I think I would have the power company come out and check your incoming power. Have you had any instances where the lights either brown or brighten or where your microwave power doesn't seem just right? You may have a problem with your neutral and maybe getting more amps than you should. I had that happen and Consumers couldn't believe we didn't loose everything in the house that had motors, especially the refrigerator. It shouldn't cost anything and it's always better to be safe than experience a horrific house fire, especially when you have already survived one.