BoilerFaultCodesTechnical 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 clear exhaust gases from the system. The most common reasons are a mechanical failure of the fan motor, a blockage in the flue pipe, or a split in the small rubber tubes that monitor air pressure.
This fault can occasionally occur during periods of high winds, as strong gusts blowing directly into the flue terminal can temporarily disrupt the airflow required for the boiler to start.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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