55-65 is ideal, but they will be fine at house temps for at least a week. They will keep longer at the lower temperatures. I keep mine in my utility room which runs a few degrees cooler than the rest of the house and set them in the incubator about twice a week.
Webfoot
I'm going to be the voice of dissent here:D
I wash all my duck eggs before I set them in the incubator. Ducks are messy and it's just a fact of life that their eggs will be dirty. I've done my own research comparing the hatch rate of washed eggs vs. unwashed and I've found no difference...