Learning how to winterize rv washing machine units is one of those tasks that feels like a massive headache until you actually do it. Let's be real—nobody wants to spend their Saturday afternoon messying around with plumbing and pink liquid, but it's a whole lot better than waking up in the spring to a cracked pump and a flooded floor. If you've ever had to replace an RV appliance, you know they aren't exactly cheap, and the labor costs for those tight spaces are enough to make anyone's eyes water.
The thing about RV washing machines is that they're surprisingly delicate when it comes to freezing temperatures. Unlike the pipes in your home, which are usually buried deep or somewhat insulated, RV plumbing is often exposed to the elements. Even a tiny bit of leftover water in the internal valves or the drain pump can expand as it freezes, and before you know it, you've got a plastic housing that's split right down the middle.
Why you can't just leave it alone
You might think that if you've drained your main water tanks, you're good to go. Unfortunately, washing machines are a bit of a "trap" for water. They have internal reservoirs, pumps, and solenoids that hold onto moisture long after you've turned off the main water supply.
When that water turns to ice, it doesn't just sit there. It expands with incredible force. I've seen seasoned RVers lose entire units because they forgot about that last cup of water sitting in the bottom of the drum or the supply lines. So, taking thirty minutes to do this right is basically an insurance policy for your rig.
What you're going to need
Before you start, grab a few things so you aren't running back and forth to the hardware store. You'll definitely need:
- RV Antifreeze: Get the pink stuff (Propylene Glycol). Do not use automotive antifreeze; that stuff is toxic and will ruin your plumbing and potentially your health.
- A bucket: To catch any rogue drips.
- An air compressor (optional): Only if you prefer the "blow-out" method, but even then, I usually recommend a little antifreeze for the pump.
- A friend: It's way easier if one person is at the controls and the other is watching the lines.
The Antifreeze Method: Step by Step
This is the most common way to handle things. It's reliable because the antifreeze literally replaces the water, so there's no room for air pockets or hidden moisture.
1. Drain the lines
Start by turning off your water pump or disconnecting from city water. Open up your low-point drains to get the bulk of the water out of the RV's system first. Once the lines are mostly empty, close the drains back up. You want the system closed so you can pressurized the antifreeze later.
2. Get the antifreeze into the system
Most modern RVs have a winterizing bypass valve near the water pump. Flip that valve and put the siphon hose into your jug of pink antifreeze. Turn on the water pump. Now, your RV's plumbing is pressurized with the "pink stuff" instead of fresh water.
3. Run the "Hot" cycle
Head over to your washing machine. Turn it on and set it to a "Warm" or "Hot" wash cycle. Start the machine and wait. You'll hear the valves click open. Keep it running until you see that bright pink liquid start pouring into the drum. This ensures the hot water solenoid and the line leading to it are completely protected.
4. Run the "Cold" cycle
Switch the setting to a "Cold" wash. Again, wait for the pink antifreeze to start flowing into the machine. Once you see a solid stream of pink, you know the cold side is safe.
5. Don't forget the pump and drain
This is the part people usually miss. Just because there's antifreeze in the drum doesn't mean the pump is safe. Set your machine to "Spin" or "Drain." This will force the antifreeze through the internal pump and out through the drain hose. You want to see pink liquid coming out of the discharge hose into your grey tank (or a bucket).
The Blow-out Method
Some people prefer not to put antifreeze through their machine because they worry about the smell or the residue. If that's you, you can use compressed air.
You'll need a "blow-out plug" for your city water inlet. Set your compressor to about 20-30 PSI—don't go higher or you'll blow the seals right out of your machine. With the air running through the system, cycle the washing machine through hot and cold settings until only mist or air comes out.
A quick tip: Even if you use air, I still highly recommend pouring about a half-gallon of RV antifreeze directly into the drum and running a quick "Drain" cycle. This protects the drain pump and the "P-trap" in the plumbing, which air alone often can't clear out entirely.
Special considerations for stackable units
If you have a separate washer and dryer, the process is pretty straightforward. However, if you have a combo unit (like those popular Splendide models), they sometimes have a "winterization" setting or specific button combinations to clear the lines. Always check your manual if you have one, but generally, the "run it until it turns pink" method works for almost every brand out there.
If your unit is in a particularly tight closet, you might find it hard to see the lines. This is where a flashlight and a small mirror come in handy. You want to make sure there are no leaks around the intake hoses while you're doing this, as the extra pressure from the pump can sometimes expose a loose connection.
Common mistakes to avoid
One big mistake is forgetting to empty the lint filter or the "coin trap." Many RV washers have a small door at the bottom front. Water loves to hide in there. Open it up, let it drain into a towel, and then close it back up before you start the antifreeze process.
Another thing is the water heater. If your washing machine draws from the water heater (which it obviously does for hot cycles), make sure your water heater is bypassed and drained before you start the washer. You don't want to fill a 10-gallon water heater with expensive antifreeze just to get a little bit to the washing machine.
What to do when spring rolls around
Once the birds start chirping and the ice melts, you'll need to reverse the process. This is basically just running the machine on a "Heavy Duty" cycle with plenty of fresh water and maybe a little extra detergent or a specialized washer cleaner.
Run it at least twice. The first time gets the pink stuff out, and the second time ensures there's no lingering scent. You definitely don't want your first load of white t-shirts coming out with a slight rose-colored tint.
Final thoughts
It feels like a lot of steps, but once you've done it a couple of times, you can winterize the whole machine in about ten minutes. It's just part of the rhythm of RV life. Taking the time to learn how to winterize rv washing machine setups properly means you can spend your winter worrying about where you're going to travel next, rather than worrying about a plumbing disaster waiting for you in the driveway.
Stay warm, keep those lines clear, and your RV will be ready to hit the road as soon as the weather breaks. It's a small price to pay for the convenience of doing laundry on the road!