How To Winterize a Class A RV – 15 Important Steps Plus A Free Checklist

Winterize a Class A RV
Photo by Giovanni Moschini on Unsplash

Many Class A RV owners store their motorhomes in climate-controlled environments or move them to warmer climates during the winter. If this is not an option for you and you need to winterize your Class A RV, there are special steps needed for Class A RVs.

Not following a winterizing plan specifically designed to winterize a Class A RV could cost you a lot of money in repairs. Read on to learn how to make sure your Class A RV is winterized correctly to avoid damage.

How To Winterize a Class A RV – Skipping These Steps Can Cost You!

To winterize a Class A RV, you must take all the usual steps of draining tanks and water lines, but you also have to follow special procedures for each expensive amenity you have on your motorhome. The following Checklist provides the details you need to Winterize a Class A RV.

Winterize Your AquaHot and Aqua View Systems

Hydronic heater systems (AquaHot), water reclamation systems (Aqua View ShowerMi$er), and Reverse Osmosis Water Filtration systems all require special care to avoid damage due to improper winterization.
No insurance or warranties cover weather-related damages.

Want a free RV winterizing checklist pdf? Click the link for a Checklist of Steps You Must Take to Winterize A Class A RV.

Why You Should Winterize A Class A RV

Class A RVs are equipped with sophisticated systems throughout the chassis, and one burst pipe can cause significant damage and be very expensive to repair. Damages due to weather and improper winterization are not covered under insurance or any warranty.

At what temperature should you winterize a Class A RV?

You should winterize a Class A RV any time temperatures are forecast to be below 32 degrees Fahrenheit or 0 degrees Celsius.

Pay attention to weather forecasts and get your RV winterized before the first freeze, otherwise, you may find it is too late.

RVs in Warm Climates May Need Winterizing

Most people don’t know that any time you plan on storing your RV for longer than 30 days, you should winterize the motorhome. This assures that the plumbing and appliances are protected against damage.

Even if your RV is going to be stored in a warm climate, draining water lines and flushing with antifreeze lubricates seals and helps protect you from further damage should a leak happen.

Do you have to use antifreeze to winterize a Class A RV?

Yes, in addition to draining your RV water lines and using an air compressor to blow the residual water out of the plumbing lines, you should take the extra step of flushing RV antifreeze through your systems.

Even a small amount of water, once frozen can cause big damage to expensive RV systems.

What is RV Antifreeze?

RV antifreeze is a special non-toxic product designed specifically for RV and marine plumbing systems and is PINK in color. It is not the same thing as automotive antifreeze.

DO NOT USE AUTOMOTIVE ANTIFREEZE in your RV water systems, it is toxic and you will contaminate your water systems!

Types of RV Antifreeze

There are three different types of RV antifreeze available, but only one is suitable for your RV.

Two WORST RV types of antifreeze that you Should Not Use

  • Ethanol (alcohol) Based Antifreeze – This is the stuff you find at most hardware and discount stores. This type is the lowest cost, but don’t be fooled into purchasing it. It can taint your RV plumbing systems and leave your water tasting or smelling bad even after you flush your systems.

    Additionally, the alcohol will dry out the rubber seals in your faucets and toilets. So while your plumbing lines may not be broken, they still may leak around the seals.

    It is also highly flammable and should not be used around pilot lights.
  • Propylene/Ethanol Blend Antifreeze – Since this is an alcohol blend, it can also make your water smell and taste bad.

    It will also dry out your plumbing seals allowing leaks.

    Since it has alcohol in it, it is also flammable.

ONLY USE RV Antifreeze made of Propylene Glycol

  • Propylene Glycol Antifreeze is non-toxic and is the safest for all types of RV plumbing. It’s non-flammable and does not taint water systems. Propylene glycol is a lubricant and will actually work to extend the life of the seals in your toilets and faucets.

    The most popular brand is Camco and it’s available in -50 and -100 freeze burst protection.

