Abstract: A non-volatile storage system includes non-volatile storage elements and one or more managing circuits in communication with the non-volatile storage elements. The non-volatile storage elements are arranged in blocks including a first block reserved for system use and a second block. The first block stores a pre-determined data pattern that was written to the first block subsequent to system testing and prior to completion of manufacturing of the non-volatile storage system. Subsequent to completion of manufacturing of the non-volatile storage system, the one or more managing circuits sense information stored in the first block and determine an error metric for the sensed information with respect to the pre-determined data pattern. The one or more managing circuits determine that the system experienced an IR reflow process if the error metric was determined to satisfy the threshold.