Hey trane , Why does it matter why the other pack burned up ? It was out of warranty and it was money better spent to buy a new one . The hvac guy that looked at it said ( two companys looked at it ) They both said they didnt know why it caught fire and suggested he buy a new one . I told him to go price a new one and do it himself . he went into a local supply house and bought one . ( Good advise ) I thought , since i been on here for several years that I might find a contractor to check it out ! its Too bad for the site that a few angry contractors get on here and blast people for asking for help . BH