Thermador Oven Error Code F5

F5 on a Thermador oven means the element supervisor for the single or upper oven has been disabled by the control system. This happens when the control detects an intermittent or unreliable signal from the oven temperature sensor. The code is a safety response that prevents uncontrolled heating when accurate temperature monitoring cannot be confirmed. The two components to investigate are the upper oven temperature sensor and the main relay board.

No, it is not recommended to continue using the oven while F5 is active. The error indicates that temperature supervision has been disabled, meaning the control cannot reliably monitor or regulate oven cavity heat. Operating the oven in this condition creates a risk of uncontrolled heating. The oven should remain off until the faulty component is diagnosed and replaced.

Repair costs vary depending on which component is at fault. A replacement upper oven temperature sensor typically ranges from $20 to $80 in parts. A main relay board is a more expensive component, generally ranging from $150 to $400 or more depending on the model. Adding professional labor costs, a full relay board replacement repair can range from $250 to $600 or higher. Replacing the sensor yourself, if it resolves the issue, is the most cost-effective outcome.

A knowledgeable DIYer can attempt to replace the upper oven temperature sensor, which is typically the first and most accessible repair step. If that does not clear the code, replacing the main relay board is a more involved repair that requires careful handling of electrical components and is often best handled by a qualified technician. Always disconnect power to the oven before performing any component inspection or replacement.

Resetting the oven by cutting power at the circuit breaker for a few minutes may temporarily clear the F5 code, but the error will almost certainly return if the underlying fault has not been corrected. Because F5 is triggered by an intermittent sensor or relay board failure, the code will reappear once the control detects the same unreliable temperature signal again. A proper repair requires replacing the defective component.