If it was winterized properly and you never ran water through the lines or drained the anti-freeze you should be fine. In terms of your pump switch, this sounds like a momentary switch that turns on when pushed up, off when pushed down. Usually this type of switch in a camper is an indication that there is a second switch somewhere in the circuit (sometimes in the control panel and perhaps in a bathroom). IF your system is pressurized pusing the switch up woudl energize the pump circuit but the pump would not run as the pressure in the ilnes is high enough.
