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Error code reference

Thermador Range Error Code F15

Relay board sensor shorted (Gaggenau EB 270/271/290/291).

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What the F15 error code actually means

Your oven has detected an electrical problem on one of its internal control boards, specifically a short circuit in a sensor circuit on the relay board. This safety feature shuts the oven down to prevent further damage. A technician will need to replace the relay board to get the oven working again.

Diagnostic procedure

The full F15 procedure

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First diagnostic step
Replace relay board.
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Most common causes of F15

Ranked by how often they cause this code
  1. 1Failed relay board with internal sensor short
  2. 2Moisture or liquid intrusion on the relay board
  3. 3Heat damage to relay board circuitry
  4. 4Damaged or pinched wiring harness causing external short

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Questions people ask about F15

What does F15 mean on a Thermador range?
F15 on a Thermador range indicates a shorted sensor on the relay board. This fault applies specifically to Gaggenau EB 270, 271, 290, and 291 model variants. The oven's control system has detected an abnormal short circuit condition within the relay board's sensor circuit and has halted operation as a protective measure.
Is it safe to use my Thermador range while it shows F15?
No, you should not attempt to operate the oven while the F15 code is active. The fault indicates a short circuit condition within the relay board, which could lead to component damage or unpredictable oven behavior. Disconnect power to the range until the relay board has been inspected and replaced.
How much does it cost to fix a Thermador range F15 error?
Repair costs typically depend on the price of the relay board part and labor rates in your area. Parts for specialty European-style ranges like the Gaggenau EB series can range from around $150 to $400 or more, and professional labor can add another $100 to $250 depending on the technician and region. Getting a diagnostic quote from an authorized technician before committing to the repair is advisable.
Can I fix the F15 error myself on a Thermador range?
The repair requires replacing the relay board, which involves working with high-voltage oven components. A qualified appliance technician is strongly recommended for this repair. An experienced DIYer comfortable with appliance electronics could attempt it after disconnecting power at the breaker, but sourcing the correct relay board for the specific EB model variant is essential.
Will resetting the oven clear the F15 error code?
A power reset by turning off the breaker for several minutes may temporarily clear the code, but it will return once the oven attempts to operate because the underlying short circuit in the relay board remains present. A reset does not fix the hardware fault and is not a reliable solution.

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