How many gallons of antifreeze do I need to winterize a Class A RV?

The amount of RV antifreeze you will need to correctly winterize a Class A RV depends on the size of your motorcoach. We have a 44-foot Newmar Mountain Aire Class A RV and the manufacturer recommends that we have 7 gallons of RV antifreeze available to properly winterize our RV.

It’s better to have more antifreeze than you need than not having enough. Antifreeze is inexpensive compared to the cost of repairing damage to your RV plumbing systems!

What Do You Need To Winterize A Class A RV?

  • Air Compressor and pressure regulator set to a maximum of 30 psi
  • 7 gallons RV Antifreeze
  • Window washer fluid with antifreeze
  • Teflon tape (for hot water heater anode)
  • Fuel Stabilizer
  • Full Fuel Tanks
  • Automotive Antifreeze (for your RV engine ONLY)

What are the Major RV Systems You will Winterize?

  • Water System
  • Water Heater
  • Drains and Tanks
  • Appliances
  • Generator
  • Batteries
  • Awning
  • Roof
  • Tires
  • Exterior
winterize a class a rv

Checklists of Steps You Must Take to Winterize A Class A RV

There are basically 4 major parts to winterizing a Class A RV this also includes how to winterize a diesel motorhome:

  1. Preparation
  2. Draining the water
  3. Blowing out the Lines with an Air Compressor
  4. Flooding the lines with Non-Toxic RV Antifreeze.

These checklists assume that AC power is not available and you are not storing your RV in a climate-controlled storage area.

Tip: A few of the steps are easier to do if you have a partner helping you.

*Our Checklists for Winterizing A Class A RV are meant to be a tip sheet. Appliances, drain locations, and plumbing components vary by coach. Please consult your owner’s manuals for further detailed information.

Tip: You may want to print out our checklists and make notes specific to your Class A RV winterization process.

Preparing to Winterize A Class A RV:

Download Preparation Checklist

  • Get your supplies ready first, before starting your winterization.
    • Purchase RV Antifreeze, Window washer fluid with antifreeze, Automotive Antifreeze- FOR YOUR RV ENGINE ONLY, Fuel, and Teflon tape.
    • Make sure your air compressor is in good working order and you have a pressure regulator set to a maximum of 30 psi.
  • Fuel-
    • Before you begin your RV winterization, top off your RV fuel tanks and add a fuel stabilizer. Storing your motorhome with a full tank of fuel will minimize moisture condensing at the top of the tank.

      In fact, this is a great habit to get into every time you return from your latest RV adventure. Diesel fuel is an organic material that can develop microbial growth called black algae. Fuel stabilizers control microbe growth and degradation of the fuel.
  • Location-
    • If you cannot find a facility that provides shore power while storing your RV, find a paved or concrete surface to park. Park your motorhome as level as possible. Do not store with the slides open.
    • Avoid parking your RV on a grass or gravel surface to prevent moisture accumulation under your motorhome and to prevent tires from sinking into the ground during the thaw. BE SURE TO SET YOUR PARKING BRAKE.

