I have the same exact problem with my Payne 90 Plus furnace. An HVAC repairman originally diagnosed it to be due to my new digital thermostat. He said the old mercury switch thermostats work better. After I found that the old mercury switch thermostat didn't work all the time either, I did some investigating on my own. I found that in my case the problem seems to be with the 3-pin molex connector that goes from the small motor you can see behind the front panel to the main circuit board. I watched it try to come on a couple of times and then pushed on the plug and VOILA, it started working normally. We used to cycle our fan off and on and it would start working again (similar to your resetting the circuit breaker). I think that process merely jarred the plug until it made good contact again. I haven't figured out how to fix the plug yet. I've tried cleaning it and pinching the connectors and it will work for a while and then goes on the blink again. I might succumb to replacing the circuit board, but Iím going to try fixing the plug again. Anyone else have some thoughts?