BoilerFaultCodesTechnical description
No ionisation detected after ignition
What causes this fault?
This fault occurs when the boiler's internal sensor fails to detect a flame, even though it may have tried to spark and light several times. The most common reason is that the gas is not reaching the burner properly or the sensor responsible for 'seeing' the flame has become dirty or worn out.
This fault is more common in winter, as extremely cold temperatures can cause external gas meters or condensate pipes to freeze, preventing the boiler from lighting.
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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