High
Red LED flashing on Potterton Prima 30B

Your boiler has stopped working because it failed to light the burner after three attempts, so it has locked itself for safety.

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

Lockout - press reset. Possible ignition failure after 3 attempts

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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