Tips & Guides

How to Winterize an Airstream Touring Coach


If you aren’t a four-season traveler, or you live in a colder climate during the winter months, preparing your Airstream Class B for winter is an important step.

It’s always important to consult your manual before you do anything with your unit, but here are some steps to drain the water out of your unit and to winterize it for the colder months.

If you would rather have a professional winterize your unit, any authorized Airstream dealer can assist you with this. For those of you who want tackle this on your own, we’re sure you’ll find the step by step instructions below easy to follow.   

Do I need to winterize my Airstream Touring Coach?

If you’ve ever known someone or had the unfortunate circumstance of being the SOMEONE, who has had a pipe burst in the middle of winter, you understand the importance of making sure that your plumbing is ready for the colder weather.

The same is true for your Airstream Touring Coach built on the iconic Mercedes-Benz® sprinter chassis. One of the most important steps of winterization for your sprinter RV is to make sure that your pipes do not freeze by flushing all of the water out of the lines.

Beyond that, there are some tips and house-keeping best practices, that will help your coach be ready for new adventures once the weather warms up again.

The first step is to determine how much winterization you need to do. Many owners “winterize for use,” by blowing out all the water and maybe cycling RV antifreeze through the system – and continue to use their Airstream throughout the colder months. Others will store their Airstream and not use it until spring. If storage during the winter months is your plan, then the full winterization regimen should be followed.

Step 1: Leveling your unit

Ensure that your coach is level. This will allow the fluids to drain properly from your van, as well as being safe during the entire process. You will want to ensure the coach is level from side to side as well as front to rear. Turn the water pump off, and disconnect the city water from your RV.

Leveling your Airstream Touring Coach
Level your Airstream Touring Coach

Step 2: Open the faucets

Open the hot and cold-water faucets throughout your Airstream touring coach. It’s important that both hot and cold are turned on to ensure that the system has been fully drained.

Step 3: Drain the Water Tank and Water Heater

Airstream Atlas

Open the fresh water tank drain valve and water heater drain valve. The fresh water tank drain valve is located under the touring coach in front of the roadside wheels.

You will need to remove the service panel on the back of the water heater to access the drain valve for the water heater. The water heater is located under the galley and accessed by removing the galley drawers.

If a level surface is not available, park the touring coach facing slightly uphill until water draining ceases and then downhill until water draining ceases.

Airstream Interstate

Open the fresh water tank drain valve and water heater drain valve.

There are four fresh water low point drain valves. Two are located, depending on model, under the galley accessed by removing the drawer below the microwave or below the refrigerator accessed by removing the vent below the refrigerator. Two more are located under the curbside lounge accessed by removing the cup holders.

On twin bed models the two are located under the curbside bed accessed by lifting the mattress. The fresh water drain plug is located on the front of the fresh water tank under the touring coach. The water heater drain valve is located on the water heater under the curbside rear lounge or bed, and accessed by removing the service panel.

If a level surface is not available, park the touring coach facing slightly uphill until water draining ceases and then downhill until water draining ceases.

Coach Gravity Drain
Locate and open the low point drain valves

Step 4: Winterizing the Toilet

Turn off the touring coach’s water supply, drain the toilet bowl completely, and disconnect the supply line at the water valve. To avoid damage when using air pressure to blow water from the lines, make sure the toilet valve is in the open position. *If water is frozen in the toilet, do not attempt to flush until the ice thaws. While the water is draining from the systems remove, drain, and store the wet bath and the exterior shower hoses and shower heads.

Step 5: Blowing out the Water

After the water has stopped running, apply at most 30 lbs of air pressure at the city water inlet. This can be accomplished at a service station if no air compressor is available. Air fittings with regulators for the city water inlet can be purchased at most RV stores and also online at the Airstream Supply Company.

Be sure the toilet flush valve, toilet shut off valve, all drain valves, and all faucets are open and the pump outlet hose is disconnected. Up to 50 lbs of air pressure can be accomplished only if the water heater bypass valve has been set to its bypass position. If more than 30 lbs of pressure is used on the water heater, damage could occur.

