BoilerFaultCodesYour boiler has detected an issue with its internal ventilation system, meaning it cannot safely clear waste gases and has shut down as a precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Air fault, pressure switch, no power to fan
What causes this fault?
This fault occurs when the boiler's internal safety sensors detect that the fan isn't moving enough air to safely vent exhaust gases outside. The most common reasons are a buildup of debris in the internal tubes, a mechanical failure of the fan itself, or a faulty sensor that can no longer confirm the system is safe to fire up.
This fault is more common during periods of high wind, as strong gusts can sometimes put back-pressure on the flue, interfering with the air pressure sensor's readings.
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 02 — no call-out fees, no surprises.
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