A02 High
Your boiler detects a flame when it should be turned off, which prevents the system from starting up safely.
Technical description: Flame signal present with burner off
Typical repair cost: £120-280 (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
- Main control board
- Gas valve
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