I have a new Bryant evolution HVAC system installed which is tied to a Bryant evolution thermostat. The installer suggested that the fan setting be left on Low. His rationale was that the fan running on low at all times would add to the circulation and comfort in the home. He mentioned that since the blower is an infinte speed blower it would adjust as needed when the heat or AC came on, so not always running on low. He said they recommend the upstairs level (second floor) system to be on Auto and the main level on Low. Said that running the fan all year on low is like $40 per year so not significant.
Does this make sense?