BoilerFaultCodesTechnical description
No flame detected or flame signal loss during operation
What causes this fault?
This fault occurs when the boiler's internal computer tries to light the gas burner but cannot confirm that a steady flame is present. The most common reasons are a blocked or dirty ignition probe, or a problem with the gas supply preventing the burner from catching light correctly.
This fault is more common in winter, as frozen condensate pipes can cause a backup of water that prevents 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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