Put Car Antifreeze in Fresh Water Holding Tank

by Carleton
(Columbus, OHIO)

How do I, or is it possible even possible, clean automobile antifreeze from an RV freshwater holding tank - so that it is safe to provide potable water!?

ANSWER: Hi Carleton obviously you cannot use the water out of this holding tank because the Antifreeze that is used in cars is highly toxic and should never be used to winterize an RV.

The freshwater system on your RV needs to be cleaned out. My suggestion to you is if you know who manufactured the antifreeze is to contact the manufacturer and see what suggestions they have for you to get rid of the antifreeze in your freshwater system.

You may also want to contact the National Poison Control Center to see if they have any suggestions for you.

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This is one of the times where I really do not have any suggestions on how to properly clean this up, because of the potential serious health effects this could have if it is not properly done.

Do you have any suggestions or comments on this topic? You can add them to this page by clicking on the "Click Here To Post Comments" link located near the bottom of this page.

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Happy RVing

RVing Al

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Cleaning Water Tank with ethylene glycol
by: Anonymous

Regarding the question about ethylene glycol in the drinking water tank: Ethylene glycol is extremely toxic in concentrated forms but it can be both diluted and evaporated away. It also degrades over time with the amount dropping by half every 48 days in the presence of oxygen. So time, evaporation and water are your friend.

One problem is the stuff is environmentally highly toxic so you want to collect as much as you absolutely can and dispose of it properly as the toxic waste it is. Drain the tank completely. Flush with a small amount of water water and collect the water. Allow the tank to dry completely. If you leave the tank to dry with the antifreeze undiluted you are risking a fire because the fumes are flammable.

I would then recommend flushing the tank out with copious amounts of water and then allowing it to dry completely three times with the tank open to the air. This should remove all but trace residue by a combination of dilution and evaporation, including that which may bound to the plastic. Even so, you may have minute amounts left in the water. I would make sure any water used for cleaning dishes is filtered through activated charcoal and use a separate source of drinking water for a full season.

There is no evidence of any toxicity if it is accidentally ingested in minute barely trace amounts but I suspect it can't be good for you. Hence adding in a time factor as an extra safety margin. By using a combination of dilution, and evaporation and time you should be fine.

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