BoilerFaultCodesTechnical description
Fault on Fan or Flue
What causes this fault?
This fault occurs when the boiler's internal safety system detects that the fan isn't spinning at the right speed or the exhaust gases aren't being pushed out of the flue correctly. The most common reason is that the fan motor has worn out or a small internal tube has become blocked with debris, preventing the boiler from starting its ignition sequence safely.
This fault can be more common during periods of high winds, as strong gusts can occasionally create back-pressure in the flue that interferes with the air pressure sensor.
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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