I claim the ornamental design for a front panel for portable air conditioner, as shown and described.
FIG. 1 is a perspective view of a front panel for portable air conditioner showing my new design, with the rear elevation view hidden and therefore not part of my claimed design and the broken-line disclosure representing portions of the article in which the claimed design is embodied, but which form no part of the claimed design;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a side elevation view thereof, with the other side being a mirror image;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom plan view thereof; and,
FIG. 6 is perspective view of the front panel for portable air conditioner in the open vent condition.