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How to Put Antifreeze in an RV Camper (Step by Step)

Putting antifreeze in your RV as part of the winterization process is sad for two reasons. First, your summer of fun is coming to an end. And second, because it can be expensive to pay someone else to do. It’s an easy process that RV owners can do without taking the vehicle to a shop.

Putting antifreeze in an RV is a big part of getting it ready for the colder winter months and not something to skip. Prepping an RV for winter is necessary to prevent any freezing in the plumbing system, an issue that can cause all kinds of issues down the road.

how to put antifreeze in rv

If it is time to put your RV camper away for the winter, be sure to read the rest of this so you can make sure you have all the supplies you need, step-by-step instructions, and also what mistakes you want to avoid.

By following these steps, you will be able to keep your RV camper running for years to come.

How to Put Antifreeze in an RV Camper: 6 Steps

Putting antifreeze in your RV is something that can very quickly be done at home without a professional mechanic.

And, without the mechanic price tag. Follow these steps to get the job done all on your own.

1. Gather the Supplies

Spending money on quality supplies is an investment that can last you quite some time. You’ll get plenty of use out of these as an RV owner.

You can also check RV owner groups online to see if anyone has these supplies that they’re willing to lend out or sell.

Here’s what you’ll need to put antifreeze in your RV:

  • Nontoxic RV/marine antifreeze
  • Water heater bypass
  • Tank cleaning wand to clean and flush the black water holding tank. If there is a built-in tank flushing system, you won’t need this.
  • Essential hand tools to remove and install drain plugs

If you don’t have any of these supplies, a Winter Readiness Kit will get you started. They come with a hand pump, blow-out plug, antifreeze concentrate, mini dehumidifier, and more.

What’s the best RV antifreeze?

The best antifreeze to use in your camper is going to be both non-toxic and biodegradable. Look for a burst protection rating of at least -50°F (-45°C).

Here are a couple of great choices on Amazon: Star Brite and Splash.

Once you have all the supplies lined up, you’re ready for action. Follow these steps to add the antifreeze to your RV.

2. Drain the Water System

You will need to be sure you have fully drained the water system. You do this by opening all the hot and cold faucets, including the toilet and outside shower.

You will also need to open the low-point drain lines; there will be one for the hot and cold water lines.

winterize rv with antifreeze

3. Empty the Lines (11 Steps)

You will need to blow out the lines to make sure they are clear. To blow out the water lines, you can follow the steps below.

  1. You should remove any inline water filters and bypass
  2. Drain the fresh water tank, including gray and black holding tanks.
  3. Remove the water from the water heater and water lines.
  4. Open the hot and cold faucets to drain water.
  5. Place the blowout plug to your water intake valve.
  6. Using an air compressor, connect the other end of the blowout plug.
  7. Set the air pressure to 30 psi up to 40 psi to avoid water line damage.
  8. Use the air compressor to blow strong air into the lines.
  9. Open up your water valves one at a time to blow out excess water from the lines.
  10. Remember to close the valve after blowing the water out from each line.
  11. Blow out all the water lines by repeating steps 10 and 11.

4. Bypass the Water Heater

You will need to use the water heater bypass to bypass the water heater. By bypassing the water heater, you will not need to put antifreeze in the water heater.

You should also bypass your filter or remove it before adding antifreeze to your system.

  • Find your heater. It is located on the outside of your van and is most likely located behind a large cover, with a screen on the upper right-hand side.
  • Open the screen. Behind it, you will find an anode that is usually removed when draining the tank for winterization. The anode gets loose with age, so replace it when it starts to look aged. You will need a 1- 1/16 socket for the anode rod.
  • Now go into your RV and find the heater from the inside. You may need to remove a cover to access it.
  • Cold water comes in at the bottom, and hot water comes out of the top of the heater. If your RV has a bypass valve, these two pipes will be connected directly to each other using a third pipe.
  • The lever of the valve should point in the direction that you want the water to flow. If it is turned 90 degrees towards the bypass line, it will flow into the bypass line and not enter the tank.
  • Both valves on the hot and cold water lines should be turned to prevent antifreeze from entering the hot water tank.
  • Remove the fuse of your heater to prevent it from going on while no water is in it.

5. Convert Water Pump

You will then install a water pump converter kit.

This will allow we allow you to bypass the freshwater tan and use the water pump to run the antifreeze through your water lines.

6. Add Antifreeze

You are ready to add the antifreeze now. You will do this in a number of steps to make sure you have covered everything that will need it.

  • Turn on the water pump
  • Open the faucet closest to you. You will turn on the hot and then cold until you see pink fluid. You will then need to do all faucets, including low point valves. Make sure you do not forget your showers (inside and out) and flush the toilet until you see antifreeze.
  • When you have done that, you are going to go and pour 1 cup of antifreeze down each drain.
  • When you are finished, close all the faucets.

What to Watch Out For

You want to avoid getting antifreeze into the freshwater tank. Trying to run it through the pump into your system will use a lot of antifreeze. Also, when the tank is empty, there is still some water in the bottom that will mix with the antifreeze, lessening its effect.

Make sure you completely drain the hot water tank. You need to pull the drain plug and also open the pressure pop-off valve. If you don’t completely drain it, the remaining water will freeze, potentially causing damage.

  • Don’t forget to winterize the sinks also. If you don’t pour antifreeze down the sinks, water can stay in the curved section and freeze, causing damage.
  • Don’t use too much antifreeze. Two gallons should be able to winterize the entire RV camper.
  • Don’t forget to do the grey and black water tanks. It is recommended that you fill each with fresh water, and you’re fine chemicals and let them sit for a week and then drain them. This will avoid any unpleasant smells when you open up next season.
  • Don’t forget to also take care of any appliances that have water in them like any ice machine. You will want to make sure anything that has water going through it is winterized.

More reading: Should you cover your RV in the winter? 6 Pros and Cons

Why it Matters?

When the weather turns colder, you run the risk of any water in the RV camper freezing. If this water freezes and expands, it can cause the pipes to burst, causing damage and leaving the RV camper potentially unusable.

Depending on how much water is left in the pipes, skipping the winterization process could be a costly mistake. It’s better to get the supplies to DIY the antifreeze process, rather than gambling with the possibility of frozen plumbing.

camper antifreeze

Congratulations on successfully adding antifreeze to your RV. Here’s how to flush antifreeze after the winter.

The Verdict

By adequately winterizing your RV every year, you can keep it in shape and damage-free from the long and cold winter months.

In the spring, you can be ready to enjoy the great outdoors without having to make repairs to your water lines and spending countless dollars before you can even enjoy your RV.

Have a tip to share? Or maybe a question? Let me know below!