The ornamental design for a heatexchangerfinassembly, as shown and described.
FIG. 1 is a partial, top plan view of a heat exchanger element illustrating my new heat exchanger fin assembly design;
FIG. 2 is a bottom plan view thereof;
FIG. 3 is a front end elevation view thereof; and,
FIG. 4 is a right side elevation view thereof.
The rear end elevation view of my new design is a mirror image of the front end elevation view shown in FIG. 3.
The left side elevation view of my new design is a mirror image of the right side elevation view shown in FIG. 4.
The heat exchanger fin assembly is shown broken away to indicate that any portion of the article beyond what is shown forms no part of the claimed design.