FIG. 1 is a front perspective view of an air conditioner showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a left side elevational view thereof;

FIG. 7 is a right side elevational view thereof; and,

FIG. 8 is a generally vertical partial cross-sectional view thereof, taken along line 8—8 of FIG. 2.

The broken-line disclosure in the views is understood to represent portions of the article in which the claimed design is embodied, but which forms no part of the claimed design.