BoilerFaultCodesWhat the manual says
Manufacturer manualfan overrun
From this model's manual
Verified against the Glow Worm Ultracom 2 Cxi installation & service manual, page 52.
What causes this fault?
This fault occurs when the boiler's internal computer detects that the fan is spinning for too long or at an unexpected time during the ignition sequence. The most common reason is a communication error between the fan and the main control board, or the fan itself beginning to wear out and failing to stop when instructed.
DIY fix possible
Monitor the boiler to see if it clears the status and starts successfullyPerform a simple reset by pressing the reset buttonEnsure there are no external blockages to the flue terminal
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