BoilerFaultCodesYour boiler is currently running a self-diagnostic test or is in a temporary programming mode indicated by a yellow flashing light.
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: Led analysis test (blink yellow)
What causes this fault?
This code appears when the boiler’s control dial is moved into a specific position, triggering a self-test or setup mode. It usually happens if the dial has been accidentally moved past its normal settings or if the control knob is loose, causing the internal switch to sit between two functions. It is a temporary status rather than a mechanical failure of the internal components.
DIY fix possible
Wait 10-15 minutes for the light to stop flashing automaticallyEnsure the mode selector dial is set to 'Hot Water' or 'Heating and Hot Water' rather than the 'Reset' positionRotate the selector dial to 'Reset' for 5 seconds and then back to your desired setting
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