreeze, several blow out the lines with compressed air (set your air compressor to max 40 psi in the lines) Everyone here on this forum recommends DO NOT use antifreeze in the water heater. Mostly because it takes 6 gallons, but you have proved another reason not to use the antifreeze in the WH.

Yah, I read all that last year when I was winterizing. But I figured the cost of the anti-freeze was small potatoes compared to the downside of a ruptured hot water heater! Since the drain is not at the very bottom of the tank, there is no way to get all the water out. About 3/4 inch remains. I live in Canada. Winters are COOOOOOOLLLLLDDDDDD!

So I filled it with antifreeze in order to ensure the concentration was high enough, and the hell with the cost! Obviously, my "new reason" as you call it, would have stopped that foolishness had I known it. Hence my main reason for posting here! Humans are intelligent. At the very least we should all try to learn from each other's mistakes. I figure its my turn to be the source of some damn good education for others! LOL!!!

The real world is the toughest teacher because she gives the exam first and then the lesson.....

Cheers!!!!

[Susquatch]

Originally Posted by herk7769

Yes, ditto. No antifreeze in heater. Flush out with LOTS of water. Do not use faucets until all the crud is gone from hot water tank. If you do (did) be alert for reduced water pressure from clogged screens in fixtures.

The flakes and remaining debris from the anode are all quite heavy. Afterall, they are a molecule that contains zinc or aluminium or whatever is in the anode. They should all settle to the bottom of the tank as they come loose. I think the chances of getting any in the water lines is actually much less than I feared. Of course, one should never ignore Mr Murphy - if it can get in there, it will..... LOL!!!!

Originally Posted by herk7769

New Anode of course.

New anode already in hand but not yet installed. I'll run without it for a few weeks. Corrosion rates are accellerated by high temperatures (thats why many Canadians know that you should not park in a warm garage in the winter if road salt is used in your area). Since I will not be using the heater for at least two weeks, I think its pretty safe to run without the new anode. I just cut the wire off the old plug and am using it as a plain plug for the time being.

Cheers!!!!

[Herk7769]

Originally Posted by Susquatch

I just cut the wire off the old plug and am using it as a plain plug for the time being.

Excellent idea. You have enough problems without adding "critters in heater" to your list.

[Susquatch]

Originally Posted by herk7769

Excellent idea. You have enough problems without adding "critters in heater" to your list.

Actually, maybe I should!!!! You are brilliant my friend!!!!! If I deliberately added some floatie "critters" in there while I drive around with the tank half full, that are smaller than the drain hole and slightly lighter than water, they might knock all the crap off the inside of the tank!

Hmmmmm, what to use...... Cork is too light and too energy absorbant, marbles sink, ice cubes are PERFECT but .... they won't last more than a few miles, little bird eggs are too fragile, gravel is too heavy, plastic chunks might melt later if I don't get em all out, ........

Hmmmmm, ..... how about walnut shells! Well known for use as a polishing medium for gems and metals, not too abrasive, floats until water logged, broken edges will catch on almost anything, won't break down into smaller parts if I sort em beforehand, easy to remove afterward,

Anyone know what the burner surface looks like on the inside of the tank? Is it just a flat surface or is it finned? If its finned. I prolly won't bother with anything other than a chemical approach (vinegar) as suggested by Windrider. If its smooth, then large pieces of walnut shells are promising!

Thanks!!!!

[Susquatch]

Originally Posted by windrider

Just venturing a guess here, never tried it, don't know, PROCEED AT YOUR OWN RISK. Create a mixture of 5 gallons of water and 5 gallons of WHITE vinegar........

Just couldn't leave home without testing the vinegar idea. I put a flake of the stuff in a glass of 50/50 water and vinegar. Nothing. Even pure white table vinegar does NOT touch the stuff. Of course, even pure vinegar is diluted. But even so - absolutely nothing going on there!!!!!

