Technical description
Incorrect fan speed
What causes this fault?
This fault occurs when the boiler's internal computer detects that the fan is not spinning at the required speed to safely clear exhaust gases. The most common reasons are a mechanical failure within the fan motor itself or a communication issue where the control board can no longer send signals to the fan. In some cases, loose or damaged internal wiring can also prevent the fan from receiving the power it needs 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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