BoilerFaultCodesYour boiler is displaying a service setting notification to run the pump at maximum speed, which usually indicates an installation or maintenance mode rather than a dangerous mechanical failure.
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 boiler has been manually adjusted to run its internal pump at maximum speed, typically during the initial setup or a system cleanse. It essentially means the energy-saving variable speed feature has been overridden to help flush air or debris out of the system. While not a mechanical breakdown, the boiler will stay in this high-performance mode until the setting is changed back to automatic.
DIY fix possible
Press the 'Mode' button to return the boiler to its normal operating screen.Turn the mains power to the boiler off and back on again to reset the display.If the code persists, check if the installer left the boiler in service mode.
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