High
E43 on Alpha Evoke

Your boiler has tried to light the flame several times but has failed, so it has safely shut itself down to prevent wasting gas.

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

Loss of flame signal (more than 6 times)

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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