It appears that the furnace is not working. I have the thermostat set on 80 but the unit does not come on. It's 30 degrees out. I played around with the thermostat some and it come on once but blew cool air. A previous furnace had a red reset button that I needed to occasionally push. I think this happened when the wind came from the direction of my wall vent. Is there a reset button on this unit?