BoilerFaultCodesTechnical description
Failure during start-up: Ignition unsuccessful
What causes this fault?
This fault occurs when the boiler attempts to ignite but cannot confirm that a steady flame has been established. The most common reasons include a lack of gas reaching the burner, a worn-out ignition spark, or a buildup of carbon on the sensor that detects the heat.
This fault is more frequent during extreme cold snaps, as the external gas regulator can freeze or the condensate pipe can become blocked with ice, preventing the boiler from firing.
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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