BoilerFaultCodesWhat the manual says
Manufacturer manualfan error (start-up)
What causes this fault?
This fault occurs when the boiler's internal computer detects that the fan is spinning at an incorrect speed or the air flow isn't being measured correctly. The most common reason is a small blockage or moisture buildup in the thin silicone tubes that monitor pressure, or the fan itself may be starting to wear out and struggle to reach the required speed.
This issue can be more frequent during periods of high wind or extreme cold, as external air pressure changes or frozen debris in the flue can interfere with the fan's air flow sensors.
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 34: no call-out fees, no surprise bills.
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