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HomeRepair HelpLG Microwave RepairLG Microwave producing a burning smell Repair
LG Microwave producing a burning smell
If your LG microwave smells like burning, stop using it until you identify the source. The most likely cause is a damaged or loose waveguide cover, which can arc or burn and should be replaced if it will not stay in place. Next, inspect the power supply board for burn marks or a shorted component. A failing high-voltage capacitor or capacitor can overheat while working with the high-voltage diode and transformer, creating a burning smell from the microwave. A damaged thermostat is another possible cause. Also check the interior cavity for food debris or dried spills, since leftover food can continue cooking and make the microwave smell burnt. Any repair that requires removing the outer cabinet involves lethal high voltage: the high-voltage capacitor can retain a lethal charge even after the microwave is unplugged and must be properly discharged before interior work. Repairs involving the power supply board or high-voltage capacitor may require a qualified technician if you are not familiar with capacitor discharge procedures. Enter your LG microwave model number to find the exact replacement waveguide cover, power supply board, capacitor, or thermostat for your specific appliance.
01 - LG Microwave Waveguide Cover
The waveguide cover might be damaged and arcing or burning. If this is the case or if the cover will not stay in place, replace it with a new one.
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02 - LG Microwave Power Supply Board
If you've confirmed the oven cavity has been cleaned of all food debris and the waveguide cover is in good condition, a defective power supply board could be one of the components producing a burning smell. You should inspect the board for any burn marks or a shorted component and replace if necessary.
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03 - LG Microwave High Voltage Capacitor
The high voltage capacitor works with the high voltage diode to convert the output of the transformer to DC voltage and to double the output voltage. A defective capacitor may overheat and produce a burning smell. Inspect the capacitor for visible damage or burn marks and replace if necessary.
Highly Likely
04 - LG Microwave Capacitor
The capacitor works with the high voltage diode to convert the output of the transformer to DC voltage and to double the output voltage. A defective capacitor may overheat and produce a burning smell. Inspect the capacitor for visible damage or burn marks and replace if necessary.
Highly Likely
05 - LG Microwave Thermostat
If you've confirmed the oven cavity has been cleaned of all food debris and the waveguide cover is in good condition, a defective thermostat could be one of the components producing a burning smell. You should inspect the component for any burn marks or damage and replace if necessary.
Highly Likely
06 - Interior Cavity not Clean
Food that is left on the interior of the microwave can continue to cook each time the microwave is used, resulting in a burning smell. Always cover food when cooking to avoid splatter and wipe up any spills after use.
Highly Likely
Frequently Asked Questions
Why does my LG microwave smell like burning?
Can a damaged waveguide cover cause a burning smell in my LG microwave?
What if my LG microwave still smells like burning after I clean it?
Is a burning smell from an LG microwave dangerous?
How do I find the correct LG microwave waveguide cover or other replacement part?
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