Winter is Coming: How (and When) to Winterize Your RV

RVing in the fall is stunning. Some of the best nights we’ve spent in an RV were in October and November, with the windows cracked and golden leaves falling through the air. 

And that’s where the warm and cozy feeling ends… 

Shortly after, it’s time to put the RV away for winter. “Winterizing” is essential to avoid damage and ensure your RV will be ready to go again when spring arrives.

This article covers the importance of winterizing, when you should do it, and a couple of different methods to make it happen. Some brave RVers might want to camp in the snow, which we enjoyed doing ourselves (once), so we’ve also got a short section on winter camping for those brave souls.

Why is winterizing important?

As the name implies, winterizing means getting your RV ready for the freezing temperatures that come along with winter in most places. Most often, you’ll winterize your RV prior to storing it for a few months while it’s too cold to travel. (This isn’t always the case, though—more on that in the next section.)

There are a few different ways to prepare your RV for long-term storage. You’ll want to close windows and vents, clean your fridge and freezer thoroughly, shut everything off, and properly store your battery. 

In general, though, “winterizing” is the process of draining the plumbing system protecting it against damage during the cold winter months. If you’ve ever had frozen pipes or water lines in a house, you know that when water freezes and expands, it’s bad news for any type of plumbing. RVs are no exception, especially since they aren’t as well insulated as most sticks and bricks homes. Any water in your tanks or water lines can crack pipes and connection points if it freezes, which could make for costly repairs come springtime.

When should you winterize your RV?

You’ll want to winterize your rig in two different scenarios: storing your RV for the winter, and very cold weather camping.

If you’re a part-time or weekend camper, you’ll likely be putting your RV in storage for the winter months. If that’s the case, you should winterize your RV’s plumbing before you store it to prevent damage.

Even if you’re a full-timer or snowbird, you still might need to winterize your RV, depending on how you’re traveling, where you are, and how low the temperatures get.

As a general rule of thumb, even if your RV is in use, you should probably winterize if:

• Temperatures are consistently at 20 degrees Fahrenheit or lower
• You can’t insulate and heat your RV’s underbelly, or you don’t have heated tanks
• You’re boondocking and can only run your furnace at certain times

Not a DIYer?

No problem! Winterizing is a simple task to do yourself. Depending on the method you use and the size of your rig, the whole process will take you less than an hour. Dealers might charge $200 or more for a winterizing service, but doing it yourself can cost less than $25 (the price of 2 gallons of antifreeze).

Winterizing Method #1: Antifreeze

The simplest, easiest method for winterizing your plumbing is RV antifreeze. You’ve probably seen those pink gallon-jugs at your local Walmart or camp store. The pink stuff is RV/marine antifreeze, which is nontoxic. Since you’re running it through your drinking water lines, it’s very important to buy the nontoxic pink variety! Do not use automotive antifreeze, or any other type.

Here’s what you’ll need: All items listed below are on our Amazon Storefront under Winter Camping & Winterizing.

• 2-3 gallons of non-toxic RV antifreeze, depending on the size of your rig (the bigger your rig, the more you’ll need)
• Water heater bypass kit, if your RV doesn’t have one pre-installed
• Black tank flush wand or nozzle, if your RV doesn’t have one pre-installed
• Basic hand tools to remove and reinstall the water heater drain plug
• Water pump converter kit, or tubing to connect to the inlet side of the water pump

Before You Start: Read Your Owner’s Manual

This article will share the general steps required to winterize an RV, but your owner’s manual describes any considerations you should take into account for your specific rig. Your manual will talk through important specifications, like where and how to bypass your hot water heater, the amount of pressure your water lines can handle, and any extra steps you’ll need to take to get your RV ready for winter.

In short, this article should be read as an addition to the processes described in your owner’s manual—not a replacement!

Step 1: Drain Your System

The first step to winterizing is a very basic one, and something you should do any time you store your RV for a while, regardless of weather.

Drain every tank in the RV. Disconnect and drain your fresh water hose, and turn off your water pump.

While connected to a sewer dump, empty and flush the gray and black holding tanks, to be sure they’re clean and ready for storage. If your RV doesn’t have a built-in black tank flush, use a tank cleaning wand or a flush nozzle to rinse out the inside of the tank. 

Open the low point drain on your fresh water tank, and let all water drain from that tank, too. Close this valve again when you’re done. You won’t put any antifreeze in the fresh water tank, so once it’s done dripping, you’re good to go.

Turn off your hot water heater, and wait several hours before moving on to Step 2.

Step 2: Drain Your Hot Water Heater

A word of warning: turn your hot water heater off several hours before doing this. When you remove the drain plug, 5 or more gallons of water will come rushing out at you. You do not want to get scalded when that happens, so be sure your water heater is turned off prior to draining, and give the water time to cool. 

