To winterize an RV, you empty every part of the water system (fresh, gray and black tanks, the water heater and the low-point drains), bypass the water heater, and then either blow the lines out with compressed air or pump RV antifreeze through every faucet, shower and toilet until it runs pink. Finish by protecting the batteries, engine and generator for storage. Many rigs need about two gallons of RV antifreeze, larger plumbing systems need more, and valve layouts vary, so keep your owner’s manual open while you work.
What do you need to winterize an RV?
| Supply | What it is for |
|---|---|
| RV and marine antifreeze (never automotive antifreeze) | Protects water lines, traps and fixtures from freezing |
| Water pump winterizing kit or bypass tube | Lets the onboard pump draw antifreeze straight from the jug |
| Water heater bypass valves (factory or aftermarket) | Keeps antifreeze out of the water heater tank |
| Tools to remove the water heater drain plug or anode | Drains the water heater completely |
| Air compressor with a blowout plug and pressure regulator (optional) | Clears water from lines if you use the compressed air method |
| Battery maintainer or solar charger | Keeps batteries charged during storage |
| Fuel stabilizer | Protects the engine and generator fuel systems |
How do you winterize an RV step by step?
This sequence follows the wet (antifreeze) method described by Keystone RV’s winterizing guide and Winnebago’s RV winterizing guide. Your manual wins wherever it differs.
- Turn off the water heater and let it cool. Winnebago suggests switching it off the night before so the water will not scald you.
- Dump and flush the tanks. Empty and rinse the black tank, then empty the gray and fresh water tanks.
- Relieve pressure and drain the lines. Disconnect city water, turn off the pump, open the faucets and open the low-point drains, which are usually under the RV near the water heater.
- Drain the water heater. Open the pressure relief valve, remove the drain plug or anode, and let it empty. Inspect the anode rod while you are there.
- Remove water filters. Take out any filter cartridges, including a whole-house filter, before antifreeze goes in.
- Bypass the water heater. Set the bypass valve or valves to the winterize position. Layouts vary, so check your manual.
- Close the drains and pump antifreeze through. Reinstall the plugs, close the low-point drains, connect the pump’s winterizing tube to the jug and run the pump. At each faucet, run the hot side until pink antifreeze appears, then the cold side. Do the shower, outdoor shower and toilet too.
- Protect the traps. Pour a little antifreeze down each drain to protect the P-traps.
- Handle the extras. Follow your manual for ice makers and washers. Winnebago describes disconnecting and draining the ice maker supply line.
- Shut the pump off and cap the kit. Turn the water pump off and close up the winterizing connection.
Should you use antifreeze or compressed air?
| Method | How it works | Pros | Cons |
|---|---|---|---|
| Antifreeze (wet) | Pump RV antifreeze through the lines after draining | Protects traps and low spots where water hides | Uses a few gallons; needs flushing in spring |
| Compressed air (dry) | Blow water out through the city water inlet with an air compressor | No antifreeze taste in lines; quick to reverse | Can leave water in low spots; too much pressure can damage fittings |
| Both | Blow out the lines, then add antifreeze to traps and the toilet | Belt-and-suspenders protection | Takes the most time |
If you use compressed air, Keystone describes connecting the compressor with a blowout plug at the city water inlet and opening each faucet until no water comes out. Use a regulator and stay within the pressure your owner’s manual allows.
Which antifreeze should you use in an RV?
Use antifreeze labeled for RV and marine potable water systems. Keystone is explicit that it should be RV and marine grade, not automotive antifreeze. Winnebago describes pink RV antifreeze as safe for fresh water lines but not for drinking, which is why you flush it out before using the water system again.
How do you protect the engine, batteries and generator?
- Batteries: keep them charged with a solar or trickle charger, or plug into shore power from time to time, as Winnebago recommends.
- Engine: if the RV will sit, add fuel stabilizer. Winnebago suggests starting and driving the RV monthly to keep chassis batteries charged.
- Generator: Winnebago suggests running it about 30 minutes a month so fuel does not go stale.
- Propane, seals and pests: close the propane supply as your manual directs, check roof and window sealant, and remove food so rodents have less reason to move in.
Where you store the RV changes the risk. Our guides to RV storage costs and RV storage hacks cover the options.
How is winterizing a motorhome different from a camper van or trailer?
| RV type | Extra steps to plan for |
|---|---|
| Class A or Class C motorhome | Engine, chassis batteries and often a generator, plus more plumbing runs, washers or ice makers |
| Class B camper van | Compact plumbing and sometimes combination water and air heaters with their own drain procedures; follow the heater maker’s steps |
| Travel trailer or fifth wheel | No engine, but outdoor kitchens and showers are easy to miss; protect the batteries |
What are the most common RV winterizing mistakes?
- Forgetting to bypass the water heater, which can fill the tank with antifreeze.
- Leaving a water filter in place.
- Skipping the outdoor shower, ice maker or washer.
- Not running both the hot and cold side of each faucet until antifreeze appears.
- Using automotive antifreeze.
- Letting batteries go flat over the winter.
What if your RV is in a rental program over the winter?
Winter is slower in many markets, and some RVs stay in service where the weather allows. If your RV is in a rental management program, ask your Fleet Manager whether it will be winterized or kept available in your market and how the work is scheduled. In the RV Management USA program, preventative maintenance is billed to the owner and can be deducted from profits, and you can use the RV on unbooked dates, with notice.
Planning for the slow season is part of the income picture. Our guide to preparing your RV for seasonal demand and storage and our breakdown of how much you can make renting out your RV show how seasons affect earnings.
How do you de-winterize an RV in spring?
Reverse the process: put the water heater bypass back to normal, reinstall filters, connect water and run every faucet until it runs clear of antifreeze, then follow your owner’s manual for sanitizing the fresh water system. Check the batteries, tires, roof seals and propane system before the first trip. Our routine maintenance checklist for RV owners covers the rest.
RV winterizing FAQ
How much antifreeze does it take to winterize an RV?
Winnebago suggests buying about two gallons, though your manual may call for more on larger rigs with more fixtures.
When should you winterize your RV?
Before the first night your area is expected to drop below freezing, 32°F. If you are unsure, do it early.
Can you use car antifreeze in an RV?
No. Use RV and marine antifreeze made for potable water systems, never automotive antifreeze.
Do you need to winterize an RV stored in a heated building?
If the space reliably stays above freezing, the risk is lower, but a power outage or heater failure can still freeze lines. Many owners winterize anyway for peace of mind.
Can you winterize an RV without antifreeze?
Yes, with the compressed air method, but water can remain in low spots and traps. Many owners still add antifreeze to the traps and toilet.
Put your RV to work instead of in storage
If your RV spends months winterized and parked, rental income in the seasons it is not in use can help cover storage, insurance and upkeep. Talk with a Fleet Manager and the RV Management USA team to see whether your RV qualifies and what a realistic month could look like.
