Narrow it down
What this symptom can tell you
Runs normally but stays cold
A setting, demo mode, door condition, or internal high-voltage component may be involved.
Heats slowly
Low power level, unsuitable cookware, oversized load, or supply issues may reduce heating.
Works intermittently
Door alignment, overheating, control, or internal faults may require service.
These observations narrow the next safe check; they do not confirm a failed part. Use the full model number and any displayed code before ordering parts or authorizing repair.
Try these checks in order
Stop when a step does not match your appliance, the exact manual, or your comfort level.
- 1
Confirm cooking time and power
Select a normal cook cycle at full power rather than Timer, Keep Warm, or a low power level.
What you want: The display shows a cooking cycle and full power. - 2
Check demo mode or showroom mode
Use the exact manual to turn off any demo setting.
What you want: The appliance exits demo mode. - 3
Close the door without force
Remove debris and confirm the door sits flat. Do not operate with a damaged latch or seal.
What you want: The door closes normally with no visible damage. - 4
Use microwave-safe cookware
Remove metal, foil, or containers not approved for microwave use.
What you want: The container is labelled microwave safe. - 5
Run one controlled water test
Place one cup of water in a microwave-safe container and heat it briefly according to the manual. Never run the microwave empty.
What you want: The water becomes noticeably warmer.
Possible categories
What may be causing the problem
- Timer-only, low-power, demo, or sensor settings.
- Door alignment or interlock conditions.
- Unsuitable cookware or an unusually large or frozen load.
- A magnetron, high-voltage, control, sensor, power, or cooling fault requiring qualified service.
Stop and arrange help when
- The door, latch, seal, window, or cabinet is damaged.
- The microwave sparks, smokes, smells burned, or trips the breaker.
- It makes a loud buzzing, arcing, or grinding sound.
- It still does not heat after the safe external checks.
If the problem remains
Record the full model number, exact symptom, displayed code, and the safe checks completed. Then use official brand support or qualified service.
Outcome check
Did these checks resolve the problem?
Your answer helps identify which guides need improvement. No appliance details are submitted.
Common questions
Microwave not heating food: FAQs
Why does my microwave run but not heat?
A setting or demo mode can mimic normal operation, but internal high-voltage faults can also allow lights and fans to run without heating.
Can I open the microwave cabinet?
No. Internal high-voltage components may remain hazardous after the appliance is unplugged.
Is it safe to test a microwave empty?
No. Use a microwave-safe cup of water if the exact manual recommends a heating test.
Research and verification
Source basis
This guide is limited to external, owner-safe checks and was reviewed against official manufacturer or government resources. The exact model manual takes priority.