High
ON OFF ON on Baxi Solo

Your boiler has tried to start up several times but failed to light the flame, causing it to shut down for safety.

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

Ignition lockout error

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's control system attempts to light the burner multiple times but fails to detect a stable flame. The most common reasons include a worn-out ignition spark, a faulty gas valve that isn't opening properly, or an issue with the sensor that confirms the fire is actually lit.

This issue is slightly more frequent in winter as cold weather can affect gas pressure and put older, struggling ignition components under more strain.

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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