I have a standard forced air furnace and no air conditioning. I also have a wood stove. I was told I could run the blower on the furnace without the heat in order to circulate the air in the house. How do I program the thermostat to just run the fan? I have tried just about every setting possible (I think) and nothing happens. Everything works fine when I am using the furnace to heat, but not when I am trying to just move the air through the system. Can this be done?