BoilerFaultCodesYour boiler is currently in a manual testing mode where it runs at its lowest power level, often used by engineers during a service.
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: Boiler is operating at minimum output (Test program 'L')
What causes this fault?
This code appears because the boiler has been manually put into a specific testing mode, usually by an engineer during a service or repair. It occurs when a specific button combination is pressed on the control panel, telling the boiler to stay at its lowest heat output. It is not a mechanical failure but rather a status indicator that the 'low power' test program is active.
DIY fix possible
Press the '+' and '-' buttons simultaneously to exit the test modeIf the display does not change, press the 'Reset' button brieflyTurn the boiler off at the fused spur switch for 30 seconds and turn it back on
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