BoilerFaultCodesYour boiler is staying in a cooling-down phase for too long because it thinks the fan is still spinning after 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: Heating mode – fan overrun error
What causes this fault?
This fault occurs when the boiler's control board expects the fan to stop spinning after a heating cycle, but it continues to receive a signal that the fan is still rotating. The most common reason is a communication error between the fan and the main circuit board, often caused by a faulty sensor inside the fan or a sticking internal component. In some cases, a damaged wiring harness or moisture on the electronics can prevent the fan from shutting down correctly.
DIY fix possible
Press the reset button (indicated by a flame with a cross through it)Turn the boiler power off at the fused spur switch, wait 30 seconds, and turn it back onCheck for any visible obstructions or debris around the external flue pipe terminal
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A boiler cover plan would cover faults like S.06 — no call-out fees, no surprises.
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