      Tip: If possible, position your motorhome so the house and chassis batteries are accessible without having to move your RV.
  • Tires-
    • Check your tire pressure. It’s best to store your RV with tires at maximum inflation as recommended by your tire manufacturer to prevent damage caused by under-inflation.
    • Tire manufacturers recommend getting the weight off your RV tires if possible. Lower your jacks to help take the pressure off of the tires and if you are not on a paved surface, place boards under the tires.
    • Cover your RV tires to prevent sun damage and cracking.
  • Shut off all Appliances
    • It’s best to turn off the breakers too in addition to the power switches.
  • Disable Auto Genstart
    • Consult your owner’s manual for instructions.
  • Batteries
    • When storing your RV make sure the house and chassis batteries are fully charged. Batteries stored in a discharged state will readily freeze and damage the battery.
  • Remove all Food and Beverages
    • Clean out your RV refrigerator, freezer, and cabinets of all food and beverages. Canned foods or bottled drinks can freeze and burst. In addition to causing a mess, it will attract pests and rodents. Even packaged goods should be removed to keep any hungry critters from making meals in your motorhome!
  • Propane Gas
    • Turn off propane gas at the tank.
  •  Roof
    • Close all roof vents
    • Cover all air conditioning units
    • Don’t let snow accumulate on the roof
  • Close shades and curtains
    • To protect your interior fabrics from fading, close all window treatments.
  • Windshield Wiper/Washer
    • Remove your windshield wiper blades and store them inside your RV.
    • Top off your window washer tank with window washer fluid with antifreeze
  • Solar Power
    • If you have a solar battery charger, the battery disconnect switch must be ON to allow the solar charger to provide a trickle charge to your house and chassis batteries.
  • Satellite Dish and Antennas Down
    • Make sure all external antenna and satellite dishes are stored in the down (travel) position.
  • Regular Inspections
    • Arrange to have someone check on your RV, both inside and out every couple of weeks to look for leaks or damage.

Draining the Water from Your Class A RV

Download Draining Checklist

  • Water Tanks
    • Disconnect the outside water source, turn off your water pump and open every low point drain
    • Flush and drain your black and grey tanks
    • Drain your fresh water tank with the low point drain valves (one for hot and cold)
    • Go inside and turn on the faucets to make the water drain faster
    • Flush all toilets
    • Turn off power switches and breakers for the water heater or hydronic heating system
    • Turn off the refrigerator power switch
    • While tanks are draining, remove all water filters (including the main one in your wet bay and any inline, under sink, and refrigerator filters –very important)
    • Reattach the main water filter canister and all water filter plugs from the filters you removed (so that the antifreeze doesn’t leak out)
  • Reverse Osmosis System (if you have one)
    You need to get the water out of your reverse osmosis water system because if it freezes it will destroy the unit.

    I checked with the industry expert, Dave at the RV Water Filter Store and he recommends these steps:
    • Drain the unit
      • Remove the filters
      • Remove the membrane and put in a zip lock bag to keep it from drying out
      • Store it in your home refrigerator to keep bacteria from growing
  • Water Heater
    • You must drain your hot water heater during winterizing a Class A RV- Never drain it while under pressure or when it is hot!
    • Open the hot water heater relief valve. Be careful it doesn’t spray water in your face!
    • Remove the drain plug which is probably an anode
    • Once drained, place fresh Teflon tape on drain plug threads and carefully replace it by screwing on by hand first and then using a wrench while making sure not to cross-thread. If you cross-thread your drain plug it will leak.
    • Go to the wet bay and turn the valve to bypass your hot water heater so antifreeze doesn’t go through it.
  • Tankless Water Heaters
    • DO NOT put the water heater in by-pass mode. Instead, blow it out, and install the antifreeze as directed for a hydronic heater.

      Aqua-Hot Hydronic Heater- Courtesy of Aqua-Hot (more info is available on their website)
      According to Aqua-Hot, not winterizing the Aqua-Hot when freezing temperatures are present will result in SERIOUS damage to the Aqua-Hot’s Domestic Water Heating System. Also, be sure to use only FDA-approved, RV antifreeze.
      Please follow these instructions carefully when winterizing the Aqua-Hot’s hot water heating system:
      • Completely drain the fresh water storage tank.
      • Disconnect the domestic water demand pump’s suction line from the freshwater storage tank.
      • Attach an adequate piece of hose onto the suction side of the domestic water pump.
      • Place the opposite end of the hose into an adequate supply of the RV antifreeze and allow it to pump through the system.
      • Open and close all interior and exterior water faucets, one at a time, until ONLY pure RV antifreeze is present. Perform this procedure for both hot and cold faucets.
      • Remove the hose from the RV antifreeze and reconnect the domestic water demand pump’s suction line to the freshwater storage tank.
  • Fresh Water Reclamation System
    Since several RV manufacturers offer the Aqua View SHOWMI$ER, I am including the instructions from their website. If you have a different brand, I suggest you contact the manufacturer for specific instructions.

