BoilerFaultCodesTechnical description
No flame seen through spy glass, no spark across electrodes, or flame sensor/wiring fault.
What causes this fault?
This fault occurs when the boiler attempts to ignite but fails to detect a steady flame after several tries. The most common reasons are worn-out ignition sparks that can no longer light the gas or a layer of carbon buildup on the sensor that prevents the boiler from 'seeing' the flame even if it is actually lit.
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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