This is a repost of one of our previous blogs. Why? Because winterizing is starting now, not only up in the northern states, but in the south as well. Many folks are worried about having another “Texas Freeze” and have already started taking precautions. I want to preface this post by saying that I used compressed air to blow out my lines last year and had no ill effects of the “Texas Freeze”. That being said there is no safer way to winterize than using RV antifreeze. So if you have wondered whats involved in getting your trailer prepped for winter; here is how we winterize our travel trailer. 

Winterizing your travel trailer doesn’t need to be intimidating.  In fact it is a relatively straight forward process for anyone with basic mechanical skills.   Knowing how to winterize a travel trailer will not only save you a lot of time, but money too.  The cost, depending on which process you follow will probably be under $10.00.  If you decide you would rather have a dealership perform this service it will probably cost you at least $125.00.

I have been winterizing my own travel trailers since 1990, and have never had an issue.  Dealerships will tell you that they offer a warranty on their work.  So if they perform the routine and you have a problem in the spring, they will cover any damage that results from not having winterized it correctly.  I have no idea if they really would cover any damage, or if they would try to somehow blame the owner. Regardless, there is no shame in having a dealership winterize your unit; you need to do what allows you to sleep at night.

Today we will step through the process of how to winterize a travel trailer.  Please remember that every travel trailer is different due to different features and setups.  This article is not meant to be the Bible on your travel trailer.  You need to be familiar with your specific travel trailer model and consult your owner’s manual when in doubt.   Think of the following list as a generic version of what you will need to complete to avoid the off-season temperatures.  ALWAYS consult your own travel trailer owners manual for detailed information on winterization.  Each manual should cover the procedure.

Most importantly, once you know how to winterize a travel trailer;  the process is easily transferred to any new RV you purchase with minor changes to the process.  So make notes and create your own check list as you winterize, then you will have a great document you can use each year.

There are two different processes for winterizing a travel trailer.  One process is to fill all the water lines, and P-traps (drains) on the travel trailer with RV Antifreeze.  The second process is to blow out all the water lines with compressed air and then add RV Antifreeze to the P-traps.  You should decide on which process to use based on your climate.  If we were still living in Wisconsin, I would fill all my lines with antifreeze.  Here in Texas, I blow my lines out.  I’m sure there are people in the northern states that feel perfectly comfortable blowing their lines out.  I don’t think I could feel comfortable doing that.

So what are you going to need?  It depends on the process.  If you are blowing out your air lines you will need the following:

  1. Air Compressor that can deliver 40 PSI.
  2. Blow out plug (see picture below).
  3. Wrench for removing the water heater drain plug and any low point drain plugs.
  4. Screw Driver (probably an RV square head #2 screw driver) for removing any panels to access the water heater by-pass
  5. 1 Gallon of RV Antifreeze (to pour down each drain and in toilet bowl).

If you are running antifreeze through the water lines instead of blowing them out; you will need:

  1. Wrench for removing the water heater drain plug and any low point drain plugs.
  2. Screw Driver (probably an RV square head screw driver) for removing any panels to access the water heater by-pass.
  3. 3 Gallons of RV Antifreeze (to run through the water lines and pour down each drain and in toilet bowl).
How to Winterize a travel trailer:  The Process:

Step 1)  Make sure the Black Tank and the Grey Tank(s) have been emptied and rinsed out.  Pour your preferred tank treatment into the black and grey holding tanks.

Step 2)  Verify before you start,  that the propane and electric is turned off to the hot water heater.

Step 3)  Drain the water heater and leave the drain plug out.  Never drain the hot water heater when it is full of hot water or under pressure.  Make sure you open the pressure relief valve when you drain the water heater so that it drains completely.

Water Heater Drain Plu
Water Heater Drain Plug

Step 4)  Next rinse the hot water tank and allow it to drain.  You can buy a wand for rinsing your water tank on-line for a few dollars.  Insert the wand into the tank where you removed the drain plug.   Rinsing the water tank is not only a good idea before you store your RV but during the camping season.  Old water that is left in the water heater can produce nasty odors which are sometimes hard to eliminate.

Step 5)  Open the low point drains on your trailer.  The purpose of opening these drains is to empty the water lines.  Keep in mind, this will not completely empty the lines.

Low Point Drains
Low Point Drains

Step 6)  Open the drain valve on your fresh water tank and allow the tank to drain completely.

