Cooker
F04
The F04 error code on a Zanussi cooker indicates a fault with the oven temperature sensor (NTC probe), meaning the appliance cannot accurately read the oven cavity temperature. It’s a moderately serious fault — the oven will typically stop heating or refuse to start until it’s resolved.
What does this error mean?
F04 signals that the oven’s NTC (Negative Temperature Coefficient) temperature sensor is returning a reading that’s outside the expected range — either an open circuit, a short circuit, or a wildly incorrect temperature value. The cooker’s control board detects this as a safety issue and shuts down the heating element to prevent overheating or underheating. In short, the oven doesn’t trust its own thermometer, so it won’t operate.
Est. repair cost
£15–£35 DIY NTC sensor replacement; £80–£150 professional repair; £150–£250 if control board replacement is needed
🔍 Likely causes
🛠️ Step-by-step fix
Step 1 – Reset the cooker: Switch the appliance off at the wall socket (or flip the circuit breaker), wait 5 minutes, then power it back on. If F04 clears and doesn’t return, it was a temporary glitch.
Step 2 – Check the oven cavity visually: With the oven cold and unplugged, look inside the oven for the NTC probe — it’s usually a small metal pin or rod mounted on the back or side wall. Check it’s seated firmly and hasn’t physically broken away from its bracket.
Step 3 – Inspect the sensor wiring (with the oven unplugged and fully cold): Gently pull the oven away from the wall and remove the back panel (usually 4–6 screws). Look for any burnt, pinched, or disconnected wires leading from the sensor to the main harness. Reconnect any loose spade connectors firmly.
Step 4 – Test or replace the NTC sensor: A working Zanussi NTC sensor typically reads around 1,000 ohms (1kΩ) at room temperature using a multimeter set to resistance. A reading of 0 (short) or OL/infinite (open circuit) confirms sensor failure. Replacement sensors cost £15–£35 and are available from UK parts suppliers such as eSpares or BuySpares — match the part number from your model’s rating plate.
Step 5 – Refit and test: Reassemble, restore power, and run the oven at 180°C for 10 minutes to confirm the error is gone and the oven heats correctly.
Step 6 – If F04 persists after a confirmed working sensor: The fault lies with the control board or wiring loom — stop here and call a qualified appliance engineer, as PCB diagnosis and replacement is not a safe DIY task.
📞 When to call a professional
Call a qualified appliance repair engineer if the error persists after replacing the NTC sensor, or if you find burnt wiring anywhere in the appliance. Tell them: ‘My Zanussi electric cooker is showing error code F04 — I’ve checked the NTC sensor and suspect either a wiring loom fault or a PCB issue.’ Attempting to repair or bypass a control board without the correct tools and knowledge risks electric shock and further damage.
⚖️ Repair or replace?
A professional repair — including diagnostics, NTC sensor or wiring fix — typically costs £80–£150 in the UK. If the control board needs replacing, expect £150–£250 parts and labour. For any Zanussi cooker over 8–10 years old where the repair cost exceeds 50% of a new equivalent model (budget built-in ovens start around £250–£350), replacement is the more sensible financial decision. For a newer appliance still under warranty, contact Zanussi customer service before spending anything.