Thermador Oven Error Code E118

E118 indicates a cooling fan supervision error in the upper or single oven cavity. The control board has detected that the cooling fan speed is either too low or too high compared to the expected operating range. This fault is monitored through a Hall Effect Sensor that tracks fan rotation speed. The error points to a wiring issue, a mechanical obstruction, a faulty sensor, or a failing fan motor.

It is not recommended to continue using the oven while E118 is active. The cooling fan protects the oven's electronic control components from heat buildup during and after cooking cycles. Operating without a properly functioning cooling fan risks overheating the control board and other internal parts, which can lead to more extensive and costly damage.

Repair costs depend on which component is at fault. If the issue is a simple wiring adjustment or connector reseat, there may be no parts cost and only a service call fee, which typically ranges from $75 to $150. Replacing the Hall Effect Sensor or fan motor will add parts costs, and total repair bills for those scenarios commonly range from $200 to $500 or more depending on labor rates in your area.

Some causes of E118 can be addressed without replacing parts. Checking that the wire harness is not pinched or contacting the motor, confirming the plenum is not touching the fan end cap, and reseating the Hall Effect Sensor connector are all steps a skilled DIYer can perform. If those checks do not resolve the fault, replacing the sensor or fan motor will require comfort with appliance disassembly and electrical components.

A power reset by turning off the circuit breaker for 30 to 60 seconds may temporarily clear the code, but it will return if the underlying fault is not corrected. The control board will resume monitoring fan speed as soon as the oven is powered and operated again, and any mechanical or electrical issue causing the fault will trigger E118 again.