BoilerFaultCodesTechnical description
The diagnostics will indicate the nature of the fault to assist a speedy and effective repair
What causes this fault?
This fault occurs when the boiler's internal computer detects that the fan is not spinning at the correct speed or has failed to start entirely. The most common reasons are a build-up of debris within the fan motor or a failure in the electrical signals sent between the control board and the air pressure sensor.
High winds during winter storms can occasionally cause back-pressure in the flue, which creates extra resistance for the fan and triggers this safety shutdown.
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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