High Lockout
0E2 on Alpha Pro Tec Plus

Your boiler is unable to confirm that the burner has successfully lit, so it has safely shut itself down to prevent gas buildup.

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 sensing fault.

What causes this fault?

This fault occurs when the boiler's control system cannot confirm that a flame has ignited after several attempts. The most common reason is a worn-out or dirty sensing probe that can no longer detect the heat, or a fault within the internal wiring that prevents the signal from reaching the main control board.

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.

Find a Gas Safe engineer
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Related fault codes

E02View →E04View →

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