BoilerFaultCodesTechnical description
Check gas supply, check flue system, check polarity
What causes this fault?
This fault occurs when the boiler's control system attempts to start a flame but fails to detect one after several attempts. It is physically caused by either a lack of fuel reaching the burner, a failure of the spark to ignite the gas, or a sensor that cannot 'see' the flame even if it is lit.
This fault is more common during the first cold snap of autumn when gas valves can stick after being idle all summer or when air locks have formed in the gas line.
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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