BoilerFaultCodesYour boiler is notifying you of a minor technical calibration adjustment regarding the fan's lowest operating speed.
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 minimum speed
What causes this fault?
This code appears when the boiler's control board detects that the fan is spinning at a slightly different speed than expected during its lowest setting. It is usually caused by natural wear and tear of the fan motor or small electrical inconsistencies between the fan and the main circuit board. While the boiler is correcting itself, it indicates that these components are no longer perfectly synchronised.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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