Kenmore Oven Error Code F82

The F82 error code on a Kenmore oven indicates a microwave thermistor open error. The thermistor is a temperature-sensing resistor located in the microwave cavity. When the control board cannot read a valid temperature signal from this sensor, it triggers F82. This can happen either because the thermistor itself has failed or because the convection heating element has stopped generating heat, leaving the cavity temperature outside the expected range.

The convection element in a combination microwave-oven unit is central to this fault. The control board monitors cavity temperature during convection cooking cycles and expects a measurable rise in temperature. If the element is not functioning, the thermistor never detects a temperature increase, and the board interprets this as a sensor open condition. The first diagnostic step is to run a convection function and physically verify whether the element heats. The convection element should measure approximately 10.2 ohms between its terminals when tested with a multimeter. A reading that is open (infinite resistance) or significantly out of spec confirms element failure.

If the element tests within spec, the fault lies in the thermistor circuit itself. An open thermistor will show no continuity or an extremely high resistance reading compared to its rated value. Wiring connections between the thermistor and the control board should also be inspected for breaks, corrosion, or loose terminals. In cases where wiring and the thermistor both test correctly, the control board may be misreading the sensor signal and could require replacement.