BoilerFaultCodesYour boiler is failing to start up because the internal fan, which clears waste gases, is not spinning.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The fan does not start. Check the power from the room thermostat, interface board or control board (PCB), or fan (loose terminal connector, windings burnt out).
What causes this fault?
This fault occurs when the boiler's safety system detects that the fan isn't spinning to clear away combustion gases, preventing the ignition process from starting. The most common reason is that the fan motor has seized or the electrical components on the main control board have failed and aren't sending power to the fan. In some cases, it can simply be caused by a loose wire or a build-up of debris inside the fan housing blocking movement.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like Warning light flash (after 45 seconds) — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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