As the temperatures drop, your RV needs a little extra protection from the cold. Water expands when it freezes, which can lead to leaking or burst pipes in your RVs water supply or drain lines. The main objective of winterizing is to replace the water in your lines with antifreeze, which will remain in liquid form even at very low temperatures.
RV repair facilities will professionally winterize your RV for you, but you can save money by doing it yourself. For this project, you’ll need:
- A few gallons of marine/RV antifreeze—exact amount varies by make and model
- A water-heater bypass kit if not already installed
- A cleaning wand (see #2 below)
- Water pump converter kit or tubing to connect to pump inlet valve
- Hand tools to remove drain plugs
Step 1: Remove or Bypass Water Filters
An RV owner’s first step is to remove or bypass any inline water filters since antifreeze can damage them. While working on the filters, check to see if they need replacement. If they do need replacing, you have all winter to find new filters at the best price.
Step 2: Drain the Tanks
First, drain the freshwater holding tank. Next, locate the drain plugs for the black and gray water tanks. Letting waste water sit in those for an extended period of time not only increases the risk of water freezing, but it lets potential harmful bacteria grow unimpeded. The tanks for black and gray water should only be drained at an approved dumping facility.
Drain the black water tank first. If your RV does not have its own tank-flushing system, use a cleaning wand to flush the black water tank. Products like Flush King also help flush out both waste water tanks. Once you’re finished, it helps to lubricate the termination valves with WD-40 for future use.
Step 3: Drain Water Heater and Lines
The water heater should not be hot or under pressure when it is drained, so turn the water heater off and let it cool. Turn on a faucet or two so that hot water is flowing out of it—this reduces the pressure within the water heater tank. Once it is cool and under less pressure, remove the drain plug to begin draining the unit. Opening the pressure relief valve and/or removing the anode rod helps the unit drain more quickly.
Open all faucets and locate and open the low-point drain plugs on the system. Flush the toilet to remove water in the tank. If you’ve got an outdoor shower, make sure to drain it as well.
Some people use the RV’s 12V water pump to force the water out completely. If you’re using the pump, be sure to turn it off as soon as soon as the water is out to keep the unit from getting damaged.
Once the water is drained, recap all drains and close all faucets.
Step 4: Bypass the Water Heater
You’re about to add antifreeze to your plumbing system, but filling your water heater would waste six to ten gallons of antifreeze. Many RVs come with a bypass installed, but if yours doesn’t have one, visit an RV repair facility to have on installed
Step 5: Add Antifreeze
You’re ready to pump the antifreeze in your system, which will protect your plumbing when the thermometer dips below freezing. There are two ways to do this:
- Install a water pump conversion kit
- Use the inlet side of the water pump
Water pump conversion kits will come with instructions on how to use them. If using the inlet side of the water pump, disconnect the line coming from the freshwater tank and attach tubing that connects to the inlet. Put the other end of the tubing into a container of non-toxic marine/RV antifreeze. Then turn on the pump, which will pressurize the plumbing system.
Starting with the closest faucet to the pump, slowly open the hot and cold faucets until antifreeze comes out. Once you see antifreeze, close the faucet. Do this to all faucets, working from closest faucets to pump to the farther faucets. As you pump antifreeze through the water lines, you may need to replace the antifreeze container. Don’t forget the outdoor shower.
Flush the toilet until antifreeze appears in the bowl. Introduce antifreeze into the drain lines and holding tank, so pour a cup of antifreeze in each drain and into the toilet bowl. Flush the toilet.
Turn the water pump off. Now open a faucet to release the pressure in the system. Go to the city water inlet valve. Remove the small screen and push on the valve with a screwdriver until antifreeze comes out. Replace the screen and close the inlet. Double check that the water heater’s heating element is switched off and that all faucets are closed.
Now your RV is ready for winter!