Nick, you are so lost.
Do you mean duct tape the coil? or the duct? or the grilles? You can
use dampers in the grilles to lower air flow, but better would be to
use a dehumidistat connected to a fan speed relay to lower the blower
speed when it is humid in the house. Using duct tape to fix the
problem is a bad idea. Nick, you should change your name to MacGyver!

Stretch