High
Lockout on Potterton Combi 80

Your boiler has stopped working for safety reasons because it failed to light or became too hot, so it has purposefully shut itself off to protect your home.

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

Loss of gas supply, flame failure, or over-heating of the central heating water will cause the appliance to shut down or Lockout. This will be indicated by the lockout light being illuminated.

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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