BoilerFaultCodesWhat the manual says
Manufacturer manualFan speed too low.
What causes this fault?
This fault occurs when the boiler's control system detects that the fan is not spinning at the correct speed to safely expel waste gases through the flue. The most common reasons include a buildup of dust and debris within the fan motor, a loose electrical connection, or a failing control board that is unable to send the correct power signal to the fan.
This fault is slightly more common in winter when the boiler works harder and the fan runs for longer periods, which can cause aging motor bearings to seize or fail.
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.
Avoid the next call-out bill
A cover plan would handle faults like C1: no call-out fees, no surprise bills.
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