A stronger (yet still not too strong) acid like muriatic or the like might work. Might try some Pool pH up or down in a glass of water before trying muriatic. In any event, all that I expect a solution to do is loosen the flakes. There are a lot of deposits in there - a whole anode rod's worth, plus whatever it is in the antifreeze that it combined with. Probably way too much to "dissolve" (I know, "dissolve" is not the right word, but it is probably the best one to use for this forum) in an acid that won't also dissolve my tank!!!! Definitely plan to try some walnut shells in a half full tank before trying any stronger acids. Regardless, all these things will simply have to wait till I get home.....

Cheers!!!!

[Herk7769]

I am thinking this is a zinc compound from the corroded anode and not a calcium salt (also known as scale - vinegar works on this).

The fact that the RV anti-freeze was the corrosion agent is troubling since it is mostly Methanol (an alcohol) and water. I think blasting it out with a pressure washer through the anode port is going to be the your best bet.

I will look into this further and get back to you.
http://scitation.aip.org/getabs/serv...ifs=yes&ref=no

It appears if your water is sufficiently "acid" the methanol in RV anti-freeze can actually "speed up" the decay of the anode. The anode's job is to corrode naturally to keep acid water from eating away at the boiler. The methanol in RV anti-freeze apparently makes the process "more efficient".

[BigDTx]

Maybe you can try to fill the water heater with a soloution of CLR and water and let it soak for about 5-10 minutes then drain and flush?

When the service guy sanitized our water heater he had a rubber type hose that was about 1/4" and sprayed a bleach soloution itto the tank and the hose just whipped around and sprayed everything through the anode opening, maybe you can rig something up that will work.

[caper]

I would not use CLR it is an acid. I would use a copper pipe with a plug on the end. I would drill a small hole on the side of the pipe, install a female water hose fitting on the other end.Use the pressure to flush the WH tank.

[leencharlotte]

Sorry to hear about your problem. All 3 thoughts I had, vinegar, CLR and water flushing have already been mentioned so my response is for next winter

I thought I remembered ( and I could be backwards on this) reading somewhere that you should not leave the rod in when not in use. Yes, I understand the cold in Canada, but if the small remnants of water have room the expand ( no rod in place ) would that be ok for next winter?

If anyone can say different please let me know as I am somewhat new and this will be my first upcoming winter (NC not Canada though)

[flyrotor]

leencharlotte, that's true about room to expand, as everyone can see that you fill an ice tray and the water swells when freezing but never damages the tray, the problem occurs mostly in pipes when it has a closed circumference.

[leencharlotte]

Originally Posted by flyrotor

leencharlotte, that's true about room to expand, as everyone can see that you fill an ice tray and the water swells when freezing but never damages the tray, the problem occurs mostly in pipes when it has a closed circumference.

Again I am somewhat new to this but if the rod is not installed would that allow for expansion since it is not pressurized ?

[j2detroit]

i have had our tt for 6 seasons and winters i was told by the service mgr when we bought our camper to pull the anode rod while your doing your first drain down when winterizing and switch your bipass close leave the rod out till the next season ive done thin every year works great

[flyrotor]

Actually a small amount of water (residual after draining) will probably have enough room for expansion, by leaving the anode out this leaves an air vent, depending how early one winterizes their trailer, temps and avg humidity, there is a good chance the water will evaporate out the anode opening long before reaching freezing temps. Climate will either help or hinder the evaporation process.

[crocus]

I don't think I have ever heard of anyone draining their hwt and then putting the plug back in, and filling it with anti-freeze. There simply is no point. The little bit of water left in the bottom of the heater tank can freeze with no effect, or it will simply evaporate as another poster mentioned.
As for cleaning that white crud out of the tank, you could try taking the pressure relief valve out (at the top of the tank), and go to a car wash and stick the wand in that opening. The hot water and detergent might do some good.
One way or another, you should try to get the tank clean, as that white stuff may be poisonous.

[Susquatch]

Originally Posted by caper

I would use a copper pipe with a plug on the end. I would drill a small hole on the side of the pipe, install a female water hose fitting on the other end.Use the pressure to flush the WH tank.

I already did something similar. I bent some flexible copper tubing and then squeezed the tip so it formed a good nozzle. It helped, but not a lot.

Cheers!