BoilerFaultCodesTechnical description
Failure to ignite
What causes this fault?
This fault occurs when the boiler's control system fails to detect a steady flame after several attempts to start. It is usually caused by a worn ignition spark that cannot light the gas, or a dirty sensor that fails to tell the boiler the flame is actually lit. In some cases, the gas valve may be stuck or electrical components have failed, preventing the combustion process from beginning.
This fault can appear more frequently during the first cold snap of autumn when internal components that have been idle all summer struggle to move or ignite correctly.
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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