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HomeRepair HelpThermador Microwave RepairThermador Microwave producing a burning smell Repair
Thermador Microwave producing a burning smell
If your Thermador 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 and create a microwave burning smell. Next, inspect the power supply board for burn marks or a shorted component. A failing high-voltage capacitor or capacitor can overheat and produce a burning smell, and a damaged thermostat may also show heat or burn damage. Finally, check the interior cavity for spilled food or grease. Food debris can continue cooking each time the microwave runs, causing a burning smell from the microwave, so clean the cavity thoroughly and cover food to prevent splatter. Replace a damaged waveguide cover or other failed part with the correct Thermador component. Repairs involving the high-voltage capacitor, high-voltage diode, magnetron, high-voltage transformer, or any repair requiring removal of the outer cabinet require caution because the high-voltage capacitor can store a lethal charge even after the microwave is unplugged. It must be properly discharged before interior work, and a qualified technician should handle the repair if you are not familiar with capacitor discharge procedures. Enter your model number to find the exact replacement part for your Thermador microwave.
01 - Thermador 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 - Thermador 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 - Thermador 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 - Thermador 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 - Thermador 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 Thermador microwave smell like burning?
Can I keep using a Thermador microwave with a burning smell or sparks?
How do I know if the microwave waveguide cover is causing the burning smell?
Could a high-voltage capacitor, power supply board, or thermostat cause a Thermador microwave burning smell?
How do I find the correct Thermador microwave waveguide cover or other replacement part?
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