Heat exchanger

FIG. 1 is a perspective view of a heat exchanger showing our new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a left-side elevation view thereof;

FIG. 5 is a right-side elevation view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof;

FIG. 8 is a perspective view thereof showing an exemplified use of the stopper;

FIG. 9 is an enlarged view of portion 9 in FIG. 8 ; and,

FIG. 10 is a perspective view of the heat exchanger shown in a state of use.

The broken lines shown in FIGS. 3 and 6 show portions of the heat exchanger that form no part of the claimed design. The broken lines in FIGS. 8 - 10 illustrate environmental structure of the heat exchanger and form no part of the claimed design. The dot-dot-dash lines in FIGS. 8 and 9 denote the boundary of the enlargement area and form no part of the claimed design.