BoilerFaultCodesTechnical description
No flame signal following starting procedure
What causes this fault?
This fault occurs when the boiler's control system fails to detect a flame after several attempts to ignite the gas. It is usually caused by a lack of spark, a blocked gas supply, or a dirty sensor that cannot 'see' the flame even if it has successfully lit. Over time, soot buildup or wear on the internal ignition parts prevents the boiler from firing up safely.
This fault is more frequent during the first cold snap of winter when the gas valve may stick after sitting idle or when extreme cold affects the external gas supply pressure.
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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