Fresh Water Tank Low Point Drain
Fresh Water Tank Low Point Drain

Step 7)  Open all your faucets in the trailer to aid in draining the water lines in step 2.  This would include any outdoor shower that you may have.  If you don’t open your faucets there will be a certain amount of vacuum holding water in the lines.

Step 8)  Next, turn your water pump on for a few seconds in order to push any water out of the pump into the water lines.

Step 9)  Once you feel all the water has drained out of the water lines you can close all of your faucets, water heater relief valve, and the low point drains.

Step 10)  Now turn the valves on your hot water heater so that it is in the winter mode (also known as by-passing the water heater).  You are going to do this so that RV antifreeze does not enter the hot water heater.  In the picture below I could only capture two of the valves in the picture.  The bottom right of the picture shows the cold water line into the heater in the closed (winter) position.  The Valve in the middle of the picture is open to allow water to bypass the heater.  Likewise there is a valve on the top on the hot water line coming out of the heater that is also closed.   If you are blowing out your lines with compressed air you will need to do this so that air is pushed through the water lines.

Water Heater ByPass
Water Heater By-Pass

Keep  in mind every water heater is plumbed differently.  In almost all of our travel trailers, due to different floor plans,  the water heater has been located in a different place.  Also,  the by-pass handles have not always been set up exactly the same.  The concept of bypassing is always the same; prevent water from coming into the hot water tank. If you are unsure of how to by-pass your water heater consult your owner’s manual.  Here is an illustration of by-passing the water heater; the oblong black circles represent the water valves.  The illustration may better illustrate the process than the picture above.

water heater by-pass

Step 11)   Connect your blow plug and set your compressor so that it does not exceed 40 PSI.  If you are using RV antifreeze; this is the step where you will insert the draw tube located by your water pump into the jug of RV antifreeze, and turn on your water pump.  If you are blowing your lines out with compressed air, you may want to turn the water pump on for just a few seconds (check your owner’s manual).   Also, if you use a compressor you will probably want to use an air filter on your line.

Blow Out Plug Connected To Water Line
Blow Out Plug Connected To Water Line
Blow Out Plug
Blow Out Plug

Step 12)  Now go to the faucet furthest away from the water pump;  open the hot water faucet until antifreeze comes out; then close it and repeat with the cold water faucet.   Note: If using antifreeze you may need to switch over to a new gallon at some point during this process.  If you are using compressed air you will do the same thing and just close the faucet when only air comes out of the line.  Now progress through the trailer and follow the same process for any water fixture:

  • Toilet
  • Bathroom Shower
  • Bathroom Sink
  • Kitchen Sink
  • Outside Shower
  • Black Tank Rinse Port (if you have one)

Step 13)  If you are using compressed air and have finished the above steps, you can turn off your compressor and open the low point drains again.  Now turn the compressor back on to push any remaining water out of the lines.  This step is not necessary if you have winterized with RV Antifreeze as it will result in antifreeze draining out of the water lines.

Step 14)  Next, regardless of which process you are using to winterize your travel trailer (compressed air or antifreeze); everyone must pour antifreeze in every sink and shower drain.  This will protect the P-Traps from cracking, so don’t be stingy with the antifreeze.  Finally put antifreeze in the toilet bowl.

RV Antifreeze
RV Antifreeze

Step 15)  Decide at this point if you will place any D-Con, or other pest repellant in the travel trailer.  When we were living in Wisconsin our trailer was stored outside so we placed de-con in two areas in the trailer.   Make sure that if you have pets, the poison is located in areas that they cannot access (like the under bed storage area).

Step 16)  Remove everything from your trailer; this includes all food, cleaners, paper products, etc.

Step 17)  Fully inflate, or slightly over inflated (say 5 PSI over inflated) the travel trailer tires; because you will lose air over the winter months.

Step 18)  Level your trailer.

Step 19)  Finally, remove your battery and place it on a trickle charger or at the very least disconnect it.  As a result of not putting the battery on a trickle charger you are taking a risk;  as it will probably be dead when you return.

In Conclusion

These steps should provide a basis for you to create your own checklist.  As I mentioned, knowing how to winterize a travel trailer will save you a lot of time and money.  Some RV owners have no desire to learn how to winterize a travel trailer, opting instead to have a dealership perform this task.  Ordinarily this is because they want the warranty that the dealership provides against pipes bursting.   As with everything, if you are uncomfortable winterizing your travel trailer, seek out an RV service to perform the procedure.  Every Travel Trailer must be winterized; unless you keep it in a heated storage facility.

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