BoilerFaultCodesYour boiler is signalling a setup issue related to the fan's speed range, meaning it is not operating at its intended maximum performance level.
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 unable to reach its specified maximum speed setting. It is usually caused by a communication error between the main circuit board and the fan, or an incorrect configuration value stored in the boiler's memory. This means the appliance cannot safely ramp up to its full heating power, though it may still operate at a lower capacity.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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