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.

What the manual says

Manufacturer manual

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.

From this model's manual
Verified against the Potterton Combi 80 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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