High
RED lockout led on Ideal Boxer

Your boiler has failed to start up or stay burning, so it has safely turned itself off to prevent a build-up of unburnt gas.

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

The boiler does not light after 10 seconds. Press the reset button and the boiler will repeat its ignition sequence.

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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