BoilerFaultCodesYour boiler has detected that it was turned on while its internal computer chip was being replaced or updated.
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 powered on during PCB replacement
What causes this fault?
This fault occurs when the boiler's main control board is powered on while the firmware chip is being handled or the system is in an incomplete update state. It typically happens if the electricity is turned back on before a technician has fully finished swapping out the internal computer components. It essentially means the boiler’s brain wasn't ready to start up when the power hit it.
DIY fix possible
Locate the main power switch for the boiler (usually a fused spur switch nearby).Turn the power off completely.Wait for 30 seconds.Turn the power back on and the code should disappear.
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