The ornamental design for panel for air-conditioner, as shown and described.
FIG. 1 is a perspective view of a panel for air-conditioner showing my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a plan view thereof;
FIG. 5 is a bottom view thereof;
FIG. 6 is a left side view thereof;
FIG. 7 is a right side view thereof; and,
FIG. 8 is a cross-sectional view thereof along the line 8-8 in FIG. 2.
The broken line showing of the panel for air-conditioner is for the purpose of illustrating portions of the article and forms no part of the claimed design.