BoilerFaultCodesYour boiler is currently in a manual service mode used for testing and is not experiencing an actual fault.
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 run the burner at minimum rate
What causes this fault?
This code appears because the boiler has been manually put into a specific testing mode by a person pressing buttons on the control panel. It is triggered when the service functions are activated to hold the burner at its lowest internal setting, typically so an engineer can take precise combustion readings. Because it is a manual setting rather than a mechanical failure, it simply means the boiler is following a specific command rather than encountering a problem.
DIY fix possible
Turn the mode selector knob away from the 'Service' or 'Test' positionSwitch the boiler off at the fused spur switch for 30 secondsSwitch the power back on to return the boiler to normal operation
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