Non-toxic RV Plumbing Antifreeze

[Bob Stone]

The RV plumbing antifreeze sold by both Lowes and Home Depot in Canada is the same brand. Both hardware websites indicate this product is for plastic water line use only and not to be used in metal pipes. My concern is the copper pipes in the Aquahot/Hydrahot heat exchanger.

I'm afraid their warning may be due to something in this antifreeze that will corrode the metal. If the issue is minor leaching of the metal which renders the potable water lines potentially toxic this is of minor concern to me as I always only drink bottled water. I have a query to the company but do not expect a prompt response.

The antifreeze will only be in the lines for a month if that is of any consequence.

All comments and opinions are much appreciated.

Thanks
Bob Stone

[Edward Buker]

All of the non toxic antifreeze that I am aware of has been propylene glycol based. Glycol degradation can form an acid over time that can etch metal at a very slow rate. These reactions are temperature sensitive and the fact that you are using this for limited time and not heating the fluid would mean that you have nothing to worry about. There are versions of the propylene glycol based antifreeze that have inhibitor packages in them for use with metals.

In your case you can also keep the concentration of the solution at the minimum concentration that is needed for the temps you will encounter. It is much easier for the manufacturer to just indicate on the label not for use with metals so that there is no liability. They do not have to specify a range of caveats for use with various metals either. I'm sure that this antifreeze version has been used for years for most all marine and RV system winterizations with many mixes of metal and plastic materials and I have never heard of a real life problem.

Later Ed

[Bob Stone]

Thanks Ed, that's what I suspected but needed another opinion. Ironically the manufacturer doesn't give the 'plastic only' warning in their product literature.
When/if I get a response from the manufacturer I'll be sure to post their comments.

Bob