Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.
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: Text display not yet defined
What causes this fault?
These codes appear when the boiler's internal computer is running through its initial boot-up sequence or performing a temporary software update. They are typically seen after the power has been switched off and back on, or following a brief interruption in the electrical supply. It is the system's way of checking all safety sensors and settings before it begins the ignition process.
This code may be seen more frequently during winter months if local power outages or grid fluctuations occur due to heavy storms.
DIY fix possible
Wait for up to 15 minutes to see if the code clears automatically as the system boots up.If the code persists, try restarting the boiler by turning the power off and back on at the fused spur switch.Check if the reset button is illuminated and press it once if the display remains stuck.
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