BoilerFaultCodesYour boiler's main internal computer has lost its settings or has developed an internal electrical fault, preventing it from starting.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: PCB UNCONFIGURED OR FAULTY
What causes this fault?
This fault occurs when the boiler's main control board loses the essential software instructions needed to operate the system safely. The most common reason is a memory failure within the data chip or an electrical surge that has corrupted the board's internal settings, meaning the boiler no longer knows which model it is or how to fire correctly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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