For future reference, it was just the fuse on the inverter board. It's a 2A SMT, possibly 0805. Our Agilent guru, CV, seems to recall that it should have been 3A or 4A, the latter of which I happened to have on hand.
We have glitchy power outages from fallen trees around here and when the interrupter cuts power to the neighborhood, it's BANG, BANG, BANG. Not surprised there may be some power up surges.