High
neon flashing (Section H/K) on Potterton Performa 24 Eco HE

Your boiler is trying to start but failing to light the flame, so it has safely shut down to prevent a 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

Ignition fault - Spark at ignition electrode for up to 10 seconds but burner does not light

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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