Your Guide to RV Winterizing

Nov 11, 2020 | Maintenance & Mods

Your Guide to RV Winterizing

We walk you through the RV winterizing process so you can protect your rig from potentially damaging elements and be ready to hit the road come spring.

By Rob Cochran

As the days get colder and darker, it’s time to start preparing your RV for freezing temperatures and curious critters. Come springtime, you don’t want any surprises. 

In this article:

There are a few ways to approach winterizing your RV: You can do it yourself, use a mobile RV maintenance company, or take your rig to a service center. This can cost anywhere from $75 to $200 depending on location and what services are included. How you winterize your RV will depend on a variety of factors like where you will be storing it—indoors, outdoors, or at a storage facility—and the climate you will be storing it in.

If you decide to do it yourself, follow these steps to winterize your motorhome, travel trailer, pop-up camper, or fifth wheel. 

Togo Tip: When you first purchase your RV, it’s a good idea to record your walkthrough on your smartphone so you have your own personalized resource for winterizing and dewinterizing. 

Airstream and tow vehicle parked at campsite with snow capped mountains in the background

How to Keep RV Pipes from Freezing

The best place to start is by protecting your RV’s plumbing system from freezing temperatures. Frozen water in lines or tanks can crack or break pipes, tubing, and fittings. This leads to expensive repairs and ample amounts of stress.

Can you leave your RV plugged in all winter?

Your RV can be left plugged in and kept warm during freezing temperatures to prevent issues. RV tanks are often mounted outside which can still cause a problem. Some RVs are equipped with tank heaters that can be used in this instance.

At what temperature do RV water lines freeze?

Several factors play into how fast a problem can occur in freezing temperatures. It’s best to take precautions anytime the temps will get below 32 degrees Fahrenheit.

Is RV antifreeze bad for the water heater?

RV antifreeze is non-toxic and is safe for both aluminum and steel type tanks.

How cold can it get before I have to winterize my camper?

If the temps are dipping down to freezing and you haven’t been able to winterize—don’t panic, just run the heater on low that night. Yes, it will cost you money in propane, but you will save your pipes and tanks.

Man pouring liquid into motorhome

Blowing Out RV Water Lines vs. Antifreeze

You can protect your RV pipes in one of two ways:

  • Fill the lines with antifreeze so they don’t freeze, or
  • Blow the water lines out with compressed air.

The antifreeze will protect your pipes more than blowing out the water lines as the air won’t completely blow out all of the water. However, you may not need to go the antifreeze route if you live in a warmer climate or are storing your RV indoors.

Antifreeze Method

One of the keys to your endeavor will be protecting your plumbing system. Here’s what a typical RV plumbing system looks like:

Graphic showing an RV plumbing system
What a typical RV plumbing system looks like.
  1. Drain your gray and black water tanks completely. 
  2. Disconnect your vehicle from your outside water source.
  3. Remove and bypass any inline water filters. Many new RVs will come with bypasses already installed, otherwise, this will require a water filter bypass hose you can install when the filter is out.
  4. Bypass your water heater using the factory-installed bypass kit. If your RV did not come with one, an aftermarket bypass kit can be installed.
  5. Check your owner’s manuals for specific instructions on winterizing your dishwasher, ice maker, and washing machine. These are all important to protect but will require a different procedure for each.
  6. Open all the faucets and flush the toilet to allow all excess water to drain. Don’t forget your tub and shower. Open your low-point drains and let the water empty. (Can’t find the low-point drains? Consult your owner’s manual or a qualified RV service center.)
  7. Drain your fresh water holding tank using the tank drain low point.
  8. Drain the water heater. Caution: Never drain the water heater when it’s hot or under pressure. Open the pressure relief valve to remove any pressure and leave it open. Using the proper wrench, remove the drain plug or anode rod and allow it to drain. Flush out any sediment with a rinsing wand. Close the pressure relief valve and loosely reinstall the drain plug or anode rod for safekeeping until you dewinterize.
  9. Connect the water pump converter kit, insert the tube into the antifreeze jug, and open the valve on the kit. If your RV did not come with one, an aftermarket bypass kit can be installed. Turn on the water pump to allow the antifreeze to pull into the water system. 
  10. Slowly open the hot and cold valves at the closest faucet to the pump, and close when the antifreeze appears. Repeat the process for all faucets, from closest to furthest, including the toilet.
  11. Turn the pump off and open a faucet to relieve pressure and close all faucets.
  12. Pour one cup of RV antifreeze into each sink and shower drain, allowing the antifreeze to protect the drain traps and flow into the gray tank. Pour two cups of antifreeze into the toilet bowl and open, allowing it to drain into the black tank.

