FIG. 1 is a perspective view of our ornamental design for a heating and cooling unit;
FIG. 2 is a first side view of the heating and cooling unit shown in FIG. 1.
FIG. 3 is a second side view of the heating and cooling unit shown in FIG. 1.
FIG. 4 is a third side view of the heating and cooling unit shown in FIG. 1.
FIG. 5 is a fourth side view of the heating and cooling unit shown in FIG. 1.
FIG. 6 is a bottom side view of the heating and cooling unit shown in FIG. 1; and,
FIG. 7 is a top side view of the heating and cooling unit shown in FIG. 1.
The present application is directed to the design illustrated in the drawings. The elements shown in broken lines are included for the purpose of illustrating environment and form no part of the claimed design. Broken lines having unequal line segments illustrate the boundary of the claimed design.