The ornamental design for a thermaldeflector for fireplaces, as shown and described.
FIG. 1 is a front elevational view of a thermal deflector for fireplaces
showing my new design; and
FIG. 2 is a side elevational view thereof.
The broken line representation of support structure in FIGS. 1 and 2 and
the fragementary broken line representation of a fireplace floor and wall
in FIG. 2 are for purposes of illustration only.