High
Lockout on Ideal Concord CXA 40-120

Your boiler has stopped working because it failed to ignite the gas burner after five repeated attempts.

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

If, after 5 attempts the burner has failed to light, the boiler will go to lockout and [message] will be displayed on the screen.

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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