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RV ANTIFREEZE
Propylene glycol
Propylene glycol, on the other hand, is considerably less toxic and may be labeled as "non-toxic antifreeze". It is
used as antifreeze where ethylene glycol would be inappropriate, such as in food-processing systems or in water
pipes in homes, as well as numerous other settings. It is also used in food, medicines, and cosmetics, often as a
binding agent. Propylene glycol is "generally recognized as safe" by the Food and Drug Administration (FDA)
for use in food. However, propylene glycol-based antifreeze should not be considered safe for consumption. In
the event of accidental ingestion, emergency medical services should be contacted immediately.
Propylene Glycol oxidizes when exposed to air and heat. When this occurs, organic acids are formed – Glycolic
acid, Glyoxalic acid, Formic acid, Carbonic acid & Oxalic acid. If not properly inhibited, this fluid can be very
corrosive. Protodin is added to Propylene Glycol to act as a buffer, preventing low pH attack on the system
metals. It forms a protective skin inside the tank and pipelines which helps to prevent acid attack that cause
corrosion.
Beside cooling system breakdown, biological fouling also occurs. Once bacterial slime starts the corrosion rate
of the system increases. In system where a glycol solution is maintained on a continuous basis, regular
monitoring of freeze protection, pH, specific gravity, inhibitor level, color and biological contamination should
be checked on routine basis.
Propylene glycol should be replaced when it turns reddish in color.
From Prestone Products Corporation:
“RV Waterline Antifreeze” is ideal for winterizing all types of potable water supply systems. Recommended for
use in boats, trailers, recreational vehicles, vacation homes, swimming pool filtration and heating systems.
Unsurpassed rust and metal protection for all metal pipes commonly found in water supply systems.
To Winterize Systems Generally:
1. Turn off fresh water supply.
2. Completely drain water lines at all outlets thoroughly following manufacturer’s directions.
3. Refill systems to capacity with undiluted Prestone RV Antifreeze.
4. Re-pressurize water supply system.
5. Open all hot and cold faucets one at a time to see if system is full. Pink color confirms system is full.
To De-Winterize Systems:
1. Open all hot and cold faucets and run fresh water through system until all color disappears.
2. Flush several times until all color disappears.
3. Fill fresh water supply tank.
