BoilerFaultCodesYour boiler's fan is not spinning fast enough to clear out exhaust gases, which is preventing the burner from starting up safely.
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 too low at burner start
What causes this fault?
This fault occurs when the boiler's control system detects that the fan isn't reaching the necessary speed to safely clear waste gases before ignition. The most common reasons are a build-up of debris causing mechanical resistance within the fan itself, a loose electrical connection, or a communication failure from the main control board.
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 F9 — no call-out fees, no surprises.
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