I have encountered several problems concerning an acceptable solution for draining a high-efficiency furnace & humidifier condensate. If I connect a condensate line directly to the p-trap of a washtub/sink, the sink may back-up and water could enter the furnace. If I drain the condensate into the sump pump pit, the pump will not eject any water since the outside lines are frozen. If the condensation is released into the basement floor drain, pvc pipes would have to run across the basement laundry room floor. If I drain into the wash tub/sink all the way from the furnace, a condensate pump and check valve would be required. What do you consider to be the most appropriate solution, considering the corrosive properties of furnace condensate.