Thermador Hood Error Code Three speed LEDs blinking

All three speed LEDs blinking simultaneously on a Thermador hood indicates a heat sensor protection fault. The heat sensor, which is integrated into the input board, has failed or is producing a signal outside of acceptable parameters. This fault puts the hood into a protected state to prevent operation without functional thermal monitoring. The input board must be replaced to resolve the error.

Continued use is not recommended when this fault is active. The blinking LEDs indicate that the heat sensor protection circuit is no longer functioning, which means the hood's built-in thermal safeguard is inactive. Without this protection, the hood electronics could be exposed to damaging temperatures during cooking without any automatic response. It is best to discontinue use until the input board is replaced.

No, resetting the hood by cutting power will not permanently clear this fault. The error is caused by a physically damaged heat sensor that is part of the input board, so the fault condition will return as soon as the hood powers back on and the control system detects the same faulty sensor signal. The only way to resolve this error is to replace the input board with a functioning unit.

The repair requires replacing the input board, which is an intermediate to advanced task. The heat sensor is built into the board and cannot be replaced on its own, so the full board assembly must be sourced and installed. If you are comfortable working with appliance electronics and can safely disconnect power before servicing, this is a possible DIY repair. However, many homeowners choose to have a qualified technician handle this to ensure the board is installed correctly.

Repair costs will vary depending on the specific input board part and labor rates in your area. Parts alone for a Thermador hood input board typically fall in the range of $80 to $250 or more depending on the model. If you hire a technician, labor charges will add to that cost, bringing the total repair estimate to somewhere between $150 and $450 in most cases. Getting a quote from a local appliance repair service before proceeding is advisable.