How to Flush Antifreeze out of a Trailer's Water System

••• Jupiterimages/Comstock/Getty Images

De-winterizing the trailer won't take much time, but it will require an appropriate location to dump the waste water. You can take additional steps to remove odor and taste from the lines to ensure fresh-tasting drinking water once the freshwater tank is filled for vacation.

Locate the freshwater inlet on outside of the trailer. Attach the potable water hose and fill the tank.

Locate the bypass water valve inside the trailer and set it to the open position. Leave the bypass to the water heater on and keep the drain plug off.

Locate the water pump switch and turn it on. Open the hot and cold water faucets in the trailer, including the shower. Flush the commode several times to flush away standing winterizing formula.

Take the trailer to a dump station and hook up one end of the waste hose to the waste pipe and secure the other end to the dump hole. Empty the black water tank first and the grey water tank second.

Take the water heater out of bypass and ensure the drain plug is in place. Fill the fresh water tank with water for drinking, cooking and showering.


  • Never allow antifreeze to enter the water heater. It will corrode the sacrificial anode and potentially damage the water heater.
  • Fill the water heater only when there is fresh, clean water in the system.


  • It is a good idea to disinfect the fresh water tank and lines with a bleach solution after draining the antifreeze.


About the Author

Olivia Emisar has been writing online articles since 2008. She graduated with her associate degree in liberal arts from the University of Hawai'i and pursued two additional years in the field of psychology. Her studies also include a year at the University of Reno with an emphasis in communication and women's studies.

Photo Credits

  • Jupiterimages/Comstock/Getty Images