High
Lockout light on Potterton Puma 100e

Your boiler has stopped working because it cannot light its burner or has detected an internal safety problem and shut itself down to prevent damage or risks.

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

Indicated by the lockout light being illuminated. Caused by loss of gas supply, flame failure, or over-heating of the central heating water.

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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