High
Lockout light on Ideal Concord CXA 40-120

Your boiler has failed to start up or stay burning, so it has purposefully turned itself off for safety and will not heat your home or water until fixed.

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 at the end of its ignition period. The controls will go to lockout almost immediately and the lockout light on the control panel will light.

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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