How to Winterize an RV

Before you start, gather your supplies: RV-specific non-toxic antifreeze (pink, propylene glycol-based; NOT automotive antifreeze), an air compressor with a blow-out plug adapter (available at RV stores for under $10), and any tools needed to access your water pump bypass kit. Use your owner's manual to locate the water heater bypass valve — you'll want to bypass the water heater so you're not pumping antifreeze into it. Turn off the water heater and let it cool completely before draining it. Never drain a hot water heater — the pressure release could cause burns. Empty the fresh water tank by opening the low-point drains, then run the pump briefly to move water through the lines.

The compressed air method is the most thorough way to remove water from the lines before adding antifreeze. Connect a blow-out plug to your city water inlet and attach the air compressor (use no more than 50 PSI — higher pressure can damage fittings and seals). Open each faucet one at a time — hot and cold — starting with those farthest from the water inlet and working your way forward. Hold each one open until the water flow stops. Repeat for the toilet, outside shower, and ice maker line if equipped. Blow out the washing machine connection if present. Finally, open the low-point drain valves while air is flowing to clear those lines. The air method removes most of the water but rarely all of it — residual moisture in p-traps and low spots makes a follow-up antifreeze treatment recommended for areas with severe freezing temperatures.

RV antifreeze (propylene glycol, non-toxic, pink) protects any remaining moisture in the system from freezing. With the water pump bypass kit installed (so the pump draws from an antifreeze bottle rather than the fresh water tank), run each faucet until you see the pink antifreeze appear — that confirms the line is protected. Do this for every hot and cold faucet, the toilet flush, the outside shower, and the ice maker line. Pour a small amount of antifreeze directly into each drain — sink drains, shower drain, toilet bowl — to protect the p-traps. Also pour some into the toilet bowl and flush it through. Add antifreeze to any exterior drains as well. Some owners also add a cup to the fresh water tank to protect the tank itself if any moisture remains.

Beyond the plumbing, proper storage preparation protects your investment through the off-season. Disconnect and store the house batteries (or use a battery maintainer to keep them at float charge — batteries that sit discharged through winter will sulfate and fail). Remove all food and consumables from the refrigerator, cupboards, and pantry — rodents and insects will find anything left behind. Prop the refrigerator door open slightly to prevent mold. Remove all medications and personal care items that can freeze. Check tire pressure and inflate to the maximum recommended pressure for storage. If storing for more than 2–3 months, consider placing the RV on tire cradles or flat boards to prevent flat-spotting. Apply a UV protectant to all rubber seals and tires. Cover the RV if storing outdoors — a quality cover protects the roof and seals from UV damage and reduces cleaning in the spring.