Originally Posted by robert.juric
I don't have a problem cutting a hole in the ceiling drywall, but I'm concerned that I can't remove the blocking between the i-beams.
Forget the Ibeam route altogether.
I'm going to assume that the furnace and AC is in the basement...
look for a spot down there that is 1) on the same side of the basement as the equipment and 2) will give you a clear shot up to the second floor.
THAT is where you need to cut a hole in the floor for your duct.
Once in place you can then extend it horizontally to the equipment.