My refrigerator is tripping a 15A circuit. The line is dedicated to the refrigerator and when I move the refrigerator to another circuit it trips that one. Tripping doesn't happen right away. Maybe after 24-48 hours. Can someone help me understand what the problem might be, what's required to fix and how much a general repair might cost? Note this is and older refrigerator, I'm not sure of it's age.