Dacor Range, Oven, Cooktop Error Code U34

U34 means the control board has detected an open circuit in RTD 3, the temperature sensor for the upper or single oven cavity. An open circuit means the sensor signal is completely lost, so the oven cannot monitor its internal temperature. The code directs technicians to start by checking the wiring at all connection points in the RTD 3 circuit.

No, you should not attempt to use the oven while U34 is active. Because the control board cannot read oven temperature, it cannot regulate heating properly, which creates a risk of overheating. Stop using the oven until the sensor circuit is repaired.

Resetting the oven by cycling power may temporarily clear the U34 display, but the code will return immediately or as soon as the oven tries to read the sensor if the underlying fault is still present. A reset does not fix an open circuit in the RTD wiring. The physical cause must be diagnosed and corrected for the error to stay cleared.

If you are comfortable working with appliance wiring, you can inspect and reseat the RTD sensor connectors yourself, which resolves the fault in many cases. Testing the sensor with a multimeter for continuity is also a straightforward step. However, if the harness is damaged or the sensor needs replacement, some comfort with appliance disassembly is required, and a technician may be advisable if you are unsure.

If only a connector needs reseating or cleaning, there may be no parts cost at all, though a service call fee would still apply if you hire a technician. Replacing the RTD temperature sensor typically costs between $50 and $150 for the part alone, with labor adding to the total. A control board replacement, if needed, is considerably more expensive, often ranging from $200 to $500 or more for the part.