When I winterize mine I open the low point drain valves then remove the Water Filter, housing and remove both hoses from the mouting housing. I then replace it with a short hose and male fittings. Next I close the hot (red) & cold (blue) valves at the back of the water heater and open the one on the vertical line between the hot and cold lines. Now i open all of the faucets and use a johnny chock on the toilet and using my air compressor with a tire inflator and an adapter that screws int the City water connection and blow all the water out of the lines ( make sure that you set the psi no greater than 100 psi. Now close all faucets and remove the johnny chock. Next I close the low point drain vales, remove the hose at the water pump(from the fresh water tank) and with a hose about 30 inches long with a connector that fits to the water tank ( a 90 deg. + a small hose clamp)and the other end with no connector put into the RV antifreeze bottle. Now turn on the pump to draw the fluid into all of the lines (you will need to open all of the faucets one at a time to make sure that only pink comes out as there will always be a little water left int the lines). you will need about two gals. to do it. In the spring just reverse the process. the first few times it may take about an hour to do it. Myself I can do it in about 20 min.
TV = 2003 1500HD 4x4 Chevy
Silverado Crew Cab 6.0L V8 W/3:73
2011 Rockwood HW296 16" Box