Unox WF04 Error Code
Fan speed error (grouped with AF08).
Source: Unox/Unox_XACC-0513-EPLM_ServiceManualAll_CommercialKitchen.pdf
What does Unox WF04 mean?
WF04 is a fan speed error, listed with AF08. The oven monitors the cooking chamber fan speed and has detected that the fan is not running at the expected speed. As a warning it allows limited operation while signalling that air circulation may be impaired, which affects cooking uniformity.
Symptoms
- WF04 warning on the control panel
- Fan running slow, fast or not at the commanded speed
- Uneven cooking results
- Warning recurs during operation
Common causes
- Fan motor fault or wear
- Motor drive or control fault
- Tachometer / speed feedback fault
- Mechanical obstruction of the fan
- Wiring fault to the motor or feedback sensor
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Diagnostic steps
Power down and check the fan
Turn off power and check the chamber fan turns freely without obstruction.
Verify the motor runs
Confirm the fan motor runs at the commanded speed when the oven operates.
Check speed feedback
Verify the speed/tachometer feedback signal reaches the board so it can read actual fan speed.
Test wiring and components
Inspect the motor and feedback wiring and replace the motor or sensor if the speed cannot be read or maintained.
When to call a professional
WF04 involves the fan motor, its drive and speed feedback. Testing these and replacing the motor requires mains-voltage work inside the oven. If a quick obstruction check does not clear it, have a qualified Unox technician diagnose the fan drive and feedback.
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Other Unox Error Codes
Motor thermal protection alarm (permanent error) — the fan motor's thermal protection has tripped.
Safety thermostat alarm — the chamber safety thermostat has tripped above its limit.
Temperature probes alarm — a cooking chamber temperature probe is damaged or disconnected.
Communication error with the power board — the control board lost communication with the power board.
Gas alarm — a fault in the gas burner/ignition system (split into multiple AF23 conditions on later software).
Wrong position of Pollo valve.
Trolley is missing.
Tank missing or safety thermostat fault.
Chamber ceiling temperature too high.
Chamber over-temperature condition (Case 1: T > 150 °C / 302 °F; Case 2: T < 150 °C).
Single-point or multi-point core probe completely damaged.
Chamber temperature probe warning.