High
Fault led (B) illuminated on Ideal Boxer

Your boiler is failing to ignite the flame it needs to heat your water or radiators due to a persistent ignition issue.

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

Boiler fails to light after 10 seconds

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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