BoilerFaultCodesYour boiler’s control panel has become locked or entered a restricted mode, preventing you from changing any settings or operations.
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: Control panel locked.
What causes this fault?
This issue occurs when the boiler's internal software triggers a security lock on the control buttons, often due to a specific sequence of accidental presses or a glitch in the programming. In some cases, it can be caused by a communication error between the main circuit board and the display panel, effectively freezing the interface. Usually, it is a safety feature intended to prevent settings from being tampered with rather than a mechanical failure.
DIY fix possible
Locate the 'Mode' or 'Reset' knob on the front panel.Turn the dial to the 'Reset' position and hold it there for approximately 5 seconds.Return the dial to your desired setting (either Heating and Hot Water or Hot Water only) to see if the display clears.
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