How to Winterize a Camper

Learn how to winterize your RV or camper to protect it from the freezing conditions of winter and prevent expensive repairs down the road.

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With winter just around the corner, you’re probably starting to think about retiring your coach for the year. Unfortunately, failing to properly “winterize” your RV or camper can result in broken pipes, frozen water heaters and other damage that could require (often expensive) repairs. To avoid that headache, follow this guide to prepare your RV for winter so you won’t encounter any unpleasant surprises next spring.

Required Supplies

Before you start, acquire the necessary supplies. They’re relatively inexpensive and easy to use. Your RV might already have some of them, so consult your owner’s manual to determine whether you need to purchase the indicated items.

The winterizing process requires basic tools and supplies such as:

  • One to three gallons of RV or marine antifreeze (usually pink). The exact amount depends on your RV’s plumbing system layout, but a few gallons is usually enough. Conventional automotive antifreeze is toxic and can’t be used for winterizing.
  • A winterizing kit (also called a “water pump bypass”) if your RV lacks a factory installed winterizing system.
  • A water heater by-pass kit if your RV doesn’t have one.
  • RV sewer hose.
  • Tools for accessing and removing drain plugs, usually a socket wrench and screwdriver (handheld or battery powered).
  • Optional: Spray wand for cleaning the black water tank.

Drain the Gray and Black Water Tanks

Draining the gray and black water holding tanks prevents two things: The buildup of nasty bacteria from stagnant waste water, and a frozen tank filled with standing liquid.

To drain your holding tanks:

  1. Take your RV to an approved dump station, attach your sewer hose and run it to the station’s sewer inlet.
  2. Start with the black water tank and slowly open the corresponding valve handle (usually black) until it drains out completely.
  3. As an optional step, you can give the black water tank a more thorough cleaning with a spray wand.
  4. Drain the gray water tank by pulling open the corresponding valve handle (usually gray) until it drains out completely. It’s suggested to drain the gray water tank last so the cleaner liquid can wash away any residual material from the black water tank.
  5. Clean out, disconnect and put away your sewer hose. Now you’re ready for the next step

Drain the Water Heater

Replacing a frozen water heater can be costly, so it’s important to thoroughly drain your water heater.

  1. Make sure the water heater is off, cooled down and depressurized. If not, you could burn yourself when the hot, pressurized water sprays out of the water heater’s drain.
  2. Remove the drain plug or anode rod with an appropriate socket or wrench.
  3. Open the pressure relief valve for optimal drainage.
  4. Once it stops draining, reattach the drain cap or anode rod and proceed to the next step.

Here’s how to drain your RV water heater to make sure it operates safely and efficiently.

Gettyimages 972083844Ricky Kresslein/Getty Images

Bypass the Water Heater

Bypass your water heater. If you don’t, you’ll use too much antifreeze (six to 10 gallons, depending on your water heater’s capacity) and may find antifreeze coming out of your shower and sink lines next year.

Your RV’s water heater might have an integrated bypass system. If not, you’ll need to purchase and install one. You can get a seasonal bypass kit that’s installed over the winter and removed the following spring, or a permanent bypass kit designed to stay on your hot water tank. Both are relatively inexpensive and easy to install.

Once the bypass has been located or installed, open the bypass valve and close the water heater’s supply line valves. Follow the instructions from your purchased kit or your RV’s owner’s manual for your unit’s specific procedure.

Drain the Water Lines

Along with the water heater, you need to completely drain all your RV’s plumbing lines to prevent any residual liquid from freezing and breaking the pipes.

  1. Find the low-point drain lines. Your hot water, cold water and freshwater lines all need to be cleared, and there is usually (but not always) one drain for each system. They can all be found underneath your RV. Consult your owner’s manual if you can’t find them.
  2. Remove the drain caps or open the valves and allow them to drain completely.
  3. Remove the remaining water by turning on all the sink faucets and shower valves (inside and outside) and flush the toilet until water stops running.
  4. Close the drains by reinstalling the caps or closing the valves.
  5. Now remove any inline water filters to prevent damaging them in the next step. While you’re at it, inspect the filters to see if they need to be replaced.

Add Antifreeze

Now it’s time to add antifreeze to your RV’s plumbing system. Flooding the plumbing lines with antifreeze will ensure that nothing freezes and breaks over the winter.

  1. Ensure that the fresh water tank’s inlet valve is closed to avoid filling up your freshwater tank with antifreeze. Thankfully, this valve is usually near your winterizing hose.
  2. Using your RV’s factory-installed winterizing system or an aftermarket winterizing kit, place the winterizing hose into one of your jugs of antifreeze and turn your water pump on.
  3. The water pump will start sucking up antifreeze as it fills the RV’s plumbing lines. Replace the jugs of antifreeze as they become depleted.
  4. Follow the same procedure you used to drain the water from the lines. Turn on the hot and cold sinks, turn on the shower (indoor and out) and flush the toilet. Keep everything running until you see colored antifreeze coming out. Then shut off the valve or stop flushing the toilet.
  5. Pour about a cup of antifreeze down the sink and shower tub drains to fill the plumbing traps. This will prevent any remaining water in those traps from freezing and breaking those pipes.
  6. Wipe off any residual antifreeze in the sinks and tub to prevent possible staining.
  7. Go outside to your 3/4-inch garden hose connection (the “City Water” inlet) and remove the filter screen with your hand or a flat-head screwdriver. Locate the nipple (usually white) just inside the inlet. Using your finger or the tip of a screwdriver, apply pressure to the nipple until antifreeze starts spraying out. It’s best to stand off to the side when doing this to avoid getting sprayed with antifreeze.
  8. Turn off the water pump once all the lines have been filled.

Additional Winterizing Steps

The plumbing in your RV is the most important system to protect from winter, but there are several other important components to address. Take the following steps to comprehensively winterize your car.

  1. Clean: Remove any food products that can spoil or attract rodents seeking winter refuge in your cozy coach. You should also thoroughly clean your refrigerator to prevent any nasty, smelly surprises in the springtime.
  2. Protect your tires: Cover your tires with a UV reflective cover to prevent sidewall damage from the sun. You may also consider jacking your RV off the ground to remove the several tons of pressure from your tires.
  3. Protect your battery: Disconnect the battery and bring it indoors. Lengthy exposure to cold weather can permanently damage or destroy your RV battery, especially if it’s not in use. Hook it up to a trickle charger to give it a full charge prior to storage. If you don’t, sulfation can occur and cause permanent damage.
  4. Check the roof for leaks: A leaky roof can cause considerable damage that’s difficult to repair. Identity any possible sources of leaks and make necessary repairs.
  5. Check the seals around your doors and windows: Compromised weather stripping around your doors and dilapidated window sealing can allow moisture inside your RV. Check the integrity of these seals and make any necessary repairs.

Once you’ve completed all these steps, you’ve successfully winterized your RV and can rest assured it will be ready to go when spring returns.

James Fitzgerald
James Fitzgerald is a handyman and freelance home-improvement writer with a passion for DIY, gardening, and anything involving working with his hands. He has over a decade of professional experience in a variety of trades, including construction, tree work, landscaping, and general maintenance. When not in search of the next enticing DIY project, he may be cooking, lifting weights, riding his motorcycle, hiking out at the coast, or nose deep in a great book.