Non specific to BK, but break in fires usually refer to temps more than a setting. Each MFG and manual could have their own specifics, but in general a 3 fire break in does about anything you would need to do. First fire - low temps (say 200-250F ish). Let cool. Second fire - mid temps (somewhere in the world of 400F). Third and final - let it rock and roll while making sure to not overfire.
ETA - any specifics from the manual trump the above info.
ETA - any specifics from the manual trump the above info.