    The important point is DON’T FORGET that the Fresh Water Reclamation system requires winterization too!
    Courtesy of Aqua View SHOWMI$ER website:
    • Cycle the valve to the bypass position to purge the water out of the line back to the fresh water tank while the pressurized air supply is connected.
    • Then place the valve back to normal flow mode to the showerhead, and then purge the shower.
    • Do not leave the valve in bypass mode when running antifreeze in the line because it will allow antifreeze into the fresh tank.
  • Refrigerator- this takes two people
    • Assuming you already emptied the contents of your refrigerator in the step above, turn the Fresh Water Valve off
    • Outside- unhook the freshwater supply and drain
    • Inside- use a cup to drain the residual water and ice from the water dispenser
    • Make sure that all refrigerator water filters are removed and the plugs in place
    • Empty the ice maker
    • Prop your RV refrigerator doors open using a towel or other method to avoid mildew
  • RV Dishwasher Winterization
    • Run a short cycle to drain all the water out and make sure there is no residual water in the tub.
    • You will flush antifreeze through your dishwasher in the steps below.

Blowing Air Through Your RV Systems

Download Air Checklist

The next step in RV winterization is to use your air compressor to blow air through your motorhome systems to remove any residual water. Remember that any water remaining in the lines will dilute the antifreeze and require more antifreeze to properly protect your lines.

Even a small amount of water, once frozen, can cause major damage to your RV!

Tip: Make sure your air compressor has a regulator and it is adjusted to no more than 30 psi so that you don’t damage your water lines!

Clearing Your RV Water Lines with an Air Compressor

  1. Connect the regulated air supply to the inlet of the hose from the hose reel (if equipped) or the city water fill inlet. Air will flow out of the low point drains.
  2. Open all faucets and showers (both inside and out) and the auto-fill or tank fill valve (whichever your RV has) to all possible positions for a minimum of 10 seconds at each position. Do not forget the outside shower and any additional outside water spigots.
  3. Cycle the tank fill valve to all positions in order to purge water out of the lines and valve assembly.
  4. Flush your toilets.
  5. When no more water is coming out, close all valves and faucets including showers.

Flushing Non-Toxic RV Antifreeze through Your RV

Very Important Tips-

Make sure that you have your freshwater tank bypass valves set correctly because you DO NOT want to flood your freshwater tank with antifreeze!

Make sure you have your hot water heater bypass valve in the correct position so that you do not fill your hot water tank with antifreeze. It’s a waste of antifreeze and not necessary.

Make sure ALL of your water filters have been removed (including the refrigerator). Reinstall your water filter canister minus the filter and all water filter plugs. If you don’t, you will waste antifreeze, make a mess and ruin your water filters!

How to get antifreeze into RV lines

Download Flushing Checklist

  • After blowing the water out of the system with pressurized air, disconnect the hose, and pour approximately one cup of antifreeze into the hose. Hook the hose back up to the pressurized air, and blow the antifreeze through the hose and hose reel to protect it.
  • Close the low point drains. This must be done prior to pumping antifreeze through the lines, or the antifreeze will be pumped onto the ground.
  • Remove the whole house filter canister, dump any remaining water, and reinstall.
  • Winterizing valves in the wet bay are generally unique to the model and year of your motorhome. Make sure yours are in the correct winterizing position.
  • Insert the winterizing hose into a jug or bucket of RV antifreeze.
  • Turn on your water pump to draw the antifreeze into your water lines. Pink antifreeze will start flowing through the clear hose into the water lines. Make sure you are checking the supply of antifreeze and replenishing the bucket as needed to complete the entire process.
  • Go inside and turn on the cold water from the kitchen faucet and run until the pink antifreeze comes out and then turn it off. Repeat this with the hot water faucet.
  • Proceed to the next faucet, and repeat the process for each faucet, including the lavatory, shower sprayers, and outside shower faucet. If equipped, repeat the process for the instant hot water, drinking water dispensers, and hot water spigot with a low point drain (next to the generator).
  • Flush each toilet until the pink antifreeze is detected. If the toilet is equipped with a sprayer, activate and flush it until the antifreeze flows from the sprayer.
  • After you have finished and closed all valves inside and out, go inside and pour a cup or so of antifreeze into each sink to make sure to fill each P-trap.
  • Pour antifreeze into each toilet and allow it to remain in the bowl without flushing. This will help lubricate your toilet seals.

