I bought a hand pump that screwed on the city water inlet and pump antifreeze until it bypasses the check valve then I know I am safe ... also if you have a blackwater tank wash inlet make sure to pump antifreeze into it until it opens check valve
If you are just blowing out, don't worry as that is where you probably hooked up the air; there is no water left. If you are using AF, push the button with the system AF filled and under pressure (and stand to the side). Hold until some AF spurts out of the fitting.
Linear Mode
