My airtron furnace comes on and runs for fine for a couple of days and then it will come on then shut off come on and then shut off(the blower)(or fan) and then after awhile it runs fine,it seems to only do this at night for some reason during the day it seems to run fine,I keep it at 75 during the winter and the air is on and off during the summer so I'm not running it constantly but but up till feb of this year it has ran fine now it doesn't twanna run right any suggestion,it has a digital thermostat,it seems I have to reset it over and over again at night to keep it on