How to Winterize an RV, Step by Step

Winterizing is not complicated, but it is unforgiving: one line you forget is the one that splits. This is the complete process in the order that works, including the components people miss most. Budget 1 to 2 hours your first time and have 2 to 3 gallons of pink RV antifreeze, a water heater bypass (most rigs have one built in), a pump siphon kit or hand pump, and basic sockets for the water heater plug.

Before you start

Park level, turn off the water heater, and let it cool completely. Draining a hot tank is a burn risk and hard on the tank. If your rig has been plugged in, flip the water heater breaker and gas valve off and give it a few hours.

The process

1. Drain the fresh water tank. Open its drain valve and let it empty completely. The tank itself stays empty all winter; it never gets antifreeze.

2. Drain the water heater. With the heater cool and the pressure relief valve flipped open, pull the drain plug or anode rod. On rigs with an anode, this is the moment to inspect it; a mostly eaten anode goes on the spring shopping list.

3. Open the low-point drains. Usually a red and a blue line under the rig or in a compartment. Open both, then open every faucet inside to break the vacuum so lines actually empty. Let everything run dry, then close it all.

4. Bypass the water heater. Behind the water heater’s interior access panel, flip the bypass valve (or valves) so antifreeze routes around the tank instead of filling it. No factory bypass? A kit costs little and installs in minutes, or skip the bypass and accept burning 6+ extra gallons.

5. Feed antifreeze to the pump. Connect the pump’s siphon kit hose into the antifreeze jug. No siphon kit? Use a hand pump at the city water inlet instead and push antifreeze backward through the system.

6. Run every fixture until it runs pink. Turn the pump on, then work through the rig one fixture at a time, hot and cold sides separately: kitchen faucet, bathroom sink, shower, toilet (hold the flush until pink), and the two everyone forgets, the outside shower and any exterior spray port. Each one runs until solid pink flows.

7. Hit the extras. Ice maker lines, residential fridge water, washer hookups, dishwasher, and macerator toilets each hold water. Check your manuals; ice makers in particular are a classic spring casualty.

8. Protect the drains. Pour a cup of antifreeze into every P-trap: sinks, shower, and the toilet bowl to keep its seal wet.

9. Finish the system. Pump off, city water inlet pressed to relieve pressure (a little pink should spit out), and a final walkthrough confirming every fixture ran pink.

10. The non-plumbing items. Batteries stored or tended, propane off, and a note taped by the door that the rig is winterized so nobody runs the pump dry in January.

The spots that cause spring surprises

The outside shower is the number one miss, followed by ice maker lines, washer hookups, toilet sprayers, and the low-point drains themselves (left open all winter, they invite pests; closed too early, they trap water). If your rig has a water filter housing, pull the cartridge and reinstall the housing empty.

When to hand it off

If any step above reads like a foreign language, or your rig has a residential fridge, washer, or hydronic heating, the math favors a pro. A Whaleshine technician winterizes at your driveway or storage lot from $189, every fixture photo-documented in your service record, and if it’s not right, we make it right. Book winterization two to three weeks before your area’s first freeze; our timing guide by region is here.