The ornamental design for a coolingunit, as shown and described.
FIG. 1 is a top perspective view of a cooling unit showing our new design;
FIG. 2 is a top view thereof;
FIG. 3 is a bottom view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a rear view thereof;
FIG. 7 is a front view thereof;
FIG. 8 is a top perspective view of a cooling unit showing another embodiment of our new design;
FIG. 9 is a top view thereof;
FIG. 10 is a bottom view thereof;
FIG. 11 is a left side view thereof;
FIG. 12 is a right side view thereof;
FIG. 13 is a rear view thereof; and,
FIG. 14 is a front view thereof.
The broken line showing of a remainder of the cooling unit in FIGS. 1-7, including the unshaded areas therein, is for illustrative purposes and forms no part of the claimed design.