Air Conditioning - AC blower hangs

I have a Heil AC and gas heat system. The compressor is located outdoors and the remainder of the system is in the attic. The problem is that sometimes the blower continues to run after the compressor has stopped and the delay time has expired. The compressor will not restart and the blower will run forever. Cycling AC power to the controller board corrects the problem. I have replaced the furnace controller board and the thermostat. The problem still exists. Any suggestions are appreciated. This problem makes it hard to leave for an extended time without someone checking periodically to make sure it is running correctly.

Sounds like you may have another bad board or t-stat. What was wrong with the previous stat ?? Maybe you could put it back on to test the new one.

Changed the tstat on speculation. The old tstat kept track of system run time. When the compressor shut off and the blower stuck on the time would continue to accumulate. This didn't seem right if the tstat said shut off. The relays on the control board seem to be somewhat on the small side. Possibly the contacts temporarily weld? If so, it seems like any replacement board could act the same.