Winterizing Your RV with Antifreeze

How to Winterize Your RV Using Antifreeze

Annie A. - Storageville Content Creator

Autumn’s changing leaves, brisk nights, and dwindling day light hours is a sure reminder that soon RVs everywhere will be hibernating for winter. For RV owners this means that it is time to winterize your recreational vehicle’s plumbing system.

There are two methods that can be used when it comes to RV plumbing, the compressed air method, and the antifreeze method. However, most, if not all RV manufacturers (Jayco, Keystone, Winnebego, Airstream etc.) owner’s manuals urge the importance of using RV Antifreeze for winter protection and strongly dissuade from using any pressurized air in the plumbing system as it can cause severe damage to your plumbing.

In this blog post, we will guide you step-by-step on how safeguard your recreational vehicle’s plumbing system using RV Antifreeze, yes, it is different from the stuff you put in your car.

Before diving in, please consult your RV Owner Manual for manufacturer-specific winterization protocols .

First and foremost, dump the RV waste tank.

Please ensure to follow all local and state laws in regards to dumping your RV’s waste tanks. For Example, you might be wondering if it is legal to empty your RV black water tank into your house septic tank. The short answer is yes, but it comes with a hefty slew of if’s and’s, and but’s. Should you? Not without doing research first.

If you are having trouble finding the appropriate dump site facilities we have compiled a list of RV Dump Stations in El Dorado County

Plumbing System:

The day before you begin the process, turn off any propane and or electricity to the hot water heater to avoid any potential burns. Hot water tanks are really well insulated and can keep water hot for up to 2 days. If your water heater is tankless or on-demand you do not need to do this.

The day of winterization you will want to level your RV, as well as open any slide-outs or pop-outs to allow full access to all areas of your RV.

Empty The Water Heater:

1. Disconnect the water supply by turning off the city water connection or by closing the valve that supplies water to your water heater. If you use a tankless system, you will want to turn off the on-demand pump.
2. Open any set of hot and cold water faucets inside the RV to release pressure in the tank.
3. Open the pressure release valve on the hot water tank.
4. Remove the water heater drain plug.
5. Let drain. – There may be a small amount of water left in the bottom of your tank, this is okay as it is such a minute amount that if freezing temperatures occur the remaining water will not expand enough to cause damage.
6. Close the pressure release valve, and replace the drain plug.
7. Turn the hot and cold water faucets from step 2 off.

Bypass The Hot Water Heater:

This is done to prevent antifreeze from entering the hot water heater. Your RV Owner’s Manual should have a depiction of what this looks like under the section labeled plumbing.

Please Note: The image below is an example image from a 2018 Jayco Owner’s Manual: Your system may look different and you should consult your RV’s Owner’s Manual specifically.

Low Point Drains:

Your low point drains are typically found on the underside of your RV. There should be 3 drains in total; cold water lines, hot water lines, and fresh water tank.
Close all low-point drains once devoid of water.

Close Fresh Water Tank Shut-Off Valve:

The valve should be located near the water pump.

Now you are ready for RV Antifreeze

Pro Tip: RVs typically use 2-3 gallons of antifreeze, you can dump your RV antifreeze into a clean 5-gallon bucket to prevent the mess of moving the siphon hose between individual gallon bottles of antifreeze. To help the gravity feed of the siphon place the bucket on a flat surface about 2 feet above ground level.

Open the siphon valve at the water pump. Insert the clear siphon tubing into a jug (or the 5-gallon bucket mentioned in our pro tip) of antifreeze. If you cannot find clear tubing near the water pump look for a hose that is roughly 2-3 feet long with a cap on the end of it.
Be sure that the water tank shut-off valve is OFF. You do not want antifreeze to enter your fresh water tank.
Turn ON the water pump. This will allow the antifreeze to be pulled into the water lines.
Open the hot water faucets inside your RV: Kitchen, bathroom sink, bathroom shower, outside shower. Do this until you can see antifreeze flowing continuously. -NOTE: IF your RV has a dishwasher or washing machine (for clothes) you may want to check each appliance’s winterization instructions as you can most likely winterize them at the same time as the rest of your plumbing. Just be sure to wipe the insides down to prevent residue and staining.
Close the hot water faucets and outside shower faucets. Then repeat the process, this time opening the cold water faucets inside of your RV, including the outdoor shower.
Flush the toilet until you see antifreeze in the bowl- this could take several flushes.

Once you are done adding RV antifreeze:

Turn the water pump off
Turn the siphon valve off, and remove the hose from the container of antifreeze.
Leave the water tank shut-off valve in the closed position to prevent antifreeze from entering the fresh water tank.
Treat all P traps and drains with RV antifreeze. Each drain and/or P trap takes approximately 1 cup of antifreeze to be sufficiently protected.
Immediately clean any spills or droplets of antifreeze to prevent staining or discoloration. If you are worried that your faucets will drip you can place paper towels under each faucet to prevent staining from occurring. The same can be done a shower head with a wand attachment, we recommend leaving the shower head wand in the shower pan, instead of hanging on the wall.

Congratulations! You have now successfully winterized your RV’s Plumbing System!

Up Next: Preparing Your RV’s Interior and Exterior for Safe Winter Storage.

Items You May Need While Winterizing Your RV Plumbing System

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