BoilerFaultCodesYour boiler has detected an issue with the internal fan, which is preventing the system from safely clearing exhaust gases and starting up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan speed fault
What causes this fault?
This fault occurs when the boiler's control system loses the ability to manage or monitor the speed of the internal fan. The most common reason is a mechanical failure within the fan motor or a communication error on the circuit board, meaning the boiler cannot safely expel exhaust gases. As a result, the system shuts down as a vital safety precaution to prevent dangerous fumes from building up.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 0A5 — 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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