BoilerFaultCodesTechnical description
Ionisation failure
What causes this fault?
This fault occurs when the boiler's internal computer cannot confirm that a flame has successfully lit inside the combustion chamber. The most common reasons are a worn-out sensor that can no longer 'see' the flame, a buildup of carbon on the electrodes, or a lack of gas reaching the burner.
This issue is slightly more frequent during the first cold snap of winter, as gas valves can occasionally stick after being inactive throughout 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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