By Russ and Tiña De Maris
Just because you winterized your RV doesn’t mean you can’t use it. Plenty of RVers get the sudden “hitch itch” in the middle of a cold winter, and to escape “cabin fever” head out on the road with the RV to see how things look when Jack Frost is running the show. But just how, some wonder, can you use the biffy? Hang on, pardner, there’s no need to cross your legs in discomfort until you hit a rest area!
Really, the biggest problem for RV plumbing in cold weather is when there’s water in the water lines. A bit of liquid in the holding tanks isn’t generally a problem. So while you might not want to put water in your fresh tank and use your water pump, you can still use the toilet. But then there’s that rather delicate issue – how on earth can you keep your RV bathroom from stinking to high heaven if you can’t flush the toilet?
HERE”S A HINT to help keep down costs. You don’t necessarily have to grab a gallon jug of antifreeze and just “glug, glug, glug” dump a bunch down the hatch. If your unwanted wastes drop out of sight when you step on the toilet evacuation pedal, then all that remains is probably a light coating of liquid in the bowl. If you fill up a plastic spray bottle with antifreeze, just hold the bowl flapper open and spray a generous jet or two of antifreeze around the bowl to eliminate any unwanted leftovers. This will keep your expenses down, and unwanted odors, too.

Ah, here’s where winter alternative thinking comes in. While it’s a bit more costly than using water, savvy winter RVers know they can flush their RV toilets – and keep things from icing up in the “down under” area of the black water holding tank – by using RV antifreeze to flush with. Yes, sir. Use the “pink stuff” to clear those unwanted leftovers from the toilet bowl.
Some RVers have suggested it might be less expensive to use cheap windshield washer fluid. There’s a bit of controversy over that offer – some say it works great, while others have complained that when they used the stuff, it damaged their dump valves. The counter-argument is, “If it doesn’t damage the rubber in your windshield washer system, why would it damage the rubber seals in your dump valves?” Your wise RV sages can only say, “Duh, we don’t know.” But we do know that the cost of a gallon of RV antifreeze isn’t that much more expensive than windshield washer fluid, so why chance it?
So grab your antifreeze and your road maps. Winter roads are calling!
My wife and I have a 40 foot Monaco diesel pusher and live in central Indiana. We absolutely love to winter camp, actually any type of camping is A-ok in our book! I kept track last winter how many times we winterized and dewinterized our rig, it was 21 times. I just blow out the lines and add a little rv antifreeze in the traps and in the washing machine. When we want to go camping, all we have to do is put some water in and go. We keep the heat on and have a heated wet bay area for when water is on board. Works great for us and its a pretty cool experience to pull into a campground and being the only people there! We love it!
Use a bucket with plastic bags in the winter
RV antifreeze WILL freeze. It starts as a slush. The real property is that when it DOES FREEZE, it will not EXPAND as water does. It’s the expansion of frozen water that cracks pipes. BTW, that slush behaves more like solid ice so don’t try spinning the pump thinking you can use it to flush because the fresh tank has antifreeze in it.
If you’re using the RV, and heating it at night, the chance of water freezing in the toilet bowl is close to 0%. Or leave the propane heater on low while you travel.
When storing my RV with temps dropping below the mid-20’s at night, I do put antifreeze in the toilet bowl.
Freezing causes damage when there’s nowhere for the ice to expand.
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I think the chance of freeze damage to an RV is overstated. I drain my lines and do a quick air-blow-out. But PEX tubing is pretty freeze resistant. I’ve seen comments on plumbing forums that P-trap freezing isn’t a problem as long as water isn’t high enough to reach pipe threads.
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RV Travel should find an expert to do some articles on the risks of RV freeze damage and what I suspect is all the money and time wasted on antifreeze and winter prep.
We do what Ed said put small amount antifreeze in tank and then use regular water in a spray bottle. Not to mention at least while you are moving things will slosh around. Add in the pee and not likely to freeze. 😊
Or, get a composting toilet — no plumbing no freezing 🙂
Thank you for the tips, but thank you even more for relentlessly writing so many excellent and informative articles for RV Travel and its readers, such as me. It must be a labor of love because writing well, as you do, takes a lot of work — thinking, writing, and then rewriting several times to make sure it is right and concise. THANK YOU! 🙂
I put some antifreeze in the tank and then just flush with a jug of water
I like this idea!