For a set of merging galaxies in the local Universe, we use archival Chandra X-ray data along with published 2.6 mm CO and 21 cm HI fluxes to determine the hot, cold, and warm interstellar gas masses, respectively. We determine how the relative amount of the different gas phases vary with merger stage, star formation rate, star formation efficiency, and stellar mass. We use these results to test models of stellar feedback during merger-triggered starbursts.