Microwave runs but does not heat food; turntable, light, and fan operate normally but items remain cold.

Critical safety warning: The high-voltage section of a Viking microwave can store lethal energy. Do not attempt to test or replace the magnetron, capacitor, diode, transformer, or inverter unless you are trained and equipped.

• Basic checks: Confirm that you are using a microwave-safe container and that the cook time and power level are set correctly. Test with a cup of water for 1–2 minutes.
• Listen and observe: During operation, listen for the normal hum of the magnetron/transformer. If the unit is unusually quiet or makes a loud buzzing, internal HV components may be failing.
• Check door function: Ensure the door closes properly and that the interior light and fan come on when cooking starts. If they do not, the issue may be with door switches instead of the HV system.
• Professional service: For no-heat conditions with normal operation otherwise, have a Viking-authorized technician test the magnetron, HV diode, capacitor, and transformer/inverter.
• Component replacement: Common repairs include replacing the Viking magnetron and/or high-voltage diode. Always use OEM parts and verify proper grounding and shielding after repair.