High
Neon flashing (Generic) on Potterton Performa 24

Your boiler has detected an internal error and has temporarily stopped working to prevent damage, often caused by low system pressure or a temporary glitch.

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

Flashing indicates a fault condition requiring reset or investigation in the primary/DHW/CH operational sequences.

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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