Ian D Alcoa , TN August 31, 2016 Appliance: LG Microwave Oven LMV1680ST Lg Microwave/Hood Combo Lmv1680st: Broken vent grille. How to replace Charcoal Filter (Mechanical), 1 Pack. Very easy fix - simply removed the two screws holding the old vent grille in place, slotted in the new vent grille, replaced screws and tightened. Done in two minutes. 1 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: Less than 15 minutes