How Do I Winterize My Travel Trailer Using the Wet Method?
- 1). Drain all of the water tanks in your travel trailer, including the fresh water, gray water and galley water tanks. Empty the sewage tank.
- 2). Pour 4 to 6 gallons of RV-grade antifreeze into the fresh water storage tank.
- 3). Locate the water heater bypass valve and turn it to the bypass position.
- 4). Drain your water heater. Take out the water filter and throw it away.
- 5). Locate the water pump switch and turn it on. Open the cold water side of the faucet farthest from the water pump in the travel trailer, and wait for the antifreeze to come out of the faucet. Close that faucet and open the next one. Repeat for the hot water side of each faucet.
- 6). Flush the toilet. Pour 1 gallon of antifreeze into the toilet as antifreeze starts to fill the bowl to treat the black water tank. Pour antifreeze into each shower, tub and sink.
- 7). Pour 1 gallon of antifreeze into the gray tank's corresponding sink drain to winterize it.
Source...