Everything you need to know about RV antifreeze.
by Sue Mosebar
EVERY RVER HAS ABOUT THREE OPTIONS EACH WINTER. The first is to run for it! The second is tough it out. The third is to put those travel plans on hold and let your RV take a long winter nap. And if you’re going with Option 3, you’ll need to get to know a magical elixir known as “the pink stuff”—aka RV antifreeze.
Two Very Different Kinds of Antifreeze
RV antifreeze has an important job to do: lower the freezing point of any water left in your RV to protect your pipes and fittings from bursting, breaking, and becoming an inconvenience. When added to the water system, RV antifreeze can lower the freezing point. This then prevents any remaining water from expanding when temperatures drop below freezing, which can damage the pipes, leading to leaks or even bursting pipes. Some types of RV antifreeze also help protect the seals, such as in faucets or toilets, by acting as a lubricant. The pink stuff, which is non-toxic, is certainly not to be confused with car antifreeze.
Auto antifreeze has a completely different purpose (helping cool the engine), is totally toxic, and should never be used anywhere near your potable water sources. Like ever. The pink stuff, however, is considered safe, non-toxic, and non-hazardous. And if you think about it, it has to be. Because it’s going into your water pipes. Of course, that doesn’t mean you or your pets should try it. And that’s good to remember because, dogs and cats may be attracted to the sweet smell and taste of propylene glycol—and even small amounts can lead to a type of severe anemia or liver failure in cats. (Good to remember as you start winterization.)
Choosing an RV Antifreeze Option
There are three common types of RV antifreeze: ethanol-based, propylene glycol-based, or (less commonly) an ethanol/propylene blend. Ethanol is an alcohol, and propylene glycol is considered a double-strength alcohol. Both types act to lower the freezing point of any water left in the tank. The type, as well as the brand, of antifreeze, can determine how effective the RV antifreeze is for your uses. In more moderate climates, a less expensive ethanol RV antifreeze may be enough. However, the most common type of RV antifreeze is propylene glycol. It’s often preferred for several advantages. For example, propylene glycose-based products: are nonflammable, so they’re safer than ethanol-based antifreeze; are lubricating, so they are better at protecting the seals in your plumbing system; leave less residual taste or smell than ethanal-based varieties, which can also take longer to wash out of the system; and are nontoxic to humans when used as directed, even in the freshwater system.
How to Use RV Antifreeze
RV antifreeze can be added either alone (after pipes have been cleared of water) or combined with the remaining water after you’ve drained your pipes as much as possible. It can also be poured into p-traps in the sinks and shower so they don’t freeze solid and get damaged. Finally, the pink stuff can be added to the gray and black tanks, so waste doesn’t freeze if you’re camping when winter weather arrives. That way, you can still easily dump your waste at the end of the journey even when the temperatures drop. (Alternatively, you can skip the pink stuff altogether by ensuring all water is completely blown out of the plumbing system with high air pressure, perhaps adding a small amount of antifreeze to plumbing p-traps to lubricate and prevent any leftover liquid from freezing.)
Once it’s time to use your RV again, you’ll need to de-winterize it, which will mean flushing the freshwater tank and the entire system with fresh water before the water is okay to consume. Remember to drain it at a dump station, sewer hole, or septic tank rather than into the ground as, again, even if it’s labeled as non-toxic, it’s not safe for many animals and can be harmful to the environment, especially if it leaches into a water source.
Prevention Puts You in the Pink
Whichever version or method you choose, it’s important to winterize your RV to protect the plumbing system. Remember, most RVs aren’t designed to be well-insulated when the temperatures drop well below zero. And many have somewhat exposed plumbing systems that are more susceptible to damage from freezing temperatures. Protecting the pipes, water pumps, p-traps, holding tanks, and water heaters is crucial. Otherwise, you’re likely to uncover burst pipes, leaks, and expensive repairs to make before you can hit the road in the spring. And no one’s got time—or money—for preventable repairs.