Upon my arrival I found that the comfort control had came back and that the system was flashing error code 13. This error code is a high temperature lock out. The system was trying to heat to 74 and the attic it is in is at 94 degrees already. I believe the system got to hot and tripped the sensor. I checked all functions and found it all to be operating properly. Check the exhaust vent pipe and it was clear of any restricts and the coil had a good split. Told the customer is this happens again to call back and we will schedule him for Monday.