Sounds like a poor connection between the furnace and the control
Tim nothing has changed relative wiring ... i noticed outside at the a/c compressor unit the wiring looked disturbed .. but could not rationalize a problem with the thermostat ... outside of resistance check what would u recommend
I would check all the connections on both ends. Wiring is funny, it can look OK, but you go to touch it or move it and you find a broken off or loose connection.
ok if i come up empty can I by a standard digital thermostat to replace the evolution even though I have the integral humidity and variable speed motor or am is stuck in an evolution?
It's meant to go with the board on that furnace. Yes, you're stuck with it.
One thing you can try is to totally cut the power to your furnace for 20-30 min. Then turn back on and let the control reset itself.