You’ll also want to be sure the system isn’t pressurized. Disconnect from any water source, turn the water pump off, and open a hot water faucet prior to draining. This, and the pressure relief valve, will ensure that the system isn’t under pressure when you drain it.

When you’re ready, open the pressure relief valve, and remove the drain plug or anode rod. Your water heater will drain onto the ground very quickly, so stand back! If you have a Suburban brand water heater with an anode rod, now is a good time to replace it if you need to. If you’re planning to clean your water heater with a tank-rinsing wand or vinegar solution, now is a good time for that, too.

Once the water heater has drained, wrap fresh plumber’s tape around the threads of the anode rod or drain plug, and reinstall it.

If you have any inline water filters for drinking water in your RV, remove them. Turn any valves so that you bypass those lines before continuing.

Step 3: Drain Interior Lines

With your gray tank dump valve(s) open, turn on all hot and cold faucets. Don’t forget the kitchen wand, toilet, and outdoor shower. Locate and open any low point water drains. Then, use the water pump to force any remaining water out of the lines. Don’t run the water pump for more than a few seconds; as soon as the system is dry, turn off the pump so you don’t damage it.

Recap all drains, and close all faucets. Close your gray tank valves and disconnect from the sewer. Rinse and stow your sewer hose.

Step 4: Bypass Your Water Heater

Many RVs have a bypass kit already installed; you’ll know from reading your manual whether yours has a system like this or not. If it does, your manufacturer will usually provide you with a diagram. The system is usually accessible inside the RV behind a removable panel, behind the water heater, or through the basement.

Don’t skip this step! It’s important to bypass your water heater so you don’t fill that 5-6 gallon tank with antifreeze. Not only is it unnecessary and a waste of “the pink stuff,” it’s also a hassle to rinse it out when you’re ready to camp again in spring.

Step 5: Bypass Your Fresh Water Tank

Now, you’ll use your water pump to run antifreeze through your water lines.

Some RVs have a winterization valve pre-installed in the fresh water system. If yours does, turn the valves to their correct position to bypass the fresh water tank. There’s usually a diagram near this system, or in your RV user manual. There should be a tube that you can place directly into a jug of antifreeze. 

If you don’t have a system like this pre-installed, use a water pump converter kit. Or, disconnect the line coming from the fresh water tank to the water pump, and replace it with tubing that runs from the water pump inlet into a gallon jug of RV antifreeze.

The goal here is to draw antifreeze directly into your RV’s water lines, but NOT into your fresh water tank.

Step 6: Run Antifreeze Through Your Water Lines

With the water pump inlet tube in a gallon jug of antifreeze, turn on the water pump to pressurize the system. You’ll see the level of antifreeze go down as it’s drawn into your lines, but you aren’t done yet!

Now, open up every faucet in your rig, one at a time, to run antifreeze through the system. Do this with both hot and cold valves to fill both lines. Keep the faucets open until you see pink antifreeze, then shut them off.

Run antifreeze through every line, including: drinking water taps (with the filter removed and bypassed), kitchen sprayer, toilet flush and wand (if you have one), and interior and exterior showers.

When you’re finished, turn off the water pump.

Step 7: Pour Antifreeze Down the Drains

Now, pour a cup of antifreeze down each drain. This will protect your P-traps from freezing. (If you’ve ever been to an RV show and seen pink stains in the sinks and the toilet, this is why!)

Pour about 2 cups of antifreeze into the toilet bowl, and flush it into the holding tank to prevent any residual water from freezing. Then pour another cup or two into the bowl and leave it there to protect the valve.

Step 8: You’re Ready for Winter!

That’s all there is to this method, which is one reason why we love it. It’s quick and easy, and can be done in a very short time if you need to winterize in a pinch.

Winterizing Method #2: Compressed Air 

This method is more thorough, but also more time-consuming. You’ll still need RV antifreeze, plus a few other gadgets.

Here’s what you’ll need:

• A tankless air compressor. We love the Viair compressor with a built-in air filter, which helps make sure no contaminants are blown into the fresh water system. (It’s also great for filling your RV or truck tires, since it can pressurize up to 150 PSI.)
• A blow-out plug to connect the air compressor to your fresh water system.
• An adjustable water pressure regulator to attach inline with the blow-out plug, to protect your system from getting overpressurized. You’ll want to set the regulator to 50 PSI or less (consult your RV owner’s manual for requirements specific to your system). 

Getting Started

Follow Steps 1 and 2 from the Antifreeze method, to drain your system and your water heater. But, don’t replace the drain plug or anode rod in your water heater at the end of Step 2

Step 3: Blow Out Your Hot Water LInes

Close the pressure relief valve on your hot water heater, and with the drain plug open, connect your air compressor assembly (specifically the blowout plug) to your fresh water inlet. Make sure you have a pressure regulator or an adjustable air compressor so you don’t over-pressurize your water lines.

