BoilerFaultCodesYour boiler is not broken; it is simply in 'Installer Mode' which is used during setup or testing and can be exited by adjusting the control knobs.
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: Installer Mode setting code
What causes this fault?
This occurs because the control knobs on the front of the boiler have been placed into a specific sequence used by engineers to test the system's performance. It is usually triggered accidentally during cleaning or when someone is trying to adjust the temperature settings manually. Because the boiler is waiting for programmed instructions from an installer, it pauses normal heating operation until the mode is deactivated.
DIY fix possible
Turn the DHW (Hot Water) thermostat knob fully clockwise then fully anticlockwise.Turn the CH (Heating) thermostat knob fully clockwise then fully anticlockwise.The display should return to the standard temperature reading.
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