Whirlpool Microwave Error Code NTC OPEN

NTC OPEN means the control board has detected an open circuit in the HF NTC thermistor, which is the temperature sensor that monitors the high-frequency components including the magnetron. The display scrolls the message 'NTC OPEN, CALL FOR SERVICE' to alert you to the fault. The microwave shuts down as a protective measure because it can no longer monitor component temperatures. The thermistor's expected resistance is 10k ohms, plus or minus 5%, at 77 degrees Fahrenheit.

No, the microwave should not be used while this error is active. The NTC thermistor is a safety component that protects against overheating, and the unit will not operate normally while the fault is present. Attempting to bypass the error without repairing the underlying cause could risk damage to internal components.

Unplugging the microwave and restoring power may temporarily clear the display, but the error will return as soon as the control board checks the thermistor circuit again and detects the open condition. A reset does not fix the underlying hardware fault. The thermistor or its wiring must be repaired or replaced for the error to clear permanently.

A knowledgeable DIYer can begin by unplugging the microwave and measuring the HF NTC thermistor with a multimeter to confirm whether the component has failed. If the thermistor reads open or far outside the 10k ohm specification, replacing it is a straightforward parts swap. However, microwaves contain high-voltage capacitors that can retain a dangerous charge even after unplugging, so proper discharge procedures must be followed before touching internal components.

If only the thermistor needs replacement, parts costs are generally in the range of $10 to $40 depending on the specific model. If a professional technician is needed, expect total repair costs including labor to fall somewhere between $80 and $200. Control board replacement, if required, can push costs higher and may factor into a repair-versus-replace decision.