Antifreeze Up: Completely empty the water system using the rig's built-in, low-point drains, and unscrew the drain plug from the water heater. You can blow the remaining water from the system with an air chuck adapter that allows you to connect an air hose to the rig's water fill fitting. Another option is to buy a couple of gallons of RV-style, freshwater-system, potable antifreeze. Pump it through the plumbing using the rig's built-in winterizing hose and run each faucet until the pink antifreeze appears. If the RV has no winterizing fitting, dump the antifreeze in the freshwater tank and use the water pump.