My American standard comfort-r 95...well ive covered up ac unit for the season ..and thought to test furnace and get her ready for the cold weather I turn on the thermostat to high and well you hear it wants to start but then fails to ..I went to furnace and observed flashing red lights green flashing green light and so on I usaully just need to switch ac to heat up high my program times and dates all correct 23 all year round