Thermador Range Error Code F33

F33 indicates either an upper oven over-temperature condition detected while cooking, or a failure in the warming drawer temperature sensor circuit. The control board triggers this code as a protective measure when the upper oven exceeds safe temperature limits, typically above 550 degrees Fahrenheit, or when it loses a valid signal from the warming drawer sensor. Diagnosing which condition applies requires checking sensor resistance and the P3 header connection before evaluating the power and relay board.

A power reset may temporarily clear the F33 display, but it will not fix the underlying cause. If the oven is still above 550 degrees Fahrenheit when power is restored, the code will immediately return. Even if the fault clears after cooling, it will reappear the next time the oven is used if the sensor, wiring, or relay board issue is not addressed. A reset is only useful as a first step to confirm whether the fault is intermittent or persistent.

Repair costs vary depending on which component has failed. A replacement temperature sensor typically runs between 30 and 80 dollars for the part, while a power and relay board can cost anywhere from 150 to 400 dollars or more depending on the model. Adding professional labor, total repair costs commonly range from 150 to 500 dollars. If the fault is simply a loose connector at P3, the repair may cost nothing beyond a service call if a technician is involved.

No, you should not continue cooking when F33 is active. The code indicates either a genuine over-temperature event or a sensor failure that prevents the oven from accurately monitoring its own temperature. Either condition means the oven cannot regulate heat safely until the underlying fault is diagnosed and corrected. Turn the range off and allow it to cool completely before any further use or inspection.

Start by allowing the oven to cool below 550 degrees Fahrenheit, then restore power and check whether the code returns. Inspect the P3 header connector on the control board for loose or corroded contacts and reseat it if necessary. Test the temperature sensor resistance, which should read approximately 1080 ohms at room temperature; replace the sensor if it reads outside this range. If the sensor and connections are both good, the power and relay board is likely the faulty component and should be replaced.