BoilerFaultCodesTechnical description
More than 5 start attempts without any flame formation.
What causes this fault?
This fault occurs when the boiler is unable to detect a stable flame after several attempts to ignite the gas. The most common reasons include a blocked gas supply, worn-out spark electrodes failing to create a spark, or a dirty sensor that cannot tell the boiler the flame is actually lit.
This fault is more common in winter, as extremely cold temperatures can cause external gas regulators or condensate pipes to freeze, preventing the boiler from firing safely.
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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