Temp in my home will not drop below 81 deg...

Air Handlers differ in the way they adjust there variable speeds. Carrier you just plug into a pin. Trane has dip switches with directions on the fan housing. Before you try to adjust please kill power to air handler. Varriable speed are very sensative to voltage. If I new your air handler brand I could help. But just check the wiring diagram and they may ahve dirrections on there for setting speed. Need more help call back Rus