BoilerFaultCodesYour boiler is currently stuck in a checking stage where the fan is running but the burner has not yet lit.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: fan pre-run
What causes this fault?
This fault occurs when the boiler's control system is waiting for confirmation that the fan is spinning at the correct speed to safely clear out gases before ignition. The most common reason is that the fan has become worn or blocked, or the circuit board is failing to receive the electrical signal required to move to the next step of the starting process.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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