Heater

FIG. 1 is a front, right, top perspective view of a heater, showing my new design;

FIG. 2 is a rear, left, bottom perspective view thereof;

FIG. 3 is a front elevational view of the enlarged scale thereof;

FIG. 4 is a rear elevational view of the enlarged scale thereof;

FIG. 5 is a left side view of the enlarged scale thereof;

FIG. 6 is a right side view of the enlarged scale thereof;

FIG. 7 is a top plan view of the enlarged scale thereof; and,

FIG. 8 is a bottom plan view of the enlarged scale thereof.

The dashed broken lines in the figures are for the purposes of illustrating portions of the heater and form no part of the claimed design.