BoilerFaultCodesYour boiler's internal computer has lost track of the time or date, which can prevent your heating schedules from working correctly.
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: Internal clock time error on printed circuit board (PCB)
What causes this fault?
This fault occurs when the boiler's internal computer has lost its programmed date and time settings, often following a power cut or if the boiler has been switched off at the mains for a long period. In some cases, it can also suggest that the internal battery or memory chip on the printed circuit board is starting to fail and can no longer store information.
DIY fix possible
Locate the control panel on the front of the boilerEnter the settings menu to find the 'Time and Date' optionsUpdate the clock to the current time and save the settings
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A boiler cover plan would cover faults like E100 — no call-out fees, no surprises.
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