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.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Ideal Boiler Boxer C24 And 28 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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