We had a Payne (high eff.) furnace installed in January 2002. On more than one occasion the furnace would not start up when heat was called for. We would trip the circuit breaker and flip it back on and the furnace would start up. I assume this resets something in the electronics. It will run properly for a while (hours, days, etc.) and then for no apparent reason not work when heat is called for. We would repeat the process of tripping the circuit breaker and it would work again. We had the service man who installed it out many times and he has yet to fix it. It is still under warranty and I am trying to get it fixed once and for all before the warranty runs out. Can someone tell me anything that I should have the service man look for? Could it be the thermostat? They are pretty much on/off switches and when the furnace is working it performs when the thermostat indicates a need for heat. We are getting pretty frustrated and beginning to question the service man's diagnostic abilities.