Mel,
The Hurricane system does not have a fresh water loop inside the Hurricane heater itself, so winterizing the system is just like winterizing a coach with a stand alone water heater on your year model coach.
First install a water heater bypass if you do not already have one. Next drain the water heater and be certain it is empty. Then pump the pink RV antifreeze through all water lines until it flows out the facet for both hot and cold. Don't forget the toilet, washing machine, and icemaker.
If you do not use a water heater bypass and drain the water heater, it will require and additional 6 to 8 gallons of RV antifreeze to winterize the coach. Or you can adopt my method of winterizing and GO SOUTH.
Gerald