[Jeepshots]

Chuckster's right, but what isn't readily clear is that the thermostat has three modes, other than off. First mode is fan speed - high, low or auto (he explained that). Second mode is Air Conditioner - set the temp you want it to come on. Third mode is Heat - set the temp you want the furnace to come on. Which ever mode you have active is what the system will run with. The Fan mode is the one that will keep it's setting and run in the background of the other modes. So if you want the fan running all the time, set it to high or low, then flip over to which ever system you want - A/C or heat. Or, just leave it on the Fan mode. Does that make sense?