Heat it to at least 900 °C. You have to cut the water supply for that, but it is possible with two cooling fins. Don't do it in the netherFirst, it's used to make blast glass which is needed for reactors, and according to the handbook it can also make steel faster, though I haven't figured out how to do that.
Edit: I actually wouldn't use it for that, not only because it doesn't give any bonus.[DOUBLEPOST=1409217885][/DOUBLEPOST]
Weird. It does work for me without problems.Nnnnope.
The slots on the fractionator are specific to each item. Precision export buses tend to fill things in the wrong order and on occasion i've found they bug out and refuse to export when I manually sort the order out in the GUI.
I needed a cunning arrangement of LP to manage it, but I finally got it working.