We have Aqua Hot on our coach. It's not a good idea to winterize by blowing out the air, as in traditional methods. My water pump is in the wall of a storage bay. Here's what I do, and it takes about 15-20 minutes.
Go to any hardware, or big box store and buy one of those braided silver hoses that are used to hook up water to a washing machine. They come in various sizes. You'll need one that will reach from the water pump to wherever you can sit the bottle of pink stuff so it won't tip over while you are doing this task.
Screw the hose on to the water inlet of the water pump (its an exact fit). Stick the other end in an open bottle of the pink stuff. In my system, I generally need 4 bottles of the stuff because I have a washer/dryer combo. Have them open and ready to go. Now, have someone (the DW perhaps) go in to the coach and first turn on the water pump, and then each water facucet in the motorhome (one at a time, not all at once), including all sinks, showers, and lastly the toilet. The water pump will suck the pink stuff out of the bottle very quickly, so have a communication system where you can tell your partner to stop when you need to change bottles. We use hand held walkie talkies. Your partner should let you know as soon as the pink stuff is flowing in first the hot water and then turn it to the cold water. Do that for each sink and water outlet inside the coach, including the shower. Then open the toilet and let it run until the pink is coming out. I usually have some left over, and take that in to the coach and dump it down each drain, including the shower. We have done it so many times, we can complete it smoothly in about 15 to 20 minutes.
Its especially important to get the pink stuff running through the hot water because that winterizes the water system of the Aqua Hot. If those coils freeze they will rupture and you are looking at an expensive repair bill. Blowing air through doesn't get the water out of the bottom of the coils.
I follow the Splendide winterizing for the washer/dryer combo.
The only other way to keep the Aqua Hot from freezing is to stay below Interstate 10 from November to April!