Antifreeze-Why is RV Antifreeze not ok for Hydronic Heating?
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Antifreeze-Why is RV Antifreeze not ok for Hydronic Heating? My hardware store says I can use the cheaper RV antifreeze to keep my baseboard pipes from freezing if my boiler fails. However, the manufacturer on the gallon bottle says NO. Whats the difference?
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I believe RV Anti freeze is not intended for heat transfer-But I don't know why?
Automotive anti freeze is certainly designed for heat transfer and is readily available and chaper- Why don't we use auto Anti freeze in our home hydronic systems? Posters Please Comment.
The cheaper RV antifreeze is usually ethanol based and very flammable. The more expensive stuff is propylene glycol based.
In a hydronic system ethanol will likely become depleted, escaping in gas form via the system's air vents. But it will also degrade any rubber gaskets & seals.
Propylene glycol is pretty commonly used in hydronic systems, but has material compatibility issues with some systems, and can be corrosive to some materials. Propylene glycol antifreeze products specifically designed for hydronic systems has additives designed to mitigate those issues.