All 3 white control wires on 3 contactors to elements gets energized at the same time even when only calling for 2-3 degrees increase. Is that normal? I thought it was setup to increase elements based upon the amount of heat called for? The point is breakers keep tripping in winter for the last 2 years on and off. A 60 amp breaker on the unit tripping and is fryed, craked, and needs replacing. Also 100 amp main breaker on right side of main panel trips. Heating coils look good to eye and are not grounding out. I remove the bad breaker and one large coil from power until I can get a new one. The unit runs now but not sure if aux heat is engaging in proper sequence as it should and why breaker is tripping? Thank you.