If you own an RV and live in a place where winter temperatures routinely drop below freezing, you’ll want to take special precautions to prevent internal damage to the vehicle. Frozen water lines can cause extensive damage, but as they say, an ounce of prevention can go a long way to save you time, money, and headaches later on. 

It’s easy to winterize your RV using an air compressor. The process involves draining the tanks, flushing the system, and blowing it out with compressed air. You can also winterize the refrigerator and washing machine using an air compressor. Using air is safer than winterizing with antifreeze. 

Do You Need to Winterize Your RV?

Winterization or winterizing is the process of preparing your RV, home, vehicle, boat, or other machinery for the change in temperatures and harsher conditions that come with winter. 

Freezing temperatures can cause extensive damage to home plumbing systems, and your RV is no different. 

Winterizing also sometimes refers to preparing your home or RV for a vacant period. In most cases, winterizing your RV involves getting ready for both of these conditions. 

You’ll likely be dealing with freezing temperatures and you won’t be taking your RV out on the road, meaning you’ll need to get it ready to sit for extended periods. 

You need to winterize your RV if you plan to store it for the winter. If you’re in a residential RV, you’ll still need to winterize to prepare for the low temperatures, especially if you live in a place where temperatures consistently drop below freezing. 

So, in summary, you should winterize your RV if…

  • You plan to put your RV in storage for several months
  • Temperatures are at or below 20°F for extended periods
  • You can’t insulate your RV’s underbelly
  • You don’t have heated tanks in your RV
  • You’re limited on when you can run your furnace

Ways to Winterize an RV

There are two main ways to winterize an RV – using RV antifreeze or compressed air. Using antifreeze involves running the chemical through your plumbing lines and pouring it down all the drains. This method is expensive and may be harmful to the environment. 

Not to mention, you’ll have to thoroughly clean and rinse all of your lines and tanks before using any of the RV’s plumbing in spring. 

If you don’t want to fill your water lines with antifreeze or spend the money on the chemicals, you can winterize your RV easily using compressed air. 

Using compressed air may take a little longer than dumping antifreeze into your tanks, but it’s a better and more thorough method to winterize your RV. 

How to Winterize Your RV Using an Air Compressor

To winterize your RV using compressed air, you’ll need: 

First: Drain All Tanks 

The first step in winterizing your RV is to drain all the water from every tank. This is an important step that you should do anytime you put your RV into storage, even during the summer months. You don’t want water just sitting in your tanks and lines for an extended period. 

This means you should disconnect your fresh water hose and turn off the water pump. Drain all your tanks, empty and flush the sewage holding tanks, and open the low-point drain to completely drain the fresh water tank. 

Turn on the water pump for 20-30 seconds to get all the water out completely. Make sure you don’t let it run for longer than this or you could cause damage to the pump. It’s always a good idea to consult your owner’s manual for specifics.

Remove the water filter housing and filter, dumping any excess water. You can replace the housing once it’s emptied, but leave the filter out. You don’t want a soaked water filter sitting in the housing for months without use. 

You’ll also need to turn off the hot water heater so it can be drained, but you won’t want to attempt draining it until the tank has cooled. This could take several hours.

Second: Drain the Hot Water Heater 

Once you’ve given the water heater several hours to cool, confirm the pump is turned off and disconnect the water line. Turn a hot water faucet inside your RV to the “on” position to relieve pressure from the tank. 

Carefully open the pressure release valve and remove the drain plug. Be prepared for water to make a quick exit from the tank and stand clear of the stream. 

Once the water is drained, you can clean out the tank if you wish. There are specially designed sprayers just for rinsing out RV water tanks, making it easy to remove scale and sediment that may be building up inside. 

If your water heater has an anode rod, during the draining process is a good time to inspect and replace it if needed.

Third: Blow Out the Water Lines

After the water heater is drained, you can close the pressure relief valve and connect the blowout plug to the fresh water intake. You’ll also want to use an adjustable water pressure regulator to ensure you keep the pressure in the correct range. 

Usually, you don’t want to set the pressure over 40 PSI, but you should definitely check your owner’s manual for the specifications for your RV.

Before you start the process, open all the faucets inside the RV to let any last droplets of water drain out. When you don’t see any more water, close all the faucets and drains. 

Force compressed air through the lines, starting with the water heater and working your way to the inside lines. Once you’re done with the water heater, turn the water heater bypass switch. Check your owner’s manual if you’re not sure where it’s located. In some RVs this bypass lever is underneath the sink. 

Next, open each faucet one at a time and let the compressed air blow through it for about 30 seconds. 

Be sure to open each faucet individually. Don’t forget the shower head, outdoor shower, toilet, and kitchen sprayer nozzle if you have one. 

You may also need to force the water out of your refrigerator or ice maker if you have one. This will involve forcing air through the freezer’s water lines just like the other faucets. 

When you’re done, switch the settings on your RV to “tank fill” to blow out any water that’s left in the tank lines. 

Once no more water is coming out from any of the lines, you are ready to move on to the next step. 

Last: Finish with Antifreeze

The final step involves pouring antifreeze into the system. You should consult your owner’s manual for the specifics for your RV. In many cases, the manual will call for you to pour one pint of RV & Marine Antifreeze into each drain (sinks, tub, shower, toilet). 

It’s a good idea to wipe up any spills and splashes with a dry towel to prevent discoloration or damage to the sink’s surface. 

For toilets, you may need to flush antifreeze and leave some in the bowl. For other appliances like washing machines or washer/dryer combos, consult your owner’s manual.

What Size Air Compressor Do You Need to Winterize an RV? 

You don’t need much air pressure to winterize your RV. All you need is at least a one-gallon tank size and at least 0.5 CFM of airflow. The machine needs to deliver at least 30 to 40 PSI, but the exact recommended pressure setting will depend on your RV’s specifications. 

How Much Is It to Have Your RV Winterized? 

If you don’t want to do the winterizing process yourself, most dealers and service shops will winterize your RV for a fee. The cost will depend on your RV and its size, as well as the process they use for winterizing. Still, you shouldn’t have to pay more than $250 for winterization in most cases. 

If you already own an air compressor it makes more sense to do the job yourself if you have the time. That way, you only need to spend about $20 or less to purchase RV & Marine antifreeze to finish the job. 

How De-Winterize Your RV

When winter is over and you’re ready to get back on the road, it’s easy to get your RV back into service and de-winterize your plumbing. 

All you have to do is hook up your RV to a fresh water source or use your fresh water tank to cycle through the lines. Let the water run for several minutes to flush everything out. For your toilets, you just need to flush them several times to get the antifreeze out. 

If you put antifreeze into your fridge, freezer, or washing machine, it’s just a matter of cycling water through the lines to flush everything out. 

RV & Marine antifreeze isn’t toxic like automotive antifreeze, which is why it’s critical to use the correct type. Still, you don’t want to consume chemicals, so be sure to flush everything out thoroughly before using the water for consumption or showering. 

The Bottom Line

Winterizing your RV is a simple way you can protect the vehicle and keep it operating properly all year long. While it may seem like a hassle to do all the necessary steps, it’s well worth it when you consider the expense and headache that comes with dealing with burst pipes and other plumbing damage. 

Whether you use compressed air, antifreeze, or a combination of both, go with the method you’re most comfortable with after consulting your owner’s manual for guidance.