Using the below system I have attached as a blueprint, I have noticed that if I replace the standard furnace with a blast furnace, the blast furnace correctly accepts the fuel and the items, but automation does not initialize smelting when the furnace receives its materials.  The system works normally with a normal furnace, however, so this is a missing implementation in blast furnaces.  It might also be present in smokers but I have not checked.

I do not believe this is intentional as the furnace still accepts the fuel and item and even puts them into the correct slots.  With both slots filled, it simply does not begin smelting.