BoilerFaultCodesTechnical description
Flow Sensor Fault - Problem with the central heating flow temperature sensor
What causes this fault?
This fault occurs when the boiler's internal computer detects that the fan is either spinning too slowly or not moving at all. The most common reason is a mechanical failure within the fan motor or a communication error on the main circuit board that prevents it from sending power to the fan. Without a functioning fan, the boiler cannot safely expel waste gases, so it shuts down as a safety precaution.
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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