BoilerFaultCodesYour boiler's fan is not reaching the required speed, which means the system cannot safely clear exhaust gases and will not fire up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
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What causes this fault?
This fault occurs when the boiler's internal computer detects that the fan isn't spinning fast enough to safely push exhaust fumes out of the flue. The most common reasons are a buildup of debris inside the fan mechanism, a loose electrical connection, or a failing motor that can no longer maintain the correct speed.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 612 — 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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