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AF26Unox

Unox AF26

Tank missing or safety thermostat fault.

Source: Unox/Unox_XACC-0513-EPLM_ServiceManualAll_CommercialKitchen.pdf

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What does Unox AF26 mean?

AF26 indicates the tank is missing or there is a safety thermostat fault associated with it. The oven has detected that a required tank is not present (or not correctly read) or that its safety thermostat has tripped, and it stops to protect the appliance.

Symptoms

  • AF26 shown on the control panel
  • Oven stops or blocks the affected function
  • Alarm clears when the tank is correctly fitted
  • Recurring alarm after overheating

Common causes

  • Tank not fitted or not correctly seated
  • Tank safety thermostat tripped by overheating
  • Faulty tank-presence detection
  • Wiring fault to the tank thermostat or sensor

Diagnostic steps

  1. 01

    Check the tank is fitted

    Confirm the tank is correctly installed and seated, then retry the operation.

  2. 02

    Allow cooling and check the thermostat

    If overheating is suspected, let the assembly cool and check the related safety thermostat.

  3. 03

    Test presence and thermostat circuits

    With power off, verify the tank-presence detection and the safety thermostat continuity with a multimeter.

  4. 04

    Repair wiring or replace the part

    Restore any faulty wiring and replace the thermostat or sensor if it does not test correctly.

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When to call a professional

AF26 combines a presence check with a safety thermostat, so it can indicate a real over-temperature condition. Testing the thermostat and presence circuits requires opening the oven and mains-voltage measurement. If fitting the tank correctly does not clear it, have a qualified Unox technician investigate the safety circuit.

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