Im sure you guys have converted it, but what would you suspect would cause random trips in a gfi circuit? I went to a call the other day, customer had a gfi tripping, he replaced the gfi, but it was still tripping. I checked termination on gfi, it was good, then found a Christmas light plug with the plug facing up to collect the rainwater. So I blew the plug out, turned the plug upside down and stayed 20mins, no trip. Well customer called yesterday said it tripped again. I'm kinda stumped.