The fan needs replacing, it is seizing due to the deterioration of grease in the bearings. The fan stopped will cause the boiler to trip on no air flow, there must be air flowing in the flue to allow the boiler to start up. Probable cost £120 to be replaced.
Don
October 2010
I can answer this question...
worcester 350,why does fan stop and boiler turn off after a min ?
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