High
Safety Lockout LED (Red) on Halstead Ace High

Your boiler has stopped working because it failed to start the burner, meaning you currently have no heating or hot water.

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

Burner has failed to light and gone to ignition lock-out and possibly overheat cut-out.

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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