BoilerFaultCodesYour boiler is unable to safely clear exhaust fumes from the system, so it has shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault on Fan or Flue
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 expel exhaust gases through the flue. The most common reasons are a seized fan motor, a blocked flue pipe, or a build-up of dirt in the small tubes that measure air pressure. Because the boiler cannot guarantee that harmful fumes are being cleared, it shuts down immediately to prevent them from entering your home.
This issue can sometimes be triggered during periods of high winds, as strong gusts can cause pressure fluctuations in the flue that interfere with the air pressure switch.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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