How to Clean an AC Unit Inside Your House Without Damage (5 Parts You Can Touch, 3 You Shouldn’t)
Most guides on cleaning an indoor AC unit hand you five steps and stop. What they don't tell you is where those steps quietly cross from "helpful maintenance" into "that repair could have been avoided."
Here's the short version. You can safely clean the filter, the return grille, the outside of the cabinet, the visible drain opening, and your supply registers. The evaporator coil, the blower wheel, and the inside of the drain pan belong to a technician, because each one has a mechanical reason it fails when handled wrong.