BoilerFaultCodesYour boiler is displaying a service setting notification rather than a breakdown, indicating the internal pump is being told to run at its maximum 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: To set the minimum CH pump speed to 100%
What causes this fault?
This code appears when the installer or a service engineer has manually activated a specific setting within the boiler's menu. It physically forces the internal pump to run at full power constantly for testing or to clear air from the radiators. It is not a hardware failure, but rather a configuration mode that has been left switched on.
DIY fix possible
Press the 'Mode' or 'Reset' button to exit the installer function menuSwitch the boiler off and back on at the main fused spur switchMonitor the display to see if the code clears and returns to the temperature display
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