Blow-Out Method 

If you do not want to fill your plumbing system with antifreeze, your other option is to blow it out with compressed air. You’ll need a portable air compressor and a special blow-out adapter that you can buy at most RV parts suppliers, as well as a gallon of antifreeze. Here’s what you do:

Follow steps 1 through 8 as outlined above. 

  1. Connect the blow-out adapter to the municipal water inlet. Make sure you connect the correct inlet. Some fresh water tank inlets and tank flushers look similar but may cause damage if air is applied to them. 
  2. Adjust the air compressor to a maximum pressure of 30 psi to avoid pipe damage.
  3. Connect the air compressor hose to the blow-out adapter. Turn on the compressor and let it run. Then go from fixture to fixture to let the air out, turning on each faucet, shower, and toilet for about 15 seconds. Finish with the low-point drains.
  4. Turn off the compressor and disconnect the blow-out adapter. Open any faucet to remove any leftover air pressure. 
  5. Pour one cup of RV antifreeze into each sink and shower drain, allowing the antifreeze to protect the drain traps and flow into the gray tank. Pour two cups of antifreeze into the toilet bowl and open the toilet seal, allowing it to drain into the black tank. 

Important Info on RV Antifreeze

When purchasing antifreeze for your RV winterizing process, make sure to buy a non-toxic antifreeze specifically for RV use.

Does RV antifreeze go bad?

RV antifreeze will safely store for several years but should be stored out of direct sunlight for best results.

How many gallons of antifreeze for RV?

Two gallons will cover an average-size RV. Large RVs may require more and very small RVs can usually get by with one gallon. If the water heater is not bypassed, you will require enough additional antifreeze to fill the hot water tank, which would typically require either 6 or 10 additional gallons.

How to Winterize Your RV Interior

Mice and other critters may attempt to make your RV a nice winter home. Follow the below steps to make sure your RV stays animal-free when not in use:

  • Check all your vehicle’s seals and seams and plug up those nooks and crannies with steel wool. Don’t forget your exhaust pipe.
  • Remove food, clothes, and valuables. If you need to store clothes in your RV over the winter, you can bust out the mothballs.
  • Check the floor for soft spots (a telltale sign of water damage). Step down hard around all the edges of your kitchen where the floor touches the cabinets. If you do find a soft spot, show it to your dealership or a professional immediately.
  • Leave your refrigerator and cabinet doors open to prevent mold and unpleasant odors. If you’re concerned about moisture, you can place a small dehumidifier in the main area of your RV.
  • Set a few mouse traps just in case.
Cleaning the inside of an RV fridge

How to Winterize Your RV Exterior

Before you put your rig away for the season, make sure the exterior is in tip-top shape. Here are the steps you can take when winterizing your RV exterior:

  • Give your vehicle a good wash and wax. Once it’s dry, spray your RV with silicone spray to waterproof it and take care of any leaks. Silicone spray works on plastic, wood, and metal surfaces.
  • Check the roof of your RV for any cracks, cuts, or holes where water might leak through and seal them with the proper type of sealant (consult with your RV manufacturer or dealer if you’re unsure). If your roof looks like it’s aging, coat it with liquid rubber. It is recommended that sealants be inspected yearly. 
  • Inspect vent caps, stink pipe vent covers, and air conditioner shrouds for damage or bird and wasp nests on the roof.
  • Inspect all the body seams of your RV, as well as the seals around the doors and windows. Check around air conditioners, TVs, vents, and other openings for any soft spots or discoloration. Open your overhead cabinets to check the top corner where the wall and ceiling meet. 
  • Inspect your water heater and furnace for any signs of water damage. Also, mark your calendar for another inspection in the fall. If you see actual water damage, take it to the RV dealer for a professional repair.
  • If your vehicle has an awning, use RV awning cleaner to clean it while removing any mildew. Don’t use dish detergent as that can dry it out.
  • Spray your doorway with a natural pest repellent. 
  • Close the vents to your furnace and water heater and install bug screens over them.
Man checking tire pressure

Storing Your RV for Winter

Once you’re done with your vehicle’s interior and exterior, it’s time to think about storage. First off, keep in mind that open-air storage can be unkind to your RV’s exterior. The best storage space is an enclosed steel garage where you can regulate the temperature. If you don’t have an enclosed garage space, your next best option is a covered steel structure that will protect your vehicle from the elements (but not freezing temps).

