BoilerFaultCodesYour boiler has stopped working because the internal fan isn't spinning fast enough to safely clear away exhaust fumes.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan 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 required speed to safely eject waste gases through the flue. The most common reason is mechanical wear within the fan motor itself, though a buildup of debris or a failing control board can also prevent the fan from reaching full power.
This fault is slightly more common in winter when the boiler is working harder, as the increased demand can cause an aging fan motor to finally seize or fail.
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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A boiler cover plan would cover faults like C1 — 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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