Dacor Range, Oven, Cooktop Error Code U31

U31 indicates a shorted RTD 1 condition, meaning the upper or single oven temperature sensor circuit is reading an abnormally low resistance that the control board interprets as a short circuit. The sensor, designated RTD 1, is the primary temperature probe for the oven cavity. The control board disables normal operation when this fault is detected to prevent uncontrolled heating. The fault points to either a wiring problem in the sensor circuit or a failed sensor probe.

You should not attempt to use the oven while U31 is active. A shorted temperature sensor means the control board cannot accurately monitor the oven cavity temperature, which removes a critical safety safeguard against overheating. Operating the oven in this condition is not recommended until the sensor circuit has been repaired and verified.

A power reset, such as switching off the circuit breaker for 60 seconds, may temporarily clear the U31 code, but it will return if the underlying fault in the sensor circuit is not repaired. Because U31 reflects an actual measured electrical condition (a short in the RTD circuit), the error will reappear once the control board runs its diagnostics again. A reset alone is not a fix and the sensor wiring and probe should be inspected before returning the oven to service.

A knowledgeable DIYer can address this fault by starting with a visual inspection of the sensor wiring harness and connector points, which are the most likely cause. If the wiring looks intact, testing the RTD sensor with a multimeter to check its resistance is a straightforward next step. Replacing the sensor probe is generally accessible from inside the oven cavity. However, if the fault traces back to the control board, professional repair is recommended.

If only the RTD temperature sensor needs replacement, parts and labor typically run in the range of $100 to $250 depending on the specific model and local labor rates. If the wiring harness requires repair or replacement, costs can vary widely based on the extent of the damage. A control board replacement, if needed, is generally the most expensive outcome and can range from $300 to $600 or more including installation.