Hi. I have split unit. With the Air handler / Furnace in the Attic. There are three Fuses. One by the condenser outside unit, one at the main CB, and one in the attic next to the Furnace. Two days ago the heater melted the attic service breaker, so the CB Box got replaced thinking it was a faulty box. Today it tripped the CB again. The fan and heat will run for a day or so, then it acts as if it is overdrawing Amps. I replaced the capacitor thinking it was the motor having a hard start. Could it be that the motor is just over drawing amps after it runs for while and gets hot?

The best way to find your problem is with a Amprobe. This way you can take current draw measurements and check them against the furnace/air handler manufacture plate. All power needs will be addressed on that plate and when you take a reading you just compar. Anything electrical that is using more current than on the manufacture plate should suspect of causing the problem.