Heating unit would not kick in. AC and fan unit work. When I looked at the main house breakers and I reset the heating unit it would not pop back on. It looked like it was not blown but when I reset it would not stay on. I turned the box off at the outside unit and it still would not reset. Would this probably be a breaker or short somewhere or a heating unit problem. This is an old house and we have not had any problems with the heating unit for 12 years. Any help appreciated.

Thanks,
Jon