Technical description
Fan fault
What causes this fault?
This fault occurs when the boiler's safety system detects that the fan is not spinning fast enough to safely clear waste gases from the flue. The most common reasons are a buildup of dirt on the fan blades, a failure in the fan's motor, or a communication issue where the main control board can no longer control the fan speed.
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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