BoilerFaultCodesYour boiler is staying in a cooling-down mode because it thinks the air fan is still spinning when it should have stopped.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: fan overrun
What causes this fault?
This fault occurs when the boiler's control board detects that the fan is still rotating even though the power to it has been cut. The most common reason is a communication error between the fan and the main circuit board, often caused by a failing fan motor or moisture affecting the sensitive electronic sensors.
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 S.16 — no call-out fees, no surprises.
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