Once you’ve selected a storage space, here are the next steps:

  • Check your radiator hoses and clamps by looking for wear or soft spots. Replace them as needed.
  • Check your heater hoses and clamps. Replace them as required.
  • Remove the propane tanks from your RV. Top them off, then shut them off and store them in a separate safe location.
  • Check the air filter. That way, you’ll have clean air when road trip time returns.
  • Check all your lights, including your turn signals, headlights, and bright lights. Now is a good time to replace any burned-out bulbs.
  • Turn off the circuit breakers for electricity, heat, and air conditioning. 
  • Disconnect your battery and store it in a warm, dry place.
  • Remove weight from your tires by jacking up the axle and using support blocks so you can inspect them. Look at tread depth and casing quality and check the sidewalls for any weathering. If your tires have less than 6/32-inch tread depth, you may need to replace them to maintain safe traction and handling performance.
  • If tires look good, inflate them to correct pressure to avoid any flat spots and cover them with tire covers. 
  • Park your rig with the emergency brake on and use wheel chocks to keep pressure off your tires and your vehicle stable and in place.
RVs parked under a cover

Storing Your RV Outside in Winter

If you’re going to store your vehicle outside, cover it with an RV storage cover that’s made from a breathable material to keep mold and mildew from growing underneath it. Make sure that it covers any roof vents and windows. It’s important to understand how to order the proper size cover for your rig; you can check owner’s groups for recommendations. 

It’s not a bad idea to walk through your RV every few weeks in the offseason. Check the mouse traps and give things a once-over to make sure nothing is amiss.

Winterizing Steps for Motorcoaches

If you own a motorized RV, then you need to take some extra steps. Make sure you take care of any recommended maintenance based on your mileage and length of ownership.

  • Check for any fluid leaks; if you find one, get it repaired at your nearest RV service department. 
  • Top off your engine oil, transmission, steering, brake, and windshield fluids to prevent moisture build-up in the offseason. You can also top off the gas.
  • Add fuel stabilizer and pull into the engine and generator before storing.
  • Test your roof air conditioner and clean or replace the filter.
  • Check your refrigerator and all other appliances to make sure they’re working properly.
  • Test the charge, water level, cables, and connections of your auxiliary battery.
  • Check your accessories and 12-volt interior lights.
  • Make sure your generator works properly under load. Check the filters and service them per the manufacturer’s recommendations.
  • Check your fire extinguishers, smoke alarm, and your carbon monoxide and propane gas leak detectors.
  • Consult your owner’s manual for anything additional specific to your model.
Man and woman checking the engine of a motorcoach

The Most Common Mistakes Made with RV Winterizing

When winterizing your RV, take a moment to learn from the most common mistakes made by RV owners. 

  • Forgetting to put antifreeze in outdoor shower units.
  • Not closing low-point drains and wasting antifreeze.
  • Not adequately flushing water lines.
  • Forgetting to bypass the hot water heater before using antifreeze.
  • Forgetting to drain the hot water tank.
  • Not replacing the drain plug or anode rod on the water heater. 
  • Waiting too long to purchase antifreeze as supply can run short the closer you get to the winter months.

Winter RV Camping Tips

Winter camping is not uncommon and you can still use your rig in the winter in a variety of ways. You can camp in a winterized unit and just not use water. You can use tank heaters to keep the interior of your rig warm, which will prevent any freezing issues while camping—but if you unplug and travel, you better be prepared before you move. Some campers will put several gallons of antifreeze into their fresh water tank, allowing them to use the water pump to flush toilets. You can also use a Thetford Porta Potti as an alternative for bathroom needs.

Airstream parked at campsite with snow in the surrounding landscape

What You’ll Need to Winterize Your RV

Here’s a list of everything you might need to winterize your RV. You can find these items at most RV parts stores, hardware stores, or online retailers. 

  • 2 to 3 mousetraps
  • 3 gallons of non-toxic RV/marine antifreeze
  • Air compressor
  • Awning cleaner
  • Blow-out adapter
  • Breathable RV storage cover
  • Bug screens
  • Caulk and caulk gun
  • Dehumidifier (optional)
  • Holding tank flush wand
  • Jack stands
  • Mothballs
  • Silicone spray
  • Steel wool for any interior holes
  • Wash and wax cleaner
  • Water heater bypass kit
  • Water heater tank rinse wand
  • Water filter bypass hose
  • Water pump converter kit
  • Waterproof sealant
  • Wrench for drain plug or anode rod

When the weather warms up, you’ll be ready to hit the road sooner if you’ve properly winterized your vehicle. When that time comes, be sure to check out our guide on How to Dewinterize Your RV.


Rob Cochran

Rob Cochran is the Head of RV Service at Togo RV. With over 30 years in the RV service industry, he’s passionate about making life better for RV owners and technicians. He’s an RV Industry Association Master Certified RV Technician and the Education Chairman for the Florida RV Trade Association. In addition to working in the industry, Rob has been RVing since 1993, which is when he purchased his first camper.