    Tip: RV Antifreeze will stain! Be sure to clean up as you go and don’t let it dry on any surface!

RV Refrigerator Winterization

  • Depress the refrigerator’s external water dispenser while holding a container to catch the fluid. Continue to let the fluid flow until the pink antifreeze is detected.
  • The pink antifreeze may not appear instantly, as most refrigerators have a reserve for cold water. However, if you did not remove the water filter as previously instructed, the fluid will run clear for a long time and you will have ruined your filter.
  • Make sure the ice maker is turned on. Once it reaches the proper temperature, it will attempt to make ice cubes, which will become pink in color. This may take several hours. Once they become pink, turn off the ice maker and the refrigerator. Empty the ice cube tray, and clean out the ice maker and freezer area.

RV Washer Winterization

The winterization procedure you follow for your RV washer depends on the brand of washer that you have in your motorhome. I’ll cover the 2 most popular, Splendide and Whirlpool with instructions directly from their websites.

You should always consult the manufacturers’ website for models specific to your RV.

Splendide Washer Winterization courtesy of their website:

  • With the machine power OFF, turn the WASH TEMP knob to HOT
  • Advance the Program Selector knob to REGULAR in Cotton Heavy Duty
  • Press the ON/OFF button (IN) and let the machine fill until antifreeze is in the drum
  • Advance Program Selector to a RESET. Wait 5 seconds (Status/Door Lock LED will blink)
  • Advance Program Selector to a SPIN position. Let the antifreeze drain from the drum
  • Advance Program Selector to RESET. Wait 5 seconds (Status/Door Lock LED will blink)
  • Turn the WASH TEMP knob to COLD
  • Advance the Program Selector knob to REGULAR in Cotton Heavy Duty
  • Let the machine fill until you see antifreeze in the drum
  • Advance the Program Selector knob to RESET. Wait 5 seconds (Status/Door Lock LED will blink)
  • Advance the Program Selector knob to SPIN. Let the antifreeze drain from the drum
  • Press the ON/OFF button (OUT).

Whirlpool RV Washer Winterization courtesy of their website:

  • Put 1 quart (1 liter) of RV antifreeze in the drum.
  • Run washer on a Drain/Spin cycle.
  • Unplug the washer or disconnect the power.
  • Shut off both water faucets.
  • Disconnect water inlet hoses from faucets and drain.

Class A RV Winterization Complete

Remember that all luxury RVs have different systems and you should make a list of what systems water flows through on yours. It doesn’t matter whether you decide to do this yourself or hire a professional RV service center, it’s a good practice to have the list!

Good Luck with your RV Winterization, and one final tip that we use to winterize our Class A RV… we just drive it south to Florida for the winter!

Need to De-winterize a Class A RV? Read this article about how to De-winterize A Class A RV it includes a free complete checklist.

Do you have to winterize a Class A motorhome? Yes, if the Class A motorhome is going to be in cold climates or left unattended for long periods you should winterize.

How much antifreeze is needed to winterize a Class A motorhome? Approximately 10 gallons of antifreeze is required to winterize a Class A RV. It may take more if the motorhome has many systems that use water.

How much does it cost to winterize a Class A RV? If you do it yourself, it costs about $150 to winterize a Class A RV. You can hire RV maintenance companies that will do this for you.

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