The Drives that are vvvf16L, are not the most durable Drives by any means. However when they go bad the Elevator shuts down completely and does not run until the Drive is changed out. The newer Drives are indeed more robust.It seems like you have a problem unrelated to the Drive. Kone is a well known and reliable Elevator Company. If they are maintaining your unit, and you are not getting the co-operation, and satisfaction you need to address your problem, call the Factory in Moline ILL. and have the operator put you through to a manager. He will get the attention of the Branch Manager in Indiana fairly quickly.