LG Microwave Repair

LG microwaves fall into two groups. Over-the-range models, including those with LG's ExtendaVent and convection features, work as both microwave and range hood, with a vent fan, lighting and grease filters. Countertop models, including LG NeoChef units, often use inverter technology, which replaces the traditional heavy transformer with an inverter board that controls power continuously rather than cycling on and off.

The failure that matters most is a microwave that runs but does not heat. On standard models, the cause may be a failed magnetron, diode, capacitor or high-voltage fuse. On inverter models, the inverter board itself can fail, which is a different and more expensive part. Door switch failures can blow the main fuse and leave the unit dead. Touch pads on over-the-range units may stop working after years of steam, and vent fans can grind or stop. A loud hum or buzz during heating often signals a failing magnetron or high-voltage component.

Owners can check the outlet and breaker, clean the grease filters under an over-the-range unit, and make sure the turntable is seated on its coupler. Do not open the cabinet. Microwaves contain components that store dangerous voltage after unplugging, and inverter boards also carry high voltage. If you see arcing inside, stop using the unit and look for a damaged cover in the cavity wall.

We discharge the high-voltage system, test the magnetron, diode, capacitor and transformer, or the inverter board on inverter models, and test the door switches and main fuse. On over-the-range units we inspect the vent motor and check that the unit is securely mounted, since sagging can cause door misalignment.

Over-the-range LG microwaves are usually worth repairing for switches, fuses, fans and many high-voltage parts, because replacement includes removal and installation. A failed inverter board or magnetron in a countertop model may not be worth it, and we will say so.