Your boiler is currently updating its internal settings and is showing this code to indicate it has been reset during its configuration process.
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: Display status after pressing RESTART during PCB programming
What causes this fault?
This code appears because the boiler's internal computer has just been reset or is going through a setup process. It physically signifies that the circuit board is checking its own software settings to ensure everything is configured correctly for your home. While it looks like a fault code, it is actually just a brief status update showing that the system is rebooting.
DIY fix possible
Wait 5-10 minutes for the boiler to complete its internal programming sequence.If the code persists, ensure the boiler is not being manually reset repeatedly.If the display does not return to the normal temperature reading, turn the power off and back on at the fused spur switch.
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