High
80°C neon flashing on Potterton Performa 24

Your boiler is trying to start but failing to stay lit, which means it cannot provide hot water or heating until the issue is resolved.

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

Go to sections H and K - Spark at ignition electrode for up to 10 seconds / Burner lights / Burner extinguishes fault.

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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