What does Unox AF01 mean?

AF01 is a permanent motor thermal protection alarm. The fan motor that circulates air in the cooking chamber has overheated and its internal thermal protection circuit has opened, stopping the oven.

What does Unox AF02 mean?

AF02 is the safety thermostat alarm. The oven's safety thermostat, which trips around 320 °C (608 °F), has opened because the cooking chamber overheated, and the oven is locked in STOP. It protects the appliance when the normal temperature control fails to limit chamber temperature.

What does Unox AF03 mean?

AF03 is the chamber temperature probes alarm. The control board has lost a valid reading from a cooking chamber temperature probe — typically because the probe is disconnected, out of range, or failed — so the oven stops to avoid uncontrolled heating. The chamber probes connect to sockets P19 (CMB1) and P16 (CMB2).

How do I maintain a Unox unit?

Follow the Unox recommended maintenance schedule: daily cleaning of accessible surfaces, weekly inspection of seals and gaskets, monthly check of electrical connections and water filters, and annual professional service including calibration and safety checks.

Where can I find Unox parts and documentation?

Genuine Unox replacement parts and service documentation are available through authorised dealers. For instant answers about Unox troubleshooting and maintenance, use AskWhiz on WhatsApp.

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What error codes does Unox display?

AF01

Motor thermal protection alarm (permanent error) — the fan motor's thermal protection has tripped.

AF02

Safety thermostat alarm — the chamber safety thermostat has tripped above its limit.

AF03

Temperature probes alarm — a cooking chamber temperature probe is damaged or disconnected.

AF04

Communication error with the power board — the control board lost communication with the power board.

AF23

Gas alarm — a fault in the gas burner/ignition system (split into multiple AF23 conditions on later software).

AF24

Wrong position of Pollo valve.

AF25

Trolley is missing.

AF26

Tank missing or safety thermostat fault.

AF39

Chamber ceiling temperature too high.

AF41

Chamber over-temperature condition (Case 1: T > 150 °C / 302 °F; Case 2: T < 150 °C).

AF43

Single-point or multi-point core probe completely damaged.

WF01

Chamber temperature probe warning.

Common questions about Unox equipment

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