BoilerFaultCodesYour boiler’s air fan is not spinning fast enough to safely clear out exhaust gases, so the system has shut down as a precaution.
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 internal fan isn't rotating at the required speed to safely expel waste gases. It is often caused by a buildup of debris within the fan assembly, a failing motor, or a fault in the electronic board that sends power to the fan.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like C1 — no call-out fees, no surprises.
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Worcester Bosch R30 35 And 40 HE Plus is discontinued — time for a new one?
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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