I have a goodman heat pump (3 years old). The thermostat is set at 72 and it is 43 degrees outside. I realized it was chilly in the house, I then reset the thermostat to 74. The heat pump came on and it is two hours later, the house is resting at 74 but the heat pump is still on and it is blowing out cool air. I lowered the thermostat to 73 and the unit cut off, only to come back on 5 minutes later and is still running. The unit was serviced (low freon) and cleaned 7 weeks prior, all the filters have been changed. At this point the unit is running up my electric bill and not keeping us warm. What's wrong with this unit?