BoilerFaultCodesYour boiler's internal computer has encountered a software glitch or a communication error that is preventing it from running properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: PCB Software Error
What causes this fault?
This fault occurs when the boiler's main control board experiences a critical internal software error or fail-safe conflict. It is typically caused by a component failure on the PCB itself or a breakdown in communication between the board and the boiler's sensors. In some cases, a sudden power surge or electrical interference can corrupt the software instructions required to fire the burner.
DIY fix possible
Locate the reset button on the boiler control panel.Press and hold the reset button for 2 to 5 seconds.Wait for the boiler to complete its restart sequence to see if the error clears.
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A boiler cover plan would cover faults like L9 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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