Viking Designer Cooktop Code FU: Another Key Error Stops the Elements

What FU means

On Viking Designer DETU series touch-control radiant cooktops, FU is a key error. The control stops all heating elements and shows FU on the timer display. A touch key may be reading as pressed or a key circuit may be failing. It carries the same key error meaning as FA, FC and FJ, though each letter points at a different key circuit, so be exact when you describe it.

Common causes of FU

Touch key reading as pressed
Moisture or residue on the panel
Panel circuit sending a false press

✓ One safe check you can try

1. Turn the cooktop off and let it cool. 2. Dry the panel and take away anything on it. 3. Switch the breaker off for one minute and on again. 4. Touch the on key once. 5. If FU returns, call us.

! Why to stop there

The keys are beneath the glass
A returning key error points to a worn circuit
Technicians test each key circuit separately

Opening a panel yourself does not automatically cancel a manufacturer warranty, but it can cause accidental damage, and some manufacturers set their own service conditions. Check your warranty terms, or ask us, before deciding.

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Other Cooktop codes

10Viking Induction Cooktop Code 10: wrong terminal connected, supply over 400 volts Residual HeatViking Induction Cooktop Message "Residual Heat": zone still above 60 C Er31Viking Induction Cooktop Code Er31: Wrong Interface Board Fitted F5Viking Designer Cooktop Code F5: Communication Error That Stops All Heat FAViking Designer Cooktop Code FA: Key Error Shuts Off the Elements FbViking Designer Cooktop Code Fb: Keyboard Error With a Small b FCViking Designer Cooktop Code FC: Key Error With a Capital C FcViking Designer Cooktop Code Fc: Over Temperature With a Small c

FUFU questions

Does FU mean the glass is broken?

No. It points to a key circuit, not to cracked glass. If the glass is cracked, switch the cooktop off at the breaker and call us immediately.

Why does a key error stop all heat?

If the control cannot trust the keys, it cannot be sure what you want. It cuts the elements as a precaution. Once the keys read normally, heating resumes.

What is the repair like?

We test the key circuits, replace the control or panel if needed, and verify every zone. The price is written first and the repair has a 30-day workmanship warranty. We give you a written price before any work and the repair carries a 30-day warranty.