Oven
F34
The F34 error code on an AEG oven signals a fault with the oven’s core temperature sensor circuit — it’s a moderate fault that will prevent the oven from heating safely until resolved.
What does this error mean?
F34 indicates that the oven’s internal temperature sensor (NTC probe) is reading a value outside the expected range — either an open circuit (no signal) or a short circuit (constant signal). The oven’s control board cannot confirm the cavity is at a safe temperature, so it locks out the heating elements as a precaution. This is a built-in safety feature, not a sign that the oven has burned out, and the fix is often straightforward.
Est. repair cost
DIY sensor replacement: £15–£35 for the part. Professional repair: £80–£200 including call-out and labour.
🔍 Likely causes
🛠️ Step-by-step fix
Power reset first: Switch the oven off at the wall socket (or trip the circuit breaker), wait 5 minutes, then restore power. If F34 clears and the oven heats normally, it was a transient glitch — monitor it for recurrence.
Check the oven door seal and cavity for obvious signs of water ingress or heavy grease build-up near the rear wall, where the sensor probe is typically located. Clean with a damp cloth (oven fully cold and unplugged).
Locate the NTC sensor: it is usually a small metal probe mounted through the rear inner wall of the oven cavity, held by one or two screws, with a two-wire connector. Visually inspect the connector for corrosion, burning marks, or a loose fit — unplug and firmly reseat it.
Test the NTC sensor resistance with a multimeter (oven unplugged): at room temperature (~20°C) a healthy AEG NTC sensor typically reads approximately 10,000 ohms (10kΩ). A reading of zero (short) or infinite (open circuit) confirms a failed sensor — replace it.
Order a genuine AEG replacement NTC sensor using your oven’s full model number (found on the rating plate inside the door frame). Fit it by reversing removal — unscrew the old probe, disconnect the wiring, connect and screw in the new one. No specialist tools required.
If the error persists after a confirmed good sensor is fitted, the control board (PCB) is likely at fault — do not attempt to repair the PCB yourself. At this point, call an appliance engineer.
📞 When to call a professional
Call a qualified appliance engineer if F34 returns after you have replaced the NTC sensor, or if you find burnt or melted wiring in the oven cavity — do not use the oven until it has been inspected. When booking, tell the engineer: ‘My AEG oven is showing error code F34 — I suspect either the NTC temperature sensor circuit or the control board.’
⚖️ Repair or replace?
A professional repair (engineer call-out, sensor or PCB replacement) typically costs £80–£200 in the UK depending on the part needed. If your AEG oven is under 8 years old, repair is almost always the better value; AEG electric ovens retail from around £400–£700 new. If the oven is over 10 years old and the PCB needs replacing (parts can be £100–£180 alone), replacement may make more financial sense.