Your system only exchanges heat with the outside (via a refrigerant). The fan only circulates air; on its own, it doesn't draw air from the outside (by design;

Your system only exchanges heat with the outside (via a refrigerant). The fan only circulates air; on its own, it doesn't draw air from the outside (by design; you don't want to be cooling outside air). The system would need to have a second mode and a fresh air intake, as well as wiring and support from your thermostat. It can be done, but HVAC is a slow-moving industry.