BoilerFaultCodesYour boiler's internal memory chip has developed a communication fault, meaning the control board can no longer read its essential settings.
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 small plug-in memory chip on the main control board fails or loses its connection. It is usually caused by an electrical glitch or internal wear and tear that prevents the boiler from identifying its own model and safety settings. Without these specific instructions, the boiler shuts down immediately as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 5 red flashes — 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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