Dual-fuel range oven shows E18 and the cooling fan runs continuously even when the oven is off.

Safety first: Disconnect power before accessing the rear of the range or control panel. Allow the oven to cool fully.

Steps:

• Verify actual temperature: Ensure the oven cavity and control area are at room temperature. If the fan still runs with a cold oven, a control issue is likely.
• Check sensor reading: Test the oven temperature sensor resistance at the control board connector. If it reads as if the oven is hot (low resistance) when cold, replace the sensor.
• Inspect wiring: Check the cooling fan wiring harness for shorts to line voltage that could power the fan directly.
• Control board replacement: If the sensor and wiring are good, the cooling fan relay on the control board may be welded closed. Replace the electronic oven control.

Note: A continuously running fan can shorten fan life and indicate an underlying overheating issue that should be addressed.