Then, turn on the air compressor, and pump compressed air through the lines. You’ll see more water come out of the drain plug as water drains from the hot water lines. Once you’re done, replace the anode rod or drain plug and make sure the water heater is shut off for storage.

Step 4: Bypass the Water Heater and any Filters

Many RVs have a bypass kit already installed; you’ll know from reading your manual whether yours has a system like this or not. If it does, your manufacturer will usually provide you with a diagram. The system is usually accessible inside the RV behind a removable panel, behind the water heater, or through the basement.

Remove and bypass any inline water filters, too.

Step 5: Blow Out All Water Lines

Your water pump should be turned off throughout this step.

Open your low point drains, and then open every faucet in the RV to a “warm” setting. Once there’s no more water coming from the low point drains, close the drains and shut off your faucets.

Then, open one faucet at a time on both cold and hot settings, and blow compressed air through the system until there’s only air escaping the faucet. This is easiest with a partner, but if you’re working solo, about 30 seconds of compressed air through each faucet should be plenty. Be sure to open just one faucet at a time, and don’t forget the kitchen sprayer, shower head, toilet, and outdoor shower.

To drain the water pump, turn on your outdoor shower nozzle, and then turn on the water pump. Don’t let it run for too long, since your fresh water system is dry; you just want to drain it. You can use compressed air to blow water out of the line.

Step 6: Pour Antifreeze Down the Drain

Pour a cup of antifreeze down each drain. This will protect your P-traps from freezing. (If you’ve ever been to an RV show and seen pink stains in the sinks and the toilet, this is why!

Pour about 2 cups of antifreeze into the toilet bowl, and flush it into the holding tank to prevent any residual water from freezing. Then pour another cup or two into the bowl and leave it there to keep the valve from freezing.

Close the fresh water tank low point drain, close all gray valves, and make sure your sewer hose is drained and stored.

Here are a few Do’s and Don’ts to keep in mind, regardless of which method you use:

Do:

• Turn off your water heater, even if you’ve removed propane tanks from your RV for the winter. You want both propane and electric switches in the Off position. Do this well before you drain the water heater so the water has time to cool.
• Close all faucets, dump valves, and low point drains.
• Turn off the water pump prior to storage.
• Winterize your outdoor shower. Since it’s an outdoor line, it’s easy to forget—but it’s also the most exposed to the elements!

Don’t:

• Neglect other appliances that use water, like washing machines, dishwashers, or icemakers. Consult the owner’s manuals for these appliances to be sure you winterize them properly, too.
• Pour antifreeze into your fresh water tank. Even though it’s nontoxic, you don’t want to drink it!
• Forget to open the pressure relief valve when you drain your water heater. Otherwise, it won’t drain completely.

To Winterize or Not to Winterize: Winter Camping Tips

Don’t assume that you have to winterize your RV just because you’ll be camped in freezing temperatures. There are a lot of factors that determine when and how lines will freeze. 

If you’re at an RV park with hookups that allow you to run your heat overnight, and if your RV underbelly is insulated and/or heated, you’ll be fine even if the temperature dips below freezing. Just disconnect your fresh water hose from the spigot if the temperature will be around 27 degrees or less for an extended period; otherwise, you’ll likely have to wait for the hose to thaw before you can use water in the morning. 

One method we’ve used is just to fill the fresh water tank and disconnect from the spigot if temperatures will be well below freezing for hours at a time. In most cases, just running our furnace keeps things warm enough that we haven’t had an issue with things freezing up.

If you DO intend to camp in very cold temperatures, here are some steps you can take to prevent freezing:

• Skirt your RV. This basically means covering the gap between the bottom of your RV and the ground, so cold air can’t flow underneath it. You can buy custom-made skirts or make your own out of plywood and other materials easily sourced at hardware stores.
• Run a Heater. Once you have a skirt in place, put a small electric heater in the space below your RV. This prevents the underbelly from freezing.
• Warm Up Your Hose. If you’re at an RV park with a fresh water connection, buy or make a heated water hose. If you’re moving around a lot, the Camco heated water hose is a great option. If you’ll be in one spot for a while, and won’t need to connect/disconnect very often, you can buy heat tape and apply it to your regular fresh water hose. Either way, wrap the connection between the hose and spigot with heat tape to make sure the connection point doesn’t freeze. 
• Leave Water Running. On very cold nights, you can leave a faucet open so that some water is constantly moving  through the system to prevent freezing. (Be mindful of where you are—this method isn’t recommended in areas with a water shortage.)

And yes, you can still use your RV while it’s winterized! If you’re boondocking or camping in very cold places, you can winterize your RV and still go camping. You won’t be able to fill your fresh water tank or water heater, so you’ll need to rely on careful use of water jugs and antifreeze. Just add roughly equal parts antifreeze to your gray and black tanks as you add liquid to them, to be sure things don’t freeze up. This is especially important for the black tank. Take our word for it.

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