BoilerFaultCodesTechnical description
fan overrun
What causes this fault?
This status occurs when the boiler's fan continues to run for an extended period after the burner has finished heating your home or water. It is usually caused by the main circuit board failing to tell the fan to stop, or the fan itself sending an incorrect signal back to the control system. While it often resolves itself, it can sometimes suggest the electronic components are beginning to wear out.
DIY fix possible
Check if the boiler is currently in an anti-cycle or overrun modeWait up to 10 minutes to see if the fan shuts off automaticallyIf the fan continues indefinitely, try a system resetMonitor the boiler for any subsequent fault codes (e.g., F.xx)
Find a Gas Safe engineer
Search the official register →