High
Detection lockout on Ideal Concord Cxdi

Your boiler has stopped working because it cannot light the internal flame or detect that it is burning correctly.

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 flame failure safety device has activated, likely due to no gas or a failure to detect the flame.

From this model's manual
Verified against the Ideal Concord Cxdi 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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