BoilerFaultCodesTechnical description
No ionisation detected after ignition
What causes this fault?
This fault occurs when the boiler's internal computer tries to start the burner multiple times but cannot confirm that a steady flame has been established. The most common reasons include a lack of gas supply to the unit, a blocked pipe that removes waste water, or dirty internal sensors that can no longer 'see' the flame effectively.
This fault is frequently seen during freezing winter temperatures, as the external condensate pipe can freeze solid, causing water to back up into the boiler and prevent it 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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