High Lockout
A02 on Ferroli Modena HE

Your boiler thinks it sees a flame even though it hasn't started the burner yet, which is a safety conflict that prevents it from running.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Flame detected with the burner off – electrode defective main board defective

What causes this fault?

This fault occurs when the boiler's internal sensor detects an electrical signal mimicking a flame before the heating cycle has actually started. This is usually caused by a carbon-coated or damaged electrode sending a 'false' signal, or moisture and debris on the burner assembly interfering with the detection system.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

A01View →A03View →

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