BoilerFaultCodesYour boiler is flagging a minor technical adjustment error regarding its internal fan speed settings.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Offset for maximum speed
What causes this fault?
This fault occurs when the boiler's control board detects that the internal fan is operating at a speed that doesn't match the expected safety settings. It is usually caused by an electronic communication error between the main circuit board and the fan, or a slight decalibration in how the gas valve is being controlled. While the boiler may still operate, it signifies that the internal components are not perfectly synced.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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