FIG. 1 is a top front and left side perspective view of electronic heater showing my new design;
FIG. 2 is a top rear and left side perspective view of electronic heater showing my new design;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a left side elevational view thereof;
FIG. 6 is a right side elevational view thereof;
FIG. 7 is a top plan view thereof; and,
FIG. 8 is a bottom plan view thereof.
Those portions of the illustrated design indicated by broken lines form no part of the claimed design.