BoilerFaultCodesTechnical description
Flashes to indicate ignition operation (stops after detection).
What causes this fault?
This indicator appears when the boiler's control system is sending an electrical charge to the spark electrode to ignite the gas. It occurs during the normal start-up sequence, but if it persists without the boiler firing, it usually means the fuel is not igniting or the system cannot 'see' the flame. The most common reasons for a failure at this stage are a worn-out ignition lead, a carbon-coated electrode, or a fault with the burner itself.
DIY fix possible
Check that your gas supply is turned on at the meterIf the light continues to flash without the boiler firing up, press the reset buttonEnsure any external controls like thermostats are calling for heat
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