Likely Causes
A failed magnetron
A failed magnetron. This is one of the more frequent reasons homeowners in our service area call about this exact symptom.
A blown high-voltage diode or capacitor
A blown high-voltage diode or capacitor. This is one of the more frequent reasons homeowners in our service area call about this exact symptom.
A faulty door interlock switch
A faulty door interlock switch. This is one of the more frequent reasons homeowners in our service area call about this exact symptom.
Safe Checks You Can Try First
- Confirm the door is closing and latching fully
- Test with a cup of water for 30 seconds to confirm the no-heat issue is consistent
- Avoid repeated attempts — do not open the unit yourself; components carry high voltage
When to Call a Technician
No-heat issues should always be diagnosed by a technician due to the high-voltage components involved.
Frequently Asked Questions
No — most cases like this are a specific, repairable part failure rather than a sign the whole unit needs replacing. A technician can tell you the realistic cost-versus-replace comparison on the spot.
The checks above are safe to try yourself. Beyond that, appliance repair involves electrical, gas, or refrigerant systems that are best left to a trained technician.