The ornamental design for a pumpenclosure, as shown and described.
FIG. 1 is a front view;
FIG. 2 is a top view;
FIG. 3 is a bottom view;
FIG. 4 is a side view; and,
FIG. 5 is a view of the back of the enclosure.
The broken line showing of elements in FIGS. 1 through 4 are included for the purpose of illustrating portions of the pump enclosure that form no part of the claimed design.