BoilerFaultCodesTechnical description
No or insufficient ionisation flow
What causes this fault?
This fault occurs when the boiler's internal sensor fails to confirm that a flame has successfully ignited. The most common reasons include a worn-out ignition spark, a blockage in the gas supply, or a dirty sensor that can no longer 'see' the heat produced by the burner.
This issue often surfaces during the first cold snap of autumn when the boiler is forced to work harder after sitting idle through the summer months.
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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