An induction box, or unit,provides a jet of air at the box, which entrains room air. The entrained room air mixes with the air from the jet of air from the induction box and mixes temperature. A small amount of air at high velocity from the induction box can cause a much larger quantity of air to flow in the direction of the induction box jet stream. The supply from the induction box might be 45 deg. F for instance and mixed with room air will create a flow of both induction box air and induced air to provide a comfortable mixed air temperature of 55 to 60 deg. F. air.
The induction box air, is usually comprised of mostly ventilaion, ie. outside air.
Steve