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 spinning fast enough or the exhaust pipe is blocked. Because the boiler cannot safely expel harmful waste gases, it will automatically shut down to prevent them from entering your home. Common causes include a seized fan motor, a buildup of dirt in the air tubes, or a physical obstruction in the flue pipe outside.
This fault can be more common during periods of high winds, which can create back-pressure in the flue and interfere with the air pressure sensor's readings.
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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