A friend just built his house a couple of years ago. He noticed that he wasn’t getting much heat from his furnace. So he called another friend that did his HVAC work and asked that he come out and diagnose the problem. He found out that the air handler wasn’t getting enough power for the heat strip. He traced it back to the panel. After opening the panel they could see that the breakers were melting. He removed a few breakers and the aluminum bus bar was covered in plastic. So the homeowner called the electrician (another friend). He came out and called the supply company, who put him in touch with a cutler-hammer representative. The representative acknowledged that they were aware of the problem and that they would send out a replacement panel.
So pay close attention to any cutler-hammer panels you come across that are less than 5 years old.