Unox AS04
Static oven floor/ceiling temperature probe alarm (with AS05).
Source: Unox/Unox_XACC-0513-EPLM_ServiceManualAll_CommercialKitchen.pdf
What does Unox AS04 mean?
AS04 (listed with AS05) is a floor/ceiling temperature probe alarm on the static oven accessory. A temperature probe measuring the floor or ceiling has failed or is disconnected, so the static oven stops to avoid uncontrolled heating. The main oven can still be used.
Symptoms
- AS04 shown referencing the static oven
- Static oven will not heat correctly
- Implausible floor/ceiling temperature reading
- Alarm persists across restarts
Common causes
- Floor or ceiling probe disconnected
- Probe out of range or failed
- Wiring fault to the probe
- Connector problem
Diagnostic steps
- 01
Power down and check the probe
Turn off power and confirm the floor/ceiling temperature probe is connected.
- 02
Measure the probe
Measure the probe with a multimeter to confirm it is within range.
- 03
Inspect the wiring
Check the wiring between the probe and the static oven board.
- 04
Replace the probe
Replace the temperature probe if it is out of specification and retest.
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When to call a professional
AS04 affects the static oven accessory. Confirming the probe and wiring requires accessing the accessory; have a qualified Unox technician verify and replace the probe if reconnecting it does not clear the alarm.
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Open a ticket — free accountOther Unox error codes
Motor thermal protection alarm (permanent error) — the fan motor's thermal protection has tripped.
AF02Safety thermostat alarm — the chamber safety thermostat has tripped above its limit.
AF03Temperature probes alarm — a cooking chamber temperature probe is damaged or disconnected.
AF04Communication error with the power board — the control board lost communication with the power board.
AF23Gas alarm — a fault in the gas burner/ignition system (split into multiple AF23 conditions on later software).
AF24Wrong position of Pollo valve.
AF25Trolley is missing.
AF26Tank missing or safety thermostat fault.
AF39Chamber ceiling temperature too high.
AF41Chamber over-temperature condition (Case 1: T > 150 °C / 302 °F; Case 2: T < 150 °C).
AF43Single-point or multi-point core probe completely damaged.
WF01Chamber temperature probe warning.