What U30 / L30 Means
U30 or L30 means the oven temperature sensor (RTD) of the upper or lower oven reads open. Dacor’s guide calls it a fatal error: the control sees readings above its maximum bounds and will not heat that oven. The guide’s check is a resistance of roughly 1,050 to 1,100 ohms at room temperature across the sensor.
Common Causes of U30 / L30
- RTD sensor failed open after years of self-clean heat
- Sensor wire broken or pinched behind the cavity
- Sensor connector at the control unseated
🔧 One Safe Check You Can Try
With the oven cool, check that the sensor probe inside the cavity is not bent or broken. A breaker reset is worth one try, but a sensor that reads open will bring the code straight back.
⚠ Why You Shouldn't Go Further Than That
- The sensor connects at the back of the control, which is reached with the oven out of the cabinet.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.