BoilerFaultCodesTechnical description
More than 5 start attempts without any flame formation.
What causes this fault?
This fault occurs when the boiler's control system attempts to ignite the burner five times but fail to detect a stable flame. The problem is usually caused by a lack of gas supply, a worn-out ignition spark electrode, or a blockage in the flue system preventing the gas from burning safely.
This fault is more common during extreme cold snaps, as external gas meters or regulators can freeze, restricting the gas flow required for ignition.
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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