Hello all I have 2 little 5 ton splitters both bought used. Both are stored in the shed I brought them to the garage today because one needed a new motor and the other change the oil. I plugged one in and it wouldn't run it just hummed and tripped the breaker. After a few minutes it worked great. The other I installed a new motor and control box and it did the same thing. I don't understand why it was all new.