Air Compressor at City Water Inlet
Connect and air compressor to the city water inlet

Step 6: The Water Pump

Remove the quick-connect outlet fitting from the pump and turn the pump on briefly to pump out any remaining water from the pump head and lines.

Check the water pump strainer to be sure no water remains. There should be very little water if the tank has been drained. Be sure to have a catch pan or a rag under the pump to prevent water from spilling into the touring coach. Leave the fittings disconnected from the pump until the system is ready to be used again. Leave a note on the water pump switch that the plumbing is not connected.

RV Antifreeze

An optional, but not necessary, method for winterizing protection, is to add a non-toxic antifreeze (approved for drinking water system) to the water lines using the following procedure:

  1. Reconnect all lines except the one to the pump inlet port and close all drain valves.
  2. Turn the water heater bypass valve to its open position, see diagram below. The valve in the Airstream Atlas is located under the galley accessed by removing the drawers and in the Airstream Interstate the valve is located under the rear lounge on the curbside of the coach.
    Valve Positions
  3. Attach a length of hose to the water pump inlet port. This piece of hose should be long enough for the free end to be inserted into and reach the bottom of an RV, non-toxic antifreeze container.
  4. Check that all interior water faucets are still open.
  5. Insert the hose into the container containing, RV, non-toxic antifreeze, turn the pump on, and run the water pump until the RV, non-toxic antifreeze solution fills all water lines and flush the toilet.
  6. Open the exterior shower faucet until RV, non-toxic antifreeze comes out of the hose, shut off the valve, and remove the drain valve/hose assembly.
  7. Close the water fixtures as the RV, non-toxic antifreeze begins to come out. Shut off the pump when RV, non-toxic antifreeze has been distributed throughout the system, and then reopen all faucets to relieve pump pressure.
  8. Disconnect the hose length from the pump inlet fitting, and reconnect the water system inlet line.


Additional Tips for Winterization

Water Heater Winterization

If the touring coach is to be stored during winter months, the water heater system must be drained to prevent damage from freezing. Once drained, RV non-toxic antifreeze can be added.

  1. Turn off electrical power to the water heater by using the water heater’s control panel, located above the lavy sink for the Airstream Atlas or on the Multiplex touch screens in the Airstream Interstate, or by removing the fuse.
  2. Shut off the gas supply to water heater.
  3. Turn off the water pump.
  4. Open both hot and cold-water faucets.
  5. Remove the water heater’s service panel to access the drain valve. In the Airstream Atlas, the water heater is located under the galley and accessed by removing the galley drawers. In the Airstream Interstate it's located under the lounge or bed for twin models on the curbside.
  6. Turn the drain valve knob clockwise to drain and then clockwise again to close.
    *The system will need to be refilled with water and all air removed from lines before the unit will re-light.

Black & Gray Water Tank Winterization

Plan your winterizing and storage ahead, and be sure the holding tanks are drained and flushed thoroughly. This is very important, as the frozen sewage and water could seriously damage the system.

After dumping the tanks, add a quart or two of RV, non-toxic antifreeze to one of the holding tanks and start the macerator pump. Run the pump until the RV, non-toxic antifreeze comes out the end of the pump hose. Leave the dump valves open.

As extra protection, open the toilet valve and add a quart of RV, non-toxic antifreeze to the Black Water tank and into a sink drain to protect the holding tanks, valves, and pump.

Removing the Battery for Winter

Remove the house batteries from your touring coach and store in a cool dry place where there is no danger of freezing.

It is very important for optimum life of your battery to check it periodically and to keep it fully charged. This is especially true in winter months, when the temperature may drop below freezing. If the period of storage is for 30 days or less, you may turn off the battery disconnect switch rather than remove the battery. Continue to check and recharge the battery as needed, at least weekly in severe weather.

Winterizing your Airstream Touring Coach is a vital part of ownership. Keeping the coach in good working order and preparing it for colder climates is essential to enjoying your Airstream Touring Coach for years to come. You can also watch this helpful video on how to winterize your Airstream Touring Coach.

Always consult an Airstream technician or Airstream Customer Service for specific questions regarding this process or any other maintenance you might attempt.

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