BoilerFaultCodesYour boiler's fan is still spinning after the hot water has been turned off, preventing the system from restarting safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: DHW mode – fan overrun error
What causes this fault?
This fault occurs when the boiler’s software detects that the fan is still spinning at high speed after the demand for hot water has ended. The most common reason is a communication error between the fan and the control board, where the fan fails to slow down to a safe standby speed. It can also be caused by a sticking signal wire or a fault within the fan’s internal electronic motor.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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