BoilerFaultCodesYour boiler's fan is staying on for too long or running when it should be finished, preventing the next heating cycle from starting safely.
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 system detects that the fan is still spinning even after it was told to stop. The most common reason is a communication error between the main circuit board and the fan, or a physical fault within the fan motor itself that prevents it from shutting down correctly. Because the fan is a safety-critical component, the boiler pauses operation to prevent an unsafe mixture of gas and air.
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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