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HomeRepair HelpUniversal Microwave RepairUniversal Microwave producing a burning smell Repair
Universal Microwave producing a burning smell
When an Universal microwave smells like burning, stop using it until you identify the cause. The most likely problem is a damaged or loose waveguide cover, which can arc and produce a burning smell. 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, and a defective thermostat may also show heat damage. Do not overlook the simplest cause: food debris or splattered grease inside the cavity can continue cooking and create a burning smell, so clean the interior thoroughly and replace the waveguide cover if it is damaged or will not stay in place. If the smell is like burning plastic, rubber, or wires, unplug the microwave and arrange a repair before using it again. Replacing a waveguide cover or thermostat may be manageable, but any repair involving the high-voltage capacitor, high-voltage diode, transformer, power supply board, or opening the outer cabinet requires caution. The capacitor can store a lethal charge even after the microwave is unplugged and must be properly discharged. Use a qualified technician if you are not familiar with capacitor discharge procedures. Enter your model number to find the exact replacement part for your specific Universal microwave.
01 - Universal 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 - Universal 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 - Universal 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 - Universal 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 - Universal 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 microwave smell like burning?
What should I do if my microwave smells like burning plastic or burning wires?
Can a damaged microwave waveguide cover cause a burning smell?
How do I test a microwave capacitor or power supply board after a burning smell?
How do I find the correct replacement waveguide cover or other microwave part?
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