How to winterize. 3 mentods (NOTE: Does not matter if Motor home or Trailer)
Wet metod:
Open all valves, INClUDING LOW POINT, drain systgem, Bypass water heater and drain it. Close all valves and pump RV Antifreeze into all lines.... Downside,, Getting that pink crap out come spring
Dry Method: Again bypass and drain water heater (Oh, note, on Atwood disconnect red wire from ECO) Open all valves and drain lines. Screw a BLOW OUT PLUG into the city inlet and blow 50 PSI, till no more water comes out.. Wait a few minutes, blow again, Do this like 5-10 times. Close all but low point valves
NOTES: after the FIRST blow run the on-board pump (Tank empty) for a minute to blow it out, also drain the inlet strainer on the pump. You need do this only after the first blow.
DO NOT forget to drain the main supply tank first.
Both methods.. Dump holding tanks, and then add RV antifreeze to toilets and drains,, enough that at least a pint goes into the tanks.
Best way to winterize:
Strap a snow blower to the front of your vehicle (Motor home or tow vehicle) Hook up and drive SOUTH.. When you stop for fuel and someone pushes their had back, looks strangly at the snow blower and asks "What the )(@#$ER is that thing?" you are winterized. (note this is a bit of a joke I'v seen freezing tremps that far south).