BoilerFaultCodesYour boiler's internal memory chip has developed a software or connection error, meaning it can no longer remember its correct settings to operate.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Parameter storage unit (PSU) error
What causes this fault?
This fault occurs when the boiler's internal memory chip fails to communicate with the main control board, similar to a corrupted file on a computer. It is usually caused by a hardware failure within the chip itself or a loose physical connection on the circuit board that prevents the boiler from reading its essential operating instructions. Because the boiler no longer knows its own safety limits or settings, it shuts down immediately as a precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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