Should the outside Grand Aire compressor/fan be on while central heat is being used? The thermostat is at 68 degrees and have not heard or seen the compressor working; am concerned because heat kicks on every half hour to keep it at 68 degrees. In Florida and not used to these unusually cold temps (house is not sealed very well, so that may be why heat kicks on every half hour). Thanks!

It will work only if you have a heat pump. If you have a heat pump and it is not working then check the circuit breakers. If that fails you will need to call for on site service.