A02 High
Your boiler thinks it sees a flame even though it hasn't started the burner yet, which is causing it to shut down for safety.
Technical description: Flame detected with the burner off – possibly caused by ionisation, defective electrode or main board defective. Check the printed circuit board (PCB) or ionizing electrode wiring
Typical repair cost: £120-350 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Protect yourself from future repair bills
A boiler cover plan would cover faults like A02 — no call-out fees, no surprises.
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Parts commonly replaced
- Ionisation Electrode
- Control PCB
